How-To Tutorials

  Microsoft SQL Azure Enterprise Application Development Build enterprise-ready applications and projects with SQL Azure Develop large scale enterprise applications using Microsoft SQL Azure Understand how to use the various third party programs such as DB Artisan, RedGate, ToadSoft etc developed for SQL Azure Master the exhaustive Data migration and Data Synchronization aspects of SQL Azure. Includes SQL Azure projects in incubation and more recent developments including all 2010 updates Appendix         Read more about this book       (For more resources on Microsoft Azure, see here.) SQL Azure is a subset of SQL Server 2008 R2 and, as such, the tools that are used with SQL Server can also be used with SQL Azure, albeit with only some of the features supported. The Microsoft tools can also be divided further between those that are accessed from the Visual Studio series of products and those that are not. However, it appears that with Visual Studio 2010, the SSMS may be largely redundant for most commonly used tasks. Visual Studio related From the very beginning, Visual Studio supported developing data-centric applications working together with the existing version of SQL Server, as well as MS Access databases, and databases from third parties. The various client APIs such as ODBC, OLEDB, and ADO.NET made this happen, not only for direct access to manipulate data on the server, but also for supporting web-facing applications to interact with the databases. There are two versions, of particular interest to SQL Azure, that are specially highlighted as they allow for creating applications consuming data from the SQL Azure Server. Visual Studio 2008 SP1 and Visual Studio 2010 RC were released (April 12, 2010) recently for production. The new key features of the more recent update to SQL Azure are here: http://hodentek.blogspot.com/2010/04/features-galore-for-sql-azure.html. It may be noted that the SQL Azure portal provides the all-important connection strings that is crucial for connecting to SQL Azure using Visual Studio. VS2008 Although you can access and work with SQL Azure using Visual Studio 2008, it does not support establishing a data connection to SQL Azure using the graphic user interface, like you can with an on-site application. This has been remedied in Visual Studio 2010. VS2010 Visual Studio 2010 has a tighter integration with many more features than Visual Studio 2008 SP1. It is earmarked to make the cloud offering more attractive. Of particular interest to SQL Azure is the support it offers in making a connection to SQL Azure through its interactive graphic user interface and the recently introduced feature supporting Data-tier applications. A summary detail of the data tier applications are here: http://hodentek.blogspot.com/2010/02/working-with-data-gotten-lot-easier.html. SQLBulkCopy for Data Transfer In .NET 2.0, the SQLBulkCopy class in the System.Data.SqlClient namespace was introduced. This class makes it easy to move data from one server to another using Visual Studio. An example is described in the next chapter using Visual Studio 2010 RC, but a similar method can be adopted in Visual Studio 2008.SQL Server Business Development Studio (BIDS). The Business Development Studio (BIDS) would fall under both SQL Server 2008 and Visual Studio. The tight integration of Visual Studio with SQL Server was instrumental in the development of BIDS. Starting off to a successful introduction in Visual Studio 2005 more enhancements were added in Visual Studio 2008, both to the Integration Services as well as Reporting Services, two of the main features of BIDS. BIDS is available as a part of the Visual Studio shell when you install the recommended version of SQL Server. Even if you do not have Visual Studio installed, you would get a part of Visual Studio that is needed for developing business intelligence-related integration services as well as reporting services applications. SQL Server Integration Services Microsoft SQL Server Integration Services (SSIS) is a comprehensive data integration service that superseded the Data Transformation Services. Through its connection managers it can establish connections to a variety of data sources that includes SQL Azure. Many of the data intensive tasks from onsite to SQL Azure can be carried out in SSIS. SQL Server Reporting Services SQL Server Reporting Services (SSRS) is a comprehensive reporting package that consists of a Report Server tightly integrated with SQL Server 2008 R2 and a webbased frontend, client software - the Report Manager. SSRS can spin-off reports from data stored on SQL Azure through its powerful data binding interface. Entity Framework Provider Like ODBC, OLE DB, and ADO.NET data providers Entity Framework also features an Entity Framework Provider although, it does not connect to SQL Azure like the others. Using Entity Framework Provider you can create data services for a SQL Azure database. .NET client applications can access these services. In order to work with Entity Framework Provider you need to install Windows Azure SDK (there are several versions of these), which provides appropriate templates. Presently, the Entity Framework Provider cannot create the needed files for a database on SQL Azure. A workaround is adopted. SQL Server related The tools described in this section can directly access SQL Server 2008 R2. The Export/ Import Wizard cannot only access SQL Servers but also products from other vendors to which a connection can be established. Scripting support, BCP, and SSRS are all effective when the database server is installed and are part of the SQL Server 2008 R2 installation. SQL Server Integration Services is tightly integrated with SQL Server 2008 R2, which can store packages created using SSIS. Data access technologies and self-service business integration technologies are developing rapidly and will impact on cloud-based applications including solutions using SQL Azure. SQL Server Management Studio SQL Server Management Studio (SSMS) has been the work horse with the SQL Servers from the very beginning. SSMS also supports working with SQL Azure Server. SQL Server 2008 did not fully support SQL Azure, except it did enable connection to SQL Azure. This was improved in SQL Server 2008 R2 November-CTP and the versions to appear later. SSMS also provides the SQL Azure template, which includes most of the commands you will be using in SQL Azure. Import/Export Wizard The Import/Export Wizard has been present in SQL Servers even from earlier versions to create DTS packages of a simple nature. It could be started from the command line using DTSWiz.exe or DTSWizard.exe. In the same folder, you can access all dts-related files. You can double-click Import and Export Data (32-bit) in Start | All Programs | Microsoft SQL Server 2008 R2. You may also run the DTSWizard.exe from a DOS prompt to launch the wizard. The Import/Export wizard may be able to connect to SQL Azure using any of the following: ODBC DSN SQL Server Native Client 10.0 .NET Data Source Provider for SqlServer The Import/Export wizard can connect to the SQL Azure server using ODBC DSN. Although connection was possible, the export or import was not possible in the CTP version due to some unsupported stored procedure. Import/Export works with the .NET Framework Data Provider, but requires some tweaking.  

  Microsoft Azure: Enterprise Application Development Straight talking advice on how to design and build enterprise applications for the cloud Build scalable enterprise applications using Microsoft Azure The perfect fast-paced case study for developers and architects wanting to enhance core business processes Packed with examples to illustrate concepts Written in the context of building an online portal for the case-study application Blobs in the Azure ecosystem Blobs are one of the three simple storage options for Windows Azure, and are designed to store large files in binary format. There are two types of blobs—block blobs and page blobs. Block blobs are designed for streaming, and each blob can have a size of up to 200 GB. Page blobs are designed for read/write access and each blob can store up to 1 TB each. If we're going to store images or video for use in our application, we'd store them in blobs. On our local systems, we would probably store these files in different folders. In our Azure account, we place blobs into containers, and just as a local hard drive can contain any number of folders, each Azure account can have any number of containers. Similar to folders on a hard drive, access to blobs is set at the container level, where permissions can be either "public read" or "private". In addition to permission settings, each container can have 8 KB of metadata used to describe or categorize it (metadata are stored as name/value pairs). Each blob can be up to 1 TB depending on the type of blob, and can also have up to 8 KB of metadata. For data protection and scalability, each blob is replicated at least three times, and "hot blobs" are served from multiple servers. Even though the cloud can accept blobs of up to 1 TB in size, Development Storage can accept blobs only up to 2 GB. This typically is not an issue for development, but still something to remember when developing locally. Page blobs form the basis for Windows Azure Drive—a service that allows Azure storage to be mounted as a local NTFS drive on the Azure instance, allowing existing applications to run in the cloud and take advantage of Azure-based storage while requiring fewer changes to adapt to the Azure environment. Azure drives are individual virtual hard drives (VHDs) that can range in size from 16 MB to 1 TB. Each Windows Azure instance can mount up to 16 Azure drives, and these drives can be mounted or dismounted dynamically. Also, Windows Azure Drive can be mounted as readable/writable from a single instance of an Azure service, or it can be mounted as a read-only drive for multiple instances. At the time of writing, there was no driver that allowed direct access to the page blobs forming Azure drives, but the page blobs can be downloaded, used locally, and uploaded again using the standard blob API. Creating Blob Storage Blob Storage can be used independent of other Azure services, and even if we've set up a Windows Azure or SQL Azure account, Blob Storage is not automatically created for us. To create a Blob Storage service, we need to follow these steps: Log in to the Windows Azure Developer portal and select our project. After we select our project, we should see the project page, as shown in the next screenshots: Clicking the New Service link on the application page takes us to the service creation page, as shown next: Selecting Storage Account allows us to choose a name and description for our storage service. This information is used to identify our services in menus and listings. Next, we choose a unique name for our storage account. This name must be unique across all of Azure—it can include only lowercase letters and numbers, and must be at least three characters long. If our account name is available, we then choose how to localize our data. Localization is handled by "affinity groups", which tie our storage service to the data centers in different geographic regions. For some applications, it may not matter where we locate our data. For other applications, we may want multiple affinity groups to provide timely content delivery. And for a few applications, regulatory requirements may mean we have to bind our data to a particular region. Clicking the Create button creates our storage service, and when complete, a summary page is shown. The top half of the summary page reiterates the description of our service and provides the endpoints and 256-bit access keys. These access keys are very important—they are the authentication keys we need to pass in our request if we want to access private storage or add/update a blob. The bottom portion of the confirmation page reiterates the affinity group the storage service belongs to. We can also enable a content delivery network and custom domain for our Blob Storage account. Once we create a service, it's shown on the portal menu and in the project summary once we select a project. That's it! We now have our storage services created. We're now ready to look at blobs in a little more depth.

Moodle as a Curriculum and Information Management System Use Moodle to manage and organize your administrative duties; monitor attendance records, manage student enrolment, record exam results, and much more Transform your Moodle site into a system that will allow you to manage information such as monitoring attendance records, managing the number of students enrolled in a particular course, and inter-department communication Create courses for all subjects in no time with the Bulk Course Creation tool Create accounts for hundreds of users swiftly and enroll them in courses at the same time using a CSV file. Part of Packt's Beginner's Guide series: Readers are walked through each task as they read the book with the end result being a sample CIMS Moodle site Using the Bulk Course Upload tool Rather than creating course categories and then courses one at a time and assigning teachers to each course after the course is created, we can streamline the process through the use of the Bulk Course Upload tool. This tool allows you to organize all the information required to create your courses in a CSV (Comma Separated Values) file that is then uploaded into the creation tool and used to create all of your courses at once. Due to its design, the Bulk Course Upload tool only works with MySQL databases. Our MAMP package uses a MySQL database as do the LAMP packages. If your Moodle site is running on a database of a different variety you will not be able to use this tool. Time for action – installing the Bulk Course Upload tool Now that we have our teacher's accounts created, we are ready to use the Bulk Course Creation tool to create all of our courses. First we need to install the tool as an add-on admin report into our Moodle site. To install this tool, do the following: Go to the Modules and plugins area of www.moodle.org. Search for Bulk Course Upload tool. Click on Download latest version to download the tool to your computer. If this does not download the package to your hard drive and instead takes you to a forum in the Using Moodle course on Moodle.org, download the package that was posted in that forum on Sunday, 11 May 2008. Expand the package, contained within, and find the uploadcourse.php file. Place the uploadcourse.php file in your admin directory located inside your main Moodle directory. When logged in as admin, enter the following address in your browser address bar: http://localhost:8888/moodle19/admin/uploadcourse.php. (If you are not using a MAMP package, the first part of the address will of course be different.) You will then see the Upload Course tool explanation screen that looks like the following screenshot: The screen, shown in the previous screenshot, lists the thirty-nine different fields that can be included in a CSV file when creating courses in bulk via this tool. Most of the fields here control settings that are modified in individual courses by clicking on the Settings link found in the Administration block of each course. The following is an explanation of the fields with notes about which ones are especially useful when setting up Moodle as a CIMS: category: You will definitely want to specify categories in order to organize your courses. The best way to organize courses and categories here is such that the organization coincides with the organization of your curriculum as displayed in school documentation and student handbooks. If you already have categories in your Moodle site, make sure that you spell the categories exactly as they appear on your site, including capitalization. A mistake will result in the creation of a new category. This field should start with a forward slash followed by the category name with each subcategory also being followed by a forward slash (for example, /Listening/Advanced). cost: If students must pay to enroll in your courses, via the PayPal plugin, you may enter the cost here. You must have the PayPal plugin activated on your site, which can be done by accessing it via the Site Administration block by clicking on Courses and then Enrolments. Additionally, as this book goes to print, the ability to enter a field in the file used by the Bulk Course tool that allows you to set the enrolment plugin, is not yet available. Therefore, if you enter a cost value for a course, it will not be shown until the enrolment plugin for the course is changed manually by navigating to the course and editing the course through the Settings link found in the course Administration block. Check Moodle.org frequently for updates to the Bulk Course Upload tool as the feature should be added soon. enrolperiod: This controls the amount of time a student is enrolled in a course. The value must be entered in seconds so, for example, if you had a course that ran for one month and students were to be unenrolled after that period, you would set this value to 2,592,000 (60 seconds X 60 minutes per hour X 24 hours per day X 30 = 2,592,000). enrollable: This simply controls whether the course is enrollable or not. Entering a 0 will render the course unenrollable and a 1 will set the course to allow enrollments. enrolstartdate and enrolenddate: If you wish to set an enrollment period, you should enter the dates (start and end dates) in these two fields. The dates can be entered in the month/day/year format (for example, 8/1/10). expirynotify: Enter a 1 here to have e-mails sent to the teacher when a student is going to be unenrolled from a course. Enter a 0 to prevent e-mails from being sent when a student is going to be unenrolled. This setting is only functional when the enrolperiod value is set. expirythreshold: Enter the number of days in advance you want e-mails notifying of student unenrollment sent. The explanation file included calls for a value between 10 and 30 days but this value can actually be set to between 1 and 30 days. This setting is only functional when the enrolperiod value and expirynotify and/or notifystudents (see below) is/are set. format: This field controls the format of the course. As of Moodle 1.9.8+ there are six format options included in the standard package. The options are lams, scorm, social, topics, weeks, and weeks CSS, and any of these values can be entered in this field. fullname: This is the full name of the course you are creating (for example, History 101). groupmode: Set this to 0 for no groups, 1 for separate groups, and 2 for visible groups. groupmodeforce: Set this to 1 to force group mode at the course level and 0 to allow group mode to be set in each individual activity. guest: Use a 0 to prevent guests from accessing this course, a 1 to allow uests in the course, and a 2 to allow only guests who have the key into the course. idnumber: You can enter a course ID number using this field. This number is only used for administrative purposes and is not visible to students. This is a very useful field for institutions that use identification numbers for courses and can provide a link for connecting the courses within Moodle to other systems. If your institution uses any such numbering system it is recommended that you enter the appropriate numbers here. lang: This is the language setting for the course. Leaving this field blank will result in the Do not force language setting, which can be seen from the Settings menu accessed from within each individual course. Doing so will allow users to toggle between languages that have been installed in the site. To specify a language, and thus force the display of the course using this language, enter the language as it is displayed within the Moodle lang directory (for example, English = en_utf8). maxbytes: This field allows you to set the maximum size of individual files that are uploaded to the course. Leaving this blank will result in the course being created with the site wide maximum file upload size setting. Values must be entered in bytes (for example, 1 MB = 1,048,576 bytes). Refer to an online conversion site such as www.onlineconversion.com to help you determine the value you want to enter here. metacourse: If the course you are creating is a meta course, enter a 1, otherwise enter a 0 or leave the field blank.

  Scribus 1.3.5: Beginner's Guide Create optimum page layouts for your documents using productive tools of Scribus. Master desktop publishing with Scribus Create professional-looking documents with ease Enhance the readability of your documents using powerful layout tools of Scribus Packed with interesting examples and screenshots that show you the most important Scribus tools to create and publish your documents. Creating a new layout Creating a layout in Scribus means dealing with the New Document window. It is not a complex window but be aware that many things you'll set here will be considered definitive. If these settings look simple or evident, you should consider all these settings as important. Some of them like the page size mean that you already have an idea of the final document, or atleast that you've already made some choices that won't change after it is created. Of course, Scribus will let you change this later if you change your mind, but many things you will have done in the meantime will simply have to be done again. Time for action – setting page size and paper size and margins This window is the first that opens when you launch Scribus or when you go to the File | New menu. It contains several options that need to be set. First among these options will certainly be the page size. In our case, people usually use 54x85mm (USA: 51×89mm). When you type the measurements in the Width and Height fields, the Size option, which contains the common size presets, is automatically switched to Custom. If you want to use a different system unit, just change the Default Unit value placed below. Usually, we prefer Millimeters (mm), which is quite precise without having too many significant decimals. Then, you can set the margin for your document. Professional printers are very different from desktop printers as they can print without margins. In fact, consider margins as helpers to place objects. For a small document like a business card, having small 4mm margins will be good. What just happened? Some common page sizes are: the series (the ISO standards biggest starting with A0 841x1189, that is 1m², and halving at each half step), the US formats, especially letter (216x279mm), legal (216x356mm), and tabloid (approximately 279x432mm, 11x17in), commonly used in the UK for newspapers. The best business card size When choosing the size for the business card, you'll consider the existing size often used. Is ISO 54x85.6mm better than the US 2x3.5in, or the European 55x85mm, or the Australian 55x90mm, when only a few millimeters divide them? Best is certainly to match the most commonly-used size in your country. Remember one thing: a business card must have to be easily stored and sorted. Grabbing an uncommon format can just lead to the fact that no one will be able to put your card in their wallet. Presets will be useful if you want to print locally, but don't forget that your print company crops the paper to the size you want. So don't mind being creative and do some testing. For example, you might print on an A3 size paper for your final document or in an A3+ real printing size so that you'll be able to use bleeds, as we'll explain in the following sections. Here we're talking about the page size and not the paper size, which can be double if the Document Layout is set to any option but Single Page. For all the folded documents, the page size differs from the paper size—keep that in mind. For now choose 54x85.6 in landscape: just set 54 as the height or change the orientation button if you haven't. The other setting that might interest you is the margin . In Scribus, consider the margin as a helper. In fact nobody in the professional print process will need margins. It is useful for desktop printers, which can't print up to the sheet border. As our example is much smaller than the usual paper size, we won't have any trouble with it. Scribus has some presets for margins that are available only when a layout other than Single Page is selected. For our model, 4mm to each side will be fine. If you want to set all the fields at once, just click on the chain button at the right-hand side of the margin fields. But actually, we can consider that we won't have much to write and that it would be nice if our margins could help position the text. So let's define the margins as follows: Left: 10mm Right: 40mm Top: 30mm Bottom: 2mm Choosing a layout We've already talked about this option several times but here we are again. What kind of layout would you choose? Single page will simulate what you might have in a text processor. You can have as many pages as you want but it will be printed page after page. You'll get its result when printing with your desktop printer: Double-sided will be the option you'll use when you'll need a folded document. This is useful for magazines, newsletters, books, or such documents. In this layout, the reader will see two pages side by side at once, and you can easily manage elements that will overlap both pages. The fold will be in the exact middle. Usually, unless you have a small document size like A5 or smaller, this layout is intended to be printed by a professional. 3-Fold and 4-Fold are more for commercial little brochures. Usually, you won't use it in Scribus and will prefer a Single Page layout that you'll divide later into three or four parts. Why? Because with the folded out, Scribus will consider each "fold" as a page and will print each of them on a separate sheet—a bit tricky. You can see that for a business card, where no fold is needed, the Single Page layout will be our choice. (Move the mouse over the image to enlarge.) For the moment we won't need other options, so you can click on OK. You'll get a white rectangle on a greyish workspace. The red outline is the selection indicator for the selected page. It shows the borders of the page. The blue rectangle shows where the margins are placed. Save the document as often as possible "Save the document as often as possible"—this is the first commandment of a software user, but in Scribus this is much more important for several reasons: First of all, apologies, Scribus is a very nice piece of software but still not perfect (but which one is?). It can crash sometimes, slightly more than you'd wish, and never at a time you would expect or appreciate. Saving often will help you save a lot of time doing again what you've already achieved during the day. The Scribus undo system acts on layout options but not on text manipulations. Saving often can be helpful if you make mistakes that you can't undo. In Scribus, we will use File | Save As (or Ctrl + Shift + S) to set the document name and format. It's very simple because you have no other choice than Scribus Documents *.sla. In the list, you will see sla.gz that will be used when the Compress File checkbox will be selected. Usually, a Scribus file is not that large in size and there is no real need to compress it. Of course, if the file already exists, Scribus asks whether you want to overwrite the previous one. Scribus file version Each Scribus release has enhanced the file format to be able to store the new possibilities in the file. But when saving, you cannot choose a version: Scribus will always use the current one. Every document can be opened in future Scribus releases but not in the older ones. So be careful when you need to send the file to someone or else when you're working on several computers. Once you've used Saved As, you'll just have to simply save (File | Save) or more magically use Ctrl + S, and the modifications will automatically be added to the saved document. The extra Save as Template menu will store the actual file in a special Scribus folder. When you want to create a new document with the same global aspect, you can go to the New from Template menu and grab it from the list. There are some default templates available here, but yours might be better. Saving as a template might not be the usual saving process; this is done at the end when the basics of your layout have been made. Saving as template must happen only once for a template. So we'll use it at the end of our tutorial. Basic frames for text and images The biggest part of a design job is adding frames, setting their visual aspect, and importing content into them. In our business card we'll need a logo, name, and other information. You may add a photo. Time for action – adding the logo They are several types of graphic elements in a layout. The logo is of course one of the most important. Generally, we prefer using vector logos in SVG or EPS. Let's import a logo. In the File menu choose File | Import | Get Vector File. The cursor has now been changed, and you can click on the page where you want to place the logo. Try to click at the upper-left corner of the margins. It will certainly not be correctly placed and the logo may be too big. We'll soon see how to change it. A warning will appear and inform you that some SVG features will not be supported. There is no option other than clicking on OK, and everything should be good. What just happened? The logo is the master piece of the card. It helps recognize the origin of the contact. In some ways, it is the most important recognition for a company. Usually, a logo is the only graphical element on the card. It can be put anywhere you want, but generally the upper left-hand side corner is the place of choice.  

Packt Enterprise's Book of the Moment Packt Enterprise's book of the moment has been named as... Applied Architecture Patterns on the Microsoft Platform This book has been awarded Packt Enterprise's Book of the Moment

Django JavaScript Integration: AJAX and jQuery Develop AJAX applications using Django and jQuery Learn how Django + jQuery = AJAX Integrate your AJAX application with Django on the server side and jQuery on the client side Learn how to handle AJAX requests with jQuery Compare the pros and cons of client-side search with JavaScript and initializing a search on the server side via AJAX Handle login and authentication via Django-based AJAX This will allow us to create a results page as shown: When someone clicks OK, the data is saved on the server, and also shown on the page. Let's get started on how this works. Including a plugin We include a jQuery plugin on a page by including jQuery, then including the plugin (or plugins, if we have more than one). In our base.html, we update: {% block footer_javascript_site %} <script language="JavaScript" type="text/javascript" src="/static/js/jquery.js"></script> <script language="JavaScript" type="text/javascript" src="/static/js/jquery-ui.js"></script> <script language="JavaScript" type="text/javascript" src="/static/js/jquery.jeditable.js"></script> {% endblock footer_javascript_site %} This is followed by the footer_javascript_section and footer_javascript_page blocks. This means that if we don't want the plugin ,which is the last inclusion, to be downloaded for each page, we could put it in overridden section and page blocks. This would render as including the plugin after jQuery. How to make pages more responsive We would also note that the setup, with three JavaScript downloads, is appropriate for development purposes but not for deployment. In terms of YSlow client-side performance optimization, the recommended best practice is to have one HTML/XHTML hit, one CSS hit at the top, and one JavaScript hit at the bottom. One of the basic principles of client-side optimization, discussed by Steve Souders (see http://developer.yahoo.com/yslow/) is,since HTTP requests slow the page down, the recommended best practice is to have one (preferably minifed) CSS inclusion at the top of the page, and then one (preferably minifed) JavaScript inclusion at the bottom of each page. Each HTTP request beyond this makes things slower, so combining CSS and/or JavaScript requests into a single concatenated file is low-hanging fruit to improve how quick and responsive your web pages appear to users. For deployment, we should minify and combine the JavaScript. As we are developing, we also have JavaScript included in templates and rendered into the delivered XHTML; this may be appropriate for development purposes. For deployment though, as much shared functionality as possible should be factored out into an included JavaScript fle. For content that can be delivered statically, such as CSS, JavaScript, and even non-dynamic images, setting far-future Expires/Cache-Control headers is desirable. (One practice is to never change the content of a published URL for the kind of content that has a far-future expiration set, and then if it needs updating, instead of changing the content at the same location, leave the content where it is, publish at a new location possibly including a version number, and reference the new location.) A template handling the client-side requirements Here's the template. Its view will render it with an entity and other information. At present it extends the base directly; it is desirable in many cases to have the templates that are rendered extend section templates, which in turn extend the base. In our simple application, we have two templates which are directly rendered to web pages. One is the page that handles both search and search results—and the other, the page that handles a profile, from the following template: {% extends "base.html" %} We include honorifics before the name, and post-nominals after. At this point we do not do anything to make it editable. {% extends "base.html" %} Following earlier discussion, we include honorifcs before the name, and post-nominals after. At this point we do not do anything to make it editable. {% block head_title %} {{ entity.honorifics }} {{ entity.name }} {{ entity.post_nominals }} {% endblock head_title %} {% block body_main %} There is one important point about Django and the title block. The Django developers do not fnd it acceptable to write a templating engine that produces errors in production if someone attempts to access an undefned value (by typos, for instance). As a result of this design decision, if you attempt to access an undefned value, the templating engine will silently insert an empty string and move on. This means that it is safe to include a value that may or may not exist, although there are ways to test if a value exists and is nonempty, and display another default value in that case. We will see how to do this soon. Let's move on to the main block, defned by the last line of code. Once we are in the main block, we have an h1 which is almost identical to the title block, but this time it is marked up to support editing in place. Let us look at the honorifics span; the name and post_nominals spans work the same way: <h1> <span id="Entity_honorifics_{{ entity.id }}" class="edit"> {% if entity.honorifics %} {{ entity.honorifics }} {% else %} Click to edit. {% endif %} </span> The class edit is used to give all $(".edit") items some basic special treatment with Jeditable; there is nothing magical about the class name, which could have been replaced by user-may-change-this or something else. edit merely happens to be a good name choice, like almost any good variable/function/object name. We create a naming convention in the span's HTML ID which will enable the server side to know which—of a long and possibly open-ended number of things we could intend to change—is the one we want. In a nutshell, the convention is modelname_feldname_instanceID. The frst token is the model name, and is everything up to the first underscore. (Even if we were only interested in one model now, it is more future proof to design so that we can accommodate changes that introduce more models.) The last token is the instance ID, an integer. The middle token, which may contain underscores (for example post_nominals in the following code), is the feld name. There is no specifc requirement to follow a naming convention, but it allows us to specify an HTML ID that the server-side view can parse for information about which feld on which instance of which model is being edited. We also provide a default value, in this case Click to edit, intended not only to serve as a placeholder, but to give users a sense on how this information can be updated. We might also observe that here and in the following code, we do not presently have checks against race conditions in place. So nothing here or in the following code will stop users from overwriting each others' changes. This may be taken as a challenge to refne and extend the solution to either prevent race conditions or mitigate their damage. <span id="Entity_name_{{ entity.id }}" class="edit"> {% if entity.name %} {{ entity.name }} {% else %} Click to edit. {% endif %} </span> <span id="Entity_post_nominals_{{ entity.id }}" class="edit"> {% if entity.post_nominals %} {{ entity.post_nominals }} {% else %} Click to edit. {% endif %} </span> </h1> This approach is an excellent frst approach but in practice is an h1 with three slots that say Click to edit on a profle, creating needless confusion. We move to a simplifed: <span id="Entity_name_{{ entity.id }}" class="edit"> {% if entity.name %} {{ entity.name }}jQuery In-place Editing Using Ajax {% else %} Click to edit. {% endif %} </span> <span id="Entity_post_nominals_{{ entity.id }}" class="edit"> {% if entity.post_nominals %} {{ entity.post_nominals }} {% else %} Click to edit. {% endif %} </span> </h1> Taken together, the three statements form the heading in this screenshot: If we click on the name (for instance) it becomes: The image is presently a placeholder; this should be expanded to allow an image to be uploaded if the user clicks on the picture (implementing consistent-feeling behavior whether or not we do so via the same plugin). We also need the view and urlpattern on the backend: <h1 class="edit" id="Entity_name_{{ entity.id }}"> {{ entity.name }} </h1>

Scribus 1.3.5: Beginner's Guide Create optimum page layouts for your documents using productive tools of Scribus. Master desktop publishing with Scribus Create professional-looking documents with ease Enhance the readability of your documents using powerful layout tools of Scribus Packed with interesting examples and screenshots that show you the most important Scribus tools to create and publish your documents.   Resizing objects Well it's time to work on the logo: it's really big and we would like it to be aligned the top part of the card. There are several ways to resize an object or frame. Resizing with the mouse When an object is selected, for example, click on the logo, and you can see a red rectangle outline. This doesn't affect the object properties but only shows that it is selected. There are little red square handles at each corner and at the middle of each side. If the mouse gets over one of these handles, the cursor will change to a double arrow. If you press the left mouse button when the pointer is on one of them and then move the pointer, you'll see the size changing according to the mouse movements. Just release the button when you're done. While resizing the frame an information box appears near the pointer and displays the new width. You will notice that the proportions of the object are not kept, and that the logo is modified. To avoid this, just press the Ctrl key while dragging the handles and you'll see that the logo will be scaled proportionally. Resizing with the Properties Palette As an alternative, you can use the Width and Height fields of the XYZ tab in the Properties Palette. If you need to keep the ratio, be sure that the chain button at the right-hand side of the field is activated. You can set the size in three ways: By scrolling the mouse wheel within the field. Pressing Ctrl or Shift while scrolling will increase or decrease the effect. If you already know the size, you can directly write it. This is mostly the case when you have a graphical charter that defines it or when you're already recreating an existing document. You can also use the small arrows at the right-hand side of the field (the same modifiers apply as described for the mouse wheel). Resizing with the keyboard Another way to resize objects is by using the keyboard. It's useful when you're typing and you need some extra space to put some more text, and that don't want to put your hands on the mouse. In this case, just: Press Esc to enter the Layout mode and leave the Content mode Press Alt and one of the arrows at the same time Press E to go back to Content Edit mode If you do some tests, you'll find that each arrow controls a side: the left arrow affects the size by moving the left-hand side, the right arrow affects the right-hand side, and so on. You can see that with this method the shape can only grow. Have a go hero – vector circle style Since the past two or three years, you might have noticed that shapes are being used in their pure form. For example, check this easy sample and try to reproduce it in the best way you can: copy-paste, moving, and resizing are all you'll need to know. Scaling objects Scaling objects—what can be different here from resizing? Once more, it's on Text Frames that the difference is more evident. Compare the results you can get: The difference is simple: in the top example the content has been scaled with the frame, and in the second only the frame is scaled. So it's scaling the content. You can scale a Text Frame (with its consent) by pressing the Alt key while resizing with the mouse. The Alt key applies, as always, while the mouse is pressed during the resizing movement. So did you see something missing in our card? Time for action – scaling the name of our company Let's say that our company name is "GraphCo" as in the previous image and that we want to add it to the card. Take the Insert Text Frame tool and draw a little frame in the page. An alternative could be clicking on the page instead of dragging. Once you've clicked, the Object Size window is displayed and you can set 12mm or so as width, and 6mm as the height. Then click on OK to create the frame. Double-click in the frame and type the name of the company. Select the text and change the font family to one that you like (here the font is OpenDINSchriftenEngShrift), and decrease the size if the name is not completely visible. Scale the frame until it is about 50mm wide. We can fix the width later. What just happened? Most of the time, you will use simple resizing instead of scaling. When you want the text to match some area and you don't want to play indefinitely with the font size setting, you may prefer to use the scaling functionality. Using the scale options makes it very easy to resize the frame and the text visually without trying to find the best font size in pt, which can sometimes be quite long.  

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Drupal Intranets with Open Atrium Discover an intranet solution for your organization with Open Atrium Unlock the features of Open Atrium to set up an intranet to improve communication and workflow Explore the many features of Open Atrium and how you can utilize them in your intranet Learn how to support, maintain, and administer your intranet A how-to guide written for non-developers to learn how to set up and use Open Atrium   Main dashboard The main dashboard provides an interface for managing and monitoring our Open Atrium installation. This dashboard provides a central place to monitor what's going on across our departments. It will also be used as the central gateway for most of our administrative tasks. From this screen we can add groups, invite users, and customize group dashboards. Each individual who logs in also has the main dashboard and can quickly glance at the overall activity for their company. The dashboard is laid out initially by default in a two column layout. The left side of the screen contains the Main Content section and the right side of the screen contains a Sidebar. In a default installation of Open Atrium, there will be a welcome video in the Main Content area on the left. The first thing that you will notice when you log in is that there is a quick video that you can play on your main dashboard screen. This video provides a quick overview of Open Atrium for our users, and a review of the options you have for working with the dashboard. In the following screenshot, you will see the main dashboard and how the two separate content areas are divided, with a specific section marked that we will discuss later in the article: Each dashboard can be customized to either a two-column or split layout, as shown in the preceding screenshot, or a three-column layout. Under the Modifying Layout section of this article, we will cover how to change the overall layout. As you can see in the preceding image, the dashboard is divided into three distinct sections. There is the header area which includes the Navigation tabs for creating content, modifying settings, and searching the site. Under the header area, we have the main content and sidebar areas. These areas are made up of blocks of content from the site. These blocks can bring forward and include different items depending on how we customize our site. For example, in the left column we could choose to display Recent Activity and Blog Posts, while the right column could show Upcoming Events and a Calendar. Any of the features that we find throughout Open Atrium can be brought forward to a dashboard page. The beauty of this setup is that each group can customize their own. In the next section of this article, we will cover group dashboards in more detail. However, the same basic concepts will apply to all the dashboards. After our users are comfortable with using Open Atrium, we may decide that we no longer need to show the tutorial video on the main dashboard. This video can be easily removed by clicking on the Customizing the dashboard link just above the Recent Activity block or by clicking on the Customize dashboard link on the top right in the header section. Click on the customizing the dashboard link and we will see a dashboard widget on the screen. This will be the main interface for configuring layout and content on our dashboard. Now, hover over the video and on the top right you will see two icons. The first icon that looks like a plus sign (+) indicates that the content can be dragged. We can click on this icon when hovering over a section of content and move that content to another column or below another section of content on our dashboard. The X indicates that we can remove that item from our dashboard. Hovering over any piece of content when you are customizing the dashboard should reveal these two icons. The two icons are highlighted in the following screenshot with a square box drawn around them: To remove the welcome video, we click on the red X and then click on Save changes and the video tutorial will be removed from the dashboard. Group dashboard The group dashboard works the same as the main dashboard. The only difference is that the group dashboard exposes content for the individual departments or groups that are setup on our site. For example, a site could have a separate group for the Human Resources, Accounting, and Management departments. Each of these groups can create a group dashboard that can be customized by any of the administrators for a particular group. The following screenshot shows how the Human Resources department has customized their group dashboard:   In the preceding screenshot, we can see how the HR department customized their dashboard. In the left column they have added a Projects and a Blog section. The Projects section links to specific projects within the site, and the Blog section links to the detailed blog entries. There is also a customized block in the right column where the HR department has added the Upcoming events, a Mini calendar, and a Recent activity block. The Projects section is a block that is provided by the system and exposes content from the Case tracker or Todo sections of the HR website. The Upcoming events section is a customized block that highlights future events entered through the calendar feature. To demonstrate how each department can have a different dashboard, the following screenshot shows the dashboard for the Accounting department: The Accounting dashboard has been configured to show a custom block as the first item in the left column, and below that a listing of Upcoming events. In the right column, the Accounting administrator has added a block which brings forward the Latest cases of all the latest cases, exposing the most recent issues entered into the tracking system. It is also worth noting that the Accounting department has a completely different color scheme from the Human Resources department. The color scheme can be changed by clicking on Settings | Group Settings | Features. We can scroll down to the bottom of the screen and click on BACKGROUND to either enter a hexadecimal color for our main color or pick a color from the color wheel as displayed in the following screenshot: Spaces Spaces is a Drupal API module that allows sitewide configurable options to be overridden by individual spaces. The spaces API is included with our Open Atrium installation and provides the foundation for creating group and user configurable dashboards. Users can then customize their space and set settings that are only applied to their space. This shows the extreme power and flexibility of Open Atrium by allowing users to apply customizations without affecting any of the other areas of Open Atrium. Users can use the functionality provided by spaces to create an individualized home page. Group spaces Group spaces provide an area for each group or department to arrange content in a contextual manner that makes sense for each group. In the preceding examples, the content that is important to the accounting department is not necessarily important to the human resources department. Administrators of each department can take advantage of Open Atrium's complete flexibility to arrange content in a way that works for them. The URLs in the example that we have been looking at are listed as follows: Human Resources: http://acme.alphageekdev.com/hr. Accounting: http://acme.alphageekdev.com/acct Each URL is composed of the site URL, that is, http://acme.alphageekdev.com/ and then the short name that we provided for our group space, hr and acct. User spaces User spaces work in the same way that the group dashboard and spaces work. Each user of the system can customize their dashboard any way that they see appropriate. The following screenshot shows an example of the user's dashboard for the admin account: In the preceding screenshot, we have drawn a box around two areas. These two areas represent two different group spaces showing on the user's dashboard page. This shows how content can be brought forward to various dashboards to show only what is important to a particular user.

Mahara 1.2 E-Portfolios: Beginner's Guide Create and host educational and professional e-portfolios and personalized learning communities Create, customize, and maintain an impressive personal digital portfolio with a simple point-and-click interface Set customized access to share your text files, images, and videos with your family, friends, and others Create online learning communities and social networks through groups, blogs, and forums A step-by-step approach that takes you through examples with ample screenshots and clear explanations Q: What will you need to install Mahara? A: Before you can install Mahara, you will need to have access to a Linux server. It may be that you run Linux on a laptop or desktop at home or that your company or institution has its own Linux servers, in which case, great! If not, there are many hosting services available on the Internet, which will enable you to access a Linux server and therefore run Mahara. It is important that you get a server to which you have root access. It is also important that you set your server up with the following features: Database: Mahara must have a database to work. The databases supported are PostgreSQL Version 8.1 or later and MySQL Version 5.0.25 or later. The Mahara developers recommend that you use PostgreSQL, if possible, but for most installations, MySQL will work just as well. PHP: Mahara requires PHP Version 5.1.3 or later. Web Server: The preferred web server is Apache. PHP extensions: Compulsory Extensions: GD, JSON, cURL, libxml, SimpleXML, Session, pgSQL or Mysqli, EXIF, OpenSSL or XML-RCP (for networking support) Optional Extension: Imagick Q: Can Mahara be installed on Windows? A: At the moment, the Mahara developers offer no support for running Mahara on Windows Servers. It is designed to primarily work with Linux, Apache, PHP, and open source SQL databases. Q: What are Views in Mahara? How are they different from Blogs? A: They are one of the stand-out features of Mahara and we think you are really going to enjoy learning to use them. Views, like blogs, are an excellent tool for reflection. The difference between the two is that a blog is very text orientated with a user reflecting on a topic in writing (with usually an odd image or video to supplement the text), but Views allow you to express your ideas in more of a "web page" type format using lots of different blocks. Also, Views are flexible; you can very easily add and remove whichever blocks you want. Q: What are some of the things you can do with Views in Mahara? A: Let's think about some of the things you can do with Views in Mahara: You could present all of your ideas related to one of the topics in a qualification you are taking. This could be for your own reference or you may choose to share access to this View with your tutor or classmates. You could use a View to take notes on all of the thoughts, ideas, links, and so on, that you gather while you are attending a conference (if you have a wireless connection). You can then share the View with your colleagues after the event to show them what you have learned. You could use a View to explore and express your thoughts on a particular aspect of your social or family life, such as a family holiday. This is likely to be private, and something you would only share with other members of your family. You could use a View as a tutor to present all of the important materials your learners need to read, watch, listen to, and think about in preparation for a particular topic they are going to study with you. Lots of lecturers prefer to use Mahara to present their work instead of doing so in a Virtual Learning Environment such as Moodle. This may be partly because the lecturer's name (and avatar) will continue to be associated with the work presented in the Mahara View even after they retire or move on to another academic institution. You could use a View to present an ongoing progress report on a project you are doing at work. You might make a blog post an element of this View as well as make important files related to your project available for sharing. Q: What is a secret URL? A: It is used if you would like to give some people who aren't already members of the Mahara site access to your View. The URL is simply a link to the View, which you can set up as a hyperlink in another web page, in a blog, or e-mail so that others can open it. The URL that is created is difficult to guess so that the general public can't see your View. Rather than use it as a hyperlink, you could just send the whole link to the people you would like to give access to the View by pasting it into an e-mail, for example. Q: When can the View feedback be useful? A: This might be useful in the following situations: You might have asked a peer for feedback on some work you are doing on a particular course in exchange for feedback you can give on their work. A tutor may have added your View to their Watchlist. You may then get some informal feedback from your tutor on your work before you submit it for formal assessment. You could be using the feedback functionality as a communication vehicle. You may raise a topic for discussion with your workmates, for example, and get them to answer the core question(s) posed in your View by using the feedback option. You may have used a View to share highlights of a recent holiday experience with your friends in Mahara. They could then use the feedback option to tell you how jealous they are of your rich experiences or at least of your suntan! Q: How can the Mahara partners help you? A: Mahara partners can help you with hosting, theming, training, coding, tweaking, extending, bug-fixing, problem-resolving, implementation consultancies, and, well, just about anything to do with Mahara, if you ask them nicely enough. All Mahara partners are excellent support agencies and, if you ARE really keen on using Mahara, you really should give one of the partners a shout. Q: What are the steps to join the Mahara Community? A: The steps to join the Mahara Community are as follows: Go and register: The very first thing that anyone will do on your Mahara site is log in. Head on over to http://mahara.org and click the option to Register, a small link, which you will find in the pale blue Login butt on in the top right-hand part of the screen. Once you've registered you can log in. Respond to your e-mail: You will need to confirm your registration by clicking the link that has been sent to your e-mail address. Once you have done this, you will find yourself at http://mahara.org, which is itself a Mahara site. Let's find some people!: Click on the Community tab, and then on the Members tab. Now let's see if you can find the authors! Can you see the Query box? Type in my name Derrin and see if you can find me? Let's look at some views: Now you've found me, click on my name and why not click on one of my views? Here's another example of Mahara in action. Join a forum: Click on the Community tab again, and now on the Forums tab. Can you see the Support forum? Its description is Need help using or installing Mahara? Ask your questions here. That's going to be useful to you, I bet! Why not subscribe to this forum by clicking on the Subscribe button. You will now be e-mailed with all the updates to this forum. Maybe there are other forums you might want to subscribe to. If you just want to browse a forum, just click on the name of the forum and you will be taken to a list of the posts. Have a look at the Mahara partners: Click on the Partners tab.

This book is a fantastic new edition to the current Packt Enterprise range. Written by Marius Vilemaitis, this is a step-by-step guide on how to implement, maintain, and expand the NNMi management tool. It is aimed at Monitoring solution designers, Network engineers, System administrators and Network monitoring operators.  

  Drupal 7 First Look Learn the new features of Drupal 7, how they work and how they will impact you Get to grips with all of the new features in Drupal 7 Upgrade your Drupal 6 site, themes, and modules to Drupal 7 Explore the new Drupal 7 administration interface and map your Drupal 6 administration interface to the new Drupal 7 structure Complete coverage of the DBTNG database layer with usage examples and all API changes for both Themes and Modules Also includes an Appendix that introduces the beta release for Drupal 7. It is not a part of the book (print or e-book) but only available for free download Appendix         Read more about this book       Q: What is Drupal?A: Drupal is an Open Source Content Management System used for building dynamic websites.   Q: Why should I use Drupal and not any other CMS?A: By building on relevant standards and open source technologies, Drupal supports and enhances the potential of the Internet as a medium where diverse and geographically separated individuals and groups can collectively produce, discuss, and share information and ideas. With a central interest in and focus on communities and collaboration, Drupal's flexibility allows the collaborative production of online information systems and communities.   Q: What are the minimum requirements for Drupal 7?A: Drupal 7 requires PHP 5.2.0 or later to run the Drupal code. You will also need one of the following databases to run Drupal 7: MySQL version 5.0 or later PostgreSQL 8.3 or later SQLite 3.4.2 or later   Q: Where can one download Drupal 7 from?A: Head on over to http://drupal.org/project/drupal and click on the Drupal version number you wish to download—in this case it is Drupal 7. Click on Download and then save it to your C: drive or your My Documents folder (or wherever you want).   Q: What's new in Drupal 7?A: There are several key functionalities that made it to Drupal 7. Some of them are as follows: New administration toolbar and overlay administration: After installing Drupal 7 you will notice the new administration toolbar (shown in the following screenshot) that appears on all pages if you have the permission to administer the site: (Move the mouse over the image to enlarge it.) The toolbar groups commonly used tasks together making it easier for new administrators to learn how to configure Drupal and making it quicker for experienced administrators to get to commonly-used functionality. New Field API: The Field API allows site administrators to add additional attributes to a node type. It also supports translatable fields to allow for multi-lingual sites. Added context information to messages during translation: Drupal 7 adds an optional context for the translation to allow developers and themers to make translatable strings less ambiguous. Built-in automated cron functionality: Drupal 7 includes a new cron system that does not rely on running cron from the Unix cron system. The mechanism used is similar to the one used by poormanscron except that it runs from an AJAX request rather than delaying the response time of the page triggering cron. Added a new plugin manager: The plugin manager allows automatic updates of your Drupal installation. Seven theme for administration: A common complaint of Drupal administrators in previous versions was the look of the administration interface and that it could be difficult to tell when you were in the administration interface, since it used the same theme as regular content by default. To fix this, Drupal 7 has added a new administration theme called the Seven theme that is enabled by default. jQuery UI to core: jQuery UI (http://jqueryui.com) is a powerful JavaScript library that includes common controls like calendars, progress bars, tabs, sliders, and more. It also includes functionality to allow drag and drop, resizing, sorting, selection, and more. New Stark theme: The new Stark theme that is designed to make it easier to learn how to build a custom theme. Rewritten database layer (DBTNG): The biggest change in Drupal 7, at least for developers, is the new database layer, also called DBTNG (short for Database Layer: The Next Generation). DBTNG is a big change for developers since it changes how modules interact with the database. Queue API for long-running tasks: Drupal 7 adds a Queue API to manage long-running tasks. In general, any task that takes more than 30 seconds to a minute would be an excellent candidate for the Queue API. New test framework: Drupal 7 adds a comprehensive test framework called testing that allows developers and site administrators to run tests against an existing Drupal installation to ensure that it is behaving properly.   Q: How has the installation process improved in Drupal 7?A: Drupal 7 has a new installation routine. It is designed to make it easier for new Drupal users to set up Drupal. The new installation offers two types of install—the regular installation and a minimal installation.   The Minimal installation is similar to previous versions. The new Standard installation automatically enables commonly-used functionality during the installation to save time after setup.   Q: How has the interface for creating content and new content types improved in Drupal 7?A: Improved interface for creating content: A big, but welcome, change for editors is the redesigned and updated interface to create and edit content. A sample of the interface is shown in the following screenshot:   The redesigned screen makes it easier to quickly navigate to specific sections within the content. Improved interface for creating new content types: The interface for creating content types has been redesigned to keep all of the options in a smaller space so navigation is easier and all information can be quickly accessed.

  Cocos2d for iPhone 0.99 Beginner's Guide Make mind-blowing 2D games for iPhone with this fast, flexible, and easy-to-use framework! A cool guide to learning cocos2d with iPhone to get you into the iPhone game industry quickly Learn all the aspects of cocos2d while building three different games Add a lot of trendy features such as particles and tilemaps to your games to captivate your players Full of illustrations, diagrams, and tips for building iPhone games, with clear step-by-step instructions and practical examples         Read more about this book       (For more resources on Cocos2d, see here.) Handling accelerometer input Now that we have our three basic elements roughly defined, let's focus on the player's interaction with the hero. We will start by allowing the player to move the hero using the device's built-in accelerometer. The accelerometer opens a new world of interaction between the user and the device, allowing for a lot of interesting uses. There are already lots of applications and games that use this feature in innovative ways. For example, in the game Rolando, players have to roll the main character around using the accelerometer, and here we will be doing something similar to that. The accelerometer gives you data of the current tilting of the device in the three axes, that is the x, y, and z axes. Depending on the game you are making, you will be needing all that data or just the values for one or two of the axis. Fortunately, Apple has made it very easy for developers to access the data provided by the accelerometer hardware. Time for action – moving your hero with the accelerometer We have to add a few lines of code in order to have our hero move. The end result will be the hero moving horizontally when the user tilts the device to the left or to the right. We will also do some checkovers, in order to avoid the hero moving out of the screen. The first step involved in using the accelerometer is to enable it for the CCLayers that want to receive its input. Add the following line of code to the GameLayer's init method: self.isAccelerometerEnabled = YES; Then we have to set the update interval for the accelerometer. This will set the interval at which the hardware delivers the data to the GameLayer. Add the following line afterwards: [[UIAccelerometer sharedAccelerometer] setUpdateInterval:(1.0 / 60)]; Now that our GameLayer is prepared to receive accelerometer input, we just have to implement the method that receives and handles it. The following is the method that receives the input and makes our hero move. Add it to the GameLayer class: - (void)accelerometer:(UIAccelerometer*)accelerometer didAccelerate:(UIAcceleration*)acceleration{ static float prevX=0, prevY=0; #define kFilterFactor 0.05f float accelX = (float) acceleration.x * kFilterFactor + (1- kFilterFactor)*prevX; prevX = accelX;//If the hero object exists, we use the calculated accelerometer values to move him if(hero) {//We calculate the speed it will have and constrain it so it doesn't move faster than he is allowed to float speed = -20 * -accelX; if(speed > hero.movementSpeed) speed = hero.movementSpeed; else if(speed < -hero.movementSpeed) speed = -hero.movementSpeed;//We also check that the hero won't go past the borders of the screen, if he would exit the screen we don't move it if((accelX >0 || hero.mySprite.position.x >hero.mySprite.textureRect.size.width / 2) && ( accelX <0 ||hero.mySprite.position.x <320- hero.mySprite.textureRect.size.width / 2)) [hero.mySprite setPosition:ccp(hero.mySprite.position.x +speed,hero.mySprite.position.y)]; }} Run the game now. You should be able to move the hero by tilting you device, as shown in the following screenshot: The iPhone simulator does not provide a way to simulate accelerometer input, so you won't be able to test it in there; it won't move at all. What just happened? Accelerometer input can be achieved quite easily and fast. In our example, we just used the x component of the accelerometer input to handle the hero's position. The accelX variable holds the current value of the x component. This value ranges from -1 to 1, so we multiply it by the speed of the hero, then we just add that result to the current position of the hero, giving the sense of motion. We are also checking to make sure that the hero is not going off the screen before applying that movement.

Python Geospatial Development If you want to follow through the examples in this article, make sure you have the following Python libraries installed on your computer: GDAL/OGR version 1.7 or later (http://gdal.org) pyproj version 1.8.6 or later (http://code.google.com/p/pyproj) Shapely version 1.2 or later (http://trac.gispython.org/lab/wiki/Shapely) Reading and writing geo-spatial data In this section, we will look at some examples of tasks you might want to perform that involve reading and writing geo-spatial data in both vector and raster format. Task: Calculate the bounding box for each country in the world In this slightly contrived example, we will make use of a Shapefile to calculate the minimum and maximum latitude/longitude values for each country in the world. This "bounding box" can be used, among other things, to generate a map of a particular country. For example, the bounding box for Turkey would look like this: Start by downloading the World Borders Dataset from:   http://thematicmapping.org/downloads/world_borders.php Decompress the .zip archive and place the various files that make up the Shapefile (the .dbf, .prj, .shp, and .shx files) together in a suitable directory. We next need to create a Python program that can read the borders of each country. Fortunately, using OGR to read through the contents of a Shapefile is trivial: import osgeo.ogr shapefile = osgeo.ogr.Open("TM_WORLD_BORDERS-0.3.shp") layer = shapefile.GetLayer(0) for i in range(layer.GetFeatureCount()): feature = layer.GetFeature(i) The feature consists of a geometry and a set of fields. For this data, the geometry is a polygon that defines the outline of the country, while the fields contain various pieces of information about the country. According to the Readme.txt file, the fields in this Shapefile include the ISO-3166 three-letter code for the country (in a field named ISO3) as well as the name for the country (in a field named NAME). This allows us to obtain the country code and name like this: countryCode = feature.GetField("ISO3") countryName = feature.GetField("NAME") We can also obtain the country's border polygon using: geometry = feature.GetGeometryRef() There are all sorts of things we can do with this geometry, but in this case we want to obtain the bounding box or envelope for the polygon: minLong,maxLong,minLat,maxLat = geometry.GetEnvelope() Let's put all this together into a complete working program: # calcBoundingBoxes.py import osgeo.ogr shapefile = osgeo.ogr.Open("TM_WORLD_BORDERS-0.3.shp") layer = shapefile.GetLayer(0) countries = [] # List of (code,name,minLat,maxLat, # minLong,maxLong) tuples. for i in range(layer.GetFeatureCount()): feature = layer.GetFeature(i) countryCode = feature.GetField("ISO3") countryName = feature.GetField("NAME") geometry = feature.GetGeometryRef() minLong,maxLong,minLat,maxLat = geometry.GetEnvelope() countries.append((countryName, countryCode, minLat, maxLat, minLong, maxLong)) countries.sort() for name,code,minLat,maxLat,minLong,maxLong in countries: print "%s (%s) lat=%0.4f..%0.4f, long=%0.4f..%0.4f" % (name, code,minLat, maxLat,minLong, maxLong) Running this program produces the following output: % python calcBoundingBoxes.py Afghanistan (AFG) lat=29.4061..38.4721, long=60.5042..74.9157 Albania (ALB) lat=39.6447..42.6619, long=19.2825..21.0542 Algeria (DZA) lat=18.9764..37.0914, long=-8.6672..11.9865 ... Task: Save the country bounding boxes into a Shapefile While the previous example simply printed out the latitude and longitude values, it might be more useful to draw the bounding boxes onto a map. To do this, we have to convert the bounding boxes into polygons, and save these polygons into a Shapefile. Creating a Shapefile involves the following steps: Define the spatial reference used by the Shapefile's data. In this case, we'll use the WGS84 datum and unprojected geographic coordinates (that is, latitude and longitude values). This is how you would define this spatial reference using OGR: import osgeo.osr spatialReference = osgeo.osr.SpatialReference() spatialReference.SetWellKnownGeogCS('WGS84') We can now create the Shapefile itself using this spatial reference: import osgeo.ogr driver = osgeo.ogr.GetDriverByName("ESRI Shapefile") dstFile = driver.CreateDataSource("boundingBoxes.shp")) dstLayer = dstFile.CreateLayer("layer", spatialReference) After creating the Shapefile, you next define the various fields that will hold the metadata for each feature. In this case, let's add two fields to store the country name and its ISO-3166 code: fieldDef = osgeo.ogr.FieldDefn("COUNTRY", osgeo.ogr.OFTString) fieldDef.SetWidth(50) dstLayer.CreateField(fieldDef) fieldDef = osgeo.ogr.FieldDefn("CODE", osgeo.ogr.OFTString) fieldDef.SetWidth(3) dstLayer.CreateField(fieldDef) We now need to create the geometry for each feature—in this case, a polygon defining the country's bounding box. A polygon consists of one or more linear rings; the first linear ring defines the exterior of the polygon, while additional rings define "holes" inside the polygon. In this case, we want a simple polygon with a square exterior and no holes: linearRing = osgeo.ogr.Geometry(osgeo.ogr.wkbLinearRing) linearRing.AddPoint(minLong, minLat) linearRing.AddPoint(maxLong, minLat) linearRing.AddPoint(maxLong, maxLat) linearRing.AddPoint(minLong, maxLat) linearRing.AddPoint(minLong, minLat) polygon = osgeo.ogr.Geometry(osgeo.ogr.wkbPolygon) polygon.AddGeometry(linearRing) You may have noticed that the coordinate (minLong, minLat)was added to the linear ring twice. This is because we are defining line segments rather than just points—the first call to AddPoint()defines the starting point, and each subsequent call to AddPoint()adds a new line segment to the linear ring. In this case, we start in the lower-left corner and move counter-clockwise around the bounding box until we reach the lower-left corner again:   Once we have the polygon, we can use it to create a feature: feature = osgeo.ogr.Feature(dstLayer.GetLayerDefn()) feature.SetGeometry(polygon) feature.SetField("COUNTRY", countryName) feature.SetField("CODE", countryCode) dstLayer.CreateFeature(feature) feature.Destroy() Notice how we use the setField() method to store the feature's metadata. We also have to call the Destroy() method to close the feature once we have finished with it; this ensures that the feature is saved into the Shapefile. Finally, we call the Destroy() method to close the output Shapefile: dstFile.Destroy() Putting all this together, and combining it with the code from the previous recipe to calculate the bounding boxes for each country in the World Borders Dataset Shapefile, we end up with the following complete program: # boundingBoxesToShapefile.py import os, os.path, shutil import osgeo.ogr import osgeo.osr # Open the source shapefile. srcFile = osgeo.ogr.Open("TM_WORLD_BORDERS-0.3.shp") srcLayer = srcFile.GetLayer(0) # Open the output shapefile. if os.path.exists("bounding-boxes"): shutil.rmtree("bounding-boxes") os.mkdir("bounding-boxes") spatialReference = osgeo.osr.SpatialReference() spatialReference.SetWellKnownGeogCS('WGS84') driver = osgeo.ogr.GetDriverByName("ESRI Shapefile") dstPath = os.path.join("bounding-boxes", "boundingBoxes.shp") dstFile = driver.CreateDataSource(dstPath) dstLayer = dstFile.CreateLayer("layer", spatialReference) fieldDef = osgeo.ogr.FieldDefn("COUNTRY", osgeo.ogr.OFTString) fieldDef.SetWidth(50) dstLayer.CreateField(fieldDef) fieldDef = osgeo.ogr.FieldDefn("CODE", osgeo.ogr.OFTString) fieldDef.SetWidth(3) dstLayer.CreateField(fieldDef) # Read the country features from the source shapefile. for i in range(srcLayer.GetFeatureCount()): feature = srcLayer.GetFeature(i) countryCode = feature.GetField("ISO3") countryName = feature.GetField("NAME") geometry = feature.GetGeometryRef() minLong,maxLong,minLat,maxLat = geometry.GetEnvelope() # Save the bounding box as a feature in the output # shapefile. linearRing = osgeo.ogr.Geometry(osgeo.ogr.wkbLinearRing) linearRing.AddPoint(minLong, minLat) linearRing.AddPoint(maxLong, minLat) linearRing.AddPoint(maxLong, maxLat) linearRing.AddPoint(minLong, maxLat) linearRing.AddPoint(minLong, minLat) polygon = osgeo.ogr.Geometry(osgeo.ogr.wkbPolygon) polygon.AddGeometry(linearRing) feature = osgeo.ogr.Feature(dstLayer.GetLayerDefn()) feature.SetGeometry(polygon) feature.SetField("COUNTRY", countryName) feature.SetField("CODE", countryCode) dstLayer.CreateFeature(feature) feature.Destroy() # All done. srcFile.Destroy() dstFile.Destroy() The only unexpected twist in this program is the use of a sub-directory called bounding-boxes to store the output Shapefile. Because a Shapefile is actually made up of multiple files on disk (a .dbf file, a .prj file, a .shp file, and a .shx file), it is easier to place these together in a sub-directory. We use the Python Standard Library module shutil to delete the previous contents of this directory, and then os.mkdir() to create it again. If you aren't storing the TM_WORLD_BORDERS-0.3.shp Shapefile in the same directory as the script itself, you will need to add the directory where the Shapefile is stored to your osgeo.ogr.Open() call. You can also store the boundingBoxes.shp Shapefile in a different directory if you prefer, by changing the path where this Shapefile is created. Running this program creates the bounding box Shapefile, which we can then draw onto a map. For example, here is the outline of Thailand along with a bounding box taken from the boundingBoxes.shp Shapefile:  

Python 3 Object Oriented Programming Harness the power of Python 3 objects Learn how to do Object Oriented Programming in Python using this step-by-step tutorial Design public interfaces using abstraction, encapsulation, and information hiding Turn your designs into working software by studying the Python syntax Raise, handle, define, and manipulate exceptions using special error objects Implement Object Oriented Programming in Python using practical examples        Basic inheritance Technically, every class we create uses inheritance. All Python classes are subclasses of the special class named object. This class provides very little in terms of data and behaviors (those behaviors it does provide are all double-underscore methods intended for internal use only), but it does allow Python to treat all objects in the same way. If we don't explicitly inherit from a different class, our classes will automatically inherit from object. However, we can openly state that our class derives from object using the following syntax: class MySubClass(object): pass This is inheritance! Since Python 3 automatically inherits from object if we don't explicitly provide a different superclass. A superclass, or parent class, is a class that is being inherited from. A subclass is a class that is inheriting from a superclass. In this case, the superclass is object, and MySubClass is the subclass. A subclass is also said to be derived from its parent class or that the subclass extends the parent. As you've probably figured out from the example, inheritance requires a minimal amount of extra syntax over a basic class definition. Simply include the name of the parent class inside a pair of parentheses after the class name, but before the colon terminating the class definition. This is all we have to do to tell Python that the new class should be derived from the given superclass. How do we apply inheritance in practice? The simplest and most obvious use of inheritance is to add functionality to an existing class. Let's start with a simple contact manager that tracks the name and e-mail address of several people. The contact class is responsible for maintaining a list of all contacts in a class variable, and for initializing the name and address, in this simple class: class Contact: all_contacts = [] def __init__(self, name, email): self.name = name self.email = email Contact.all_contacts.append(self) This example introduces us to class variables. The all_contacts list, because it is part of the class definition, is actually shared by all instances of this class. This means that there is only one Contact.all_contacts list, and if we call self.all_contacts on any one object, it will refer to that single list. The code in the initializer ensures that whenever we create a new contact, the list will automatically have the new object added. Be careful with this syntax, for if you ever set the variable using self.all_contacts, you will actually be creating a new instance variable on the object; the class variable will still be unchanged and accessible as Contact.all_contacts. This is a very simple class that allows us to track a couple pieces of data about our contacts. But what if some of our contacts are also suppliers that we need to order supplies from? We could add an order method to the Contact class, but that would allow people to accidentally order things from contacts who are customers or family friends. Instead, let's create a new Supplier class that acts like a Contact, but has an additional order method: class Supplier(Contact): def order(self, order): print("If this were a real system we would send " "{} order to {}".format(order, self.name)) Now, if we test this class in our trusty interpreter, we see that all contacts, including suppliers, accept a name and e-mail address in their __init__, but only suppliers have a functional order method: >>> c = Contact("Some Body", "somebody@example.net") >>> s = Supplier("Sup Plier", "supplier@example.net") >>> print(c.name, c.email, s.name, s.email) Some Body somebody@example.net Sup Plier supplier@example.net >>> c.all_contacts [<__main__.Contact object at 0xb7375ecc>, <__main__.Supplier object at 0xb7375f8c>] >>> c.order("Ineed pliers") Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'Contact' object has no attribute 'order' >>> s.order("I need pliers") If this were a real system we would send I need pliers order to Supplier >>> So now our Supplier class can do everything a Contact can do (including adding itself to the list of all_contacts) and all the special things it needs to handle as a supplier. This is the beauty of inheritance. Extending built-ins One of the most interesting uses of this kind of inheritance is adding functionality to built-in classes. In the Contact class seen earlier, we are adding contacts to a list of all contacts. What if we also wanted to search that list by name? Well, we could add a method on the Contact class to search it, but it feels like this method actually belongs on the list itself. We can do this using inheritance: class ContactList(list): def search(self, name): '''Return all contacts that contain the search value in their name.''' matching_contacts = [] for contact in self: if name in contact.name: matching_contacts.append(contact) return matching_contacts class Contact: all_contacts = ContactList() def __init__(self, name, email): self.name = name self.email = email self.all_contacts.append(self) Instead of instantiating a normal list as our class variable, we create a new ContactList class that extends the built-in list. Then we instantiate this subclass as our all_contacts list. We can test the new search functionality as follows: >>> c1 = Contact("John A", "johna@example.net") >>> c2 = Contact("John B", "johnb@example.net") >>> c3 = Contact("Jenna C", "jennac@example.net") >>> [c.name for c in Contact.all_contacts.search('John')] ['John A', 'John B'] >>> Are you wondering how we changed the built-in syntax [] into something we can inherit from? Creating an empty list with [] is actually a shorthand for creating an empty list using list(); the two syntaxes are identical: >>> [] == list() True So, the list data type is like a class that we can extend, not unlike object. As a second example, we can extend the dict class, which is the long way of creating a dictionary (the {:} syntax). class LongNameDict(dict): def longest_key(self): longest = None for key in self: if not longest or len(key) > len(longest): longest = key return longest This is easy to test in the interactive interpreter: >>> longkeys = LongNameDict() >>> longkeys['hello'] = 1 >>> longkeys['longest yet'] = 5 >>> longkeys['hello2'] = 'world' >>> longkeys.longest_key() 'longest yet' Most built-in types can be similarly extended. Commonly extended built-ins are object, list, set, dict, file, and str. Numerical types such as int and float are also occasionally inherited from. Overriding and super So inheritance is great for adding new behavior to existing classes, but what about changing behavior? Our contact class allows only a name and an e-mail address. This may be sufficient for most contacts, but what if we want to add a phone number for our close friends? We can do this easily by just setting a phone attribute on the contact after it is constructed. But if we want to make this third variable available on initialization, we have to override __init__. Overriding is altering or replacing a method of the superclass with a new method (with the same name) in the subclass. No special syntax is needed to do this; the subclass's newly created method is automatically called instead of the superclass's method. For example: class Friend(Contact): def __init__(self, name, email, phone): self.name = name self.email = email self.phone = phone Any method can be overridden, not just __init__. Before we go on, however, we need to correct some problems in this example. Our Contact and Friend classes have duplicate code to set up the name and email properties; this can make maintenance complicated, as we have to update the code in two or more places. More alarmingly, our Friend class is neglecting to add itself to the all_contacts list we have created on the Contact class. What we really need is a way to call code on the parent class. This is what the super function does; it returns the object as an instance of the parent class, allowing us to call the parent method directly: class Friend(Contact): def __init__(self, name, email, phone): super().__init__(name, email) self.phone = phone This example first gets the instance of the parent object using super, and calls __init__ on that object, passing in the expected arguments. It then does its own initialization, namely setting the phone attribute. A super() call can be made inside any method, not just __init__. This means all methods can be modified via overriding and calls to super. The call to super can also be made at any point in the method; we don't have to make the call as the first line in the method. For example, we may need to manipulate the incoming parameters before forwarding them to the superclass.