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private static readonly Thickness _margin 
    = new Thickness(5);
private readonly ComboBox _projectsComboBox 
    = new ComboBox() { Margin = _margin };
private readonly TextBox _estimateTextBox 
    = new TextBox() 
        { IsEnabled = false, Margin = _margin };
private readonly TextBox _actualTextBox 
    = new TextBox()
        { IsEnabled = false, Margin = _margin };
private readonly Button _updateButton = new Button()
    { 
        IsEnabled = false, 
        Content = "Update",
        Margin = _margin
    };

public ProjectsView()
{
    Title = "Project";
    Width = 250;
    MinWidth = 250;
    Height = 180;
    MinHeight = 180;
 
    LoadProjects();
 
    AddControlsToWindow();
 
    _updateButton.Click += updateButton_Click;
}

<Window x:Class="RadProjectBilling.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="250" 
        mc:Ignorable="d" 
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
        xmlns:my="clr-namespace: ProjectBilling.DataAccess;assembly=ProjectBilling.DataAccess" 
        Loaded="Window_Loaded">
    <Window.Resources>
        <CollectionViewSource x:Key="projectViewSource" d:DesignSource="{d:DesignInstance my:Project, CreateList=True}" />
    </Window.Resources>
    <Grid>
        <Grid DataContext="{StaticResource projectViewSource}"
              HorizontalAlignment="Left"
              Margin="12,12,0,0" Name="grid1"
              VerticalAlignment="Top">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto" />
                <ColumnDefinition Width="Auto" />
            </Grid.ColumnDefinitions>
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto" />
            </Grid.RowDefinitions>
            <Label Content="Name:" Grid.Column="0" 
                   Grid.Row="0" HorizontalAlignment="Left" 
                   Margin="3" VerticalAlignment="Center" />
            <ComboBox DisplayMemberPath="Name" Grid.Column="1" 
                      Grid.Row="0" Height="23" 
                      HorizontalAlignment="Left" 
                      ItemsSource="{Binding}" Margin="3" 
                      Name="nameComboBox" 
                      VerticalAlignment="Center" Width="120">
                <ComboBox.ItemsPanel>
                    <ItemsPanelTemplate>
                        <VirtualizingStackPanel />
                    </ItemsPanelTemplate>
                </ComboBox.ItemsPanel>
            </ComboBox>
        </Grid>
    </Grid>
</Window>

ItemsSource="{Binding}"

private void Window_Loaded(object sender, RoutedEventArgs e)
{

    System.Windows.Data.CollectionViewSource projectViewSource 
        = ((System.Windows.Data.CollectionViewSource)
        (this.FindResource("projectViewSource"));
    // Load data by setting the 
    // CollectionViewSource.Source property:
    // projectViewSource.Source = [generic data source]
}

// projectViewSource.Source = [generic data source]

private void Window_Loaded(object sender, RoutedEventArgs e)
{

    System.Windows.Data.CollectionViewSource projectViewSource 
        = ((System.Windows.Data.CollectionViewSource)
        (this.FindResource("projectViewSource"));
    // Load data by setting the 
    // CollectionViewSource.Source property:
    projectViewSource.Source=new DataServiceStub().GetProjects(); 

}

private void UpdateButton_Click(object sender, 
    RoutedEventArgs e)
{
    Project selectedProject
        = this.nameComboBox.SelectedItem
        as Project;
    if (selectedProject != null)
    {		        selectedProject.Estimate =
            double.Parse(this.estimateTextBox.Text);
        if (!string.IsNullOrEmpty(
            this.actualTextBox.Text))
        {
            selectedProject.Actual
                = double.Parse(
                    this.actualTextBox.Text);
        }
        SetEstimateColor(selectedProject);
    }
}

private void nameComboBox_SelectionChanged(object sender, 
    SelectionChangedEventArgs e)
{
    ComboBox comboBox = sender as ComboBox;
 
    // If there is a selected item
    if (comboBox != null && comboBox.SelectedIndex > -1)
    {
         Project selectedProject
            = comboBox.SelectedItem as Project;
 
        SetEstimateColor(selectedProject);
        this.UpdateButton.IsEnabled = true;
    }
    else
    {
        this.estimateTextBox.IsEnabled = false;
        this.actualTextBox.IsEnabled = false;
        this.UpdateButton.IsEnabled = false;
    }
}
 
private void SetEstimateColor(Project selectedProject)
{
    if (selectedProject.Actual == 0)
    {
        this.estimateTextBox.Foreground
            = Brushes.Black;
    }
    else if (selectedProject.Actual
        <= selectedProject.Estimate)
    {
        this.estimateTextBox.Foreground
            = Brushes.Green;
    }
    else
    {
        this.estimateTextBox.Foreground
            = Brushes.Red;
    }
 }

<Window.Resources>
    <CollectionViewSource x:Key="projectViewSource"
            d:DesignSource="{d:DesignInstance my:Project, 
                                CreateList=True}" />
</Window.Resources>

<TextBox Grid.Column="1" Grid.Row="0" Height="23"
        HorizontalAlignment="Left" Margin="3"
        Name="actualTextBox"
        Text="{Binding Path=Actual, Mode=TwoWay, 
                ValidatesOnExceptions=true, 
                NotifyOnValidationError=true}"
        VerticalAlignment="Center" Width="120" />

using System;
using System.Collections.Generic;
using System.Linq;
using ProjectBilling.DataAccess;

namespace ProjectBilling.Business.MVC
{
    public interface IProjectsModel
    {
        IEnumerable<Project> Projects { get; set; }
        event EventHandler<ProjectEventArgs> ProjectUpdated;
        void UpdateProject(Project project);
    }

    public class ProjectsModel : IProjectsModel
    {
        public IEnumerable<Project> Projects { get; set; }

        public event EventHandler<ProjectEventArgs>
            ProjectUpdated = delegate { };

        public ProjectsModel()
        {
            Projects = new DataServiceStub().GetProjects();
        }

        private void RaiseProjectUpdated(Project project)
        {
            ProjectUpdated(this, 
                new ProjectEventArgs(project));
        }

        public void UpdateProject(Project project)
        {
            Project selectedProject
                = Projects.Where(p => p.ID == project.ID)
                      .FirstOrDefault() as Project;
            selectedProject.Name = project.Name;
            selectedProject.Estimate = project.Estimate;
            selectedProject.Actual = project.Actual;
            RaiseProjectUpdated(selectedProject);
        }
    }

    public class ProjectEventArgs : EventArgs
    {

        public Project Project { get; set; }

        public ProjectEventArgs(Project project)
        {
            Project = project;
        }
    }
}

    public interface IProjectsModel
    {
        IEnumerable<Project> Projects { get; set; }
        event EventHandler<ProjectEventArgs> ProjectUpdated;
        void UpdateProject(Project project);
    }

using System;
using ProjectBilling.Business.MVC;
using ProjectBilling.DataAccess;
using System.Windows;

namespace ProjectBilling.UI.MVC
{
    public interface IProjectsController
    {
        void ShowProjectsView(Window owner);
        void Update(Project project);
    }

    public class ProjectsController : IProjectsController
    {
        private readonly IProjectsModel _model;

        public ProjectsController(IProjectsModel projectModel)
        {
            if (projectModel == null)
                throw new ArgumentNullException(
                    "projectModel");
            _model = projectModel;
        }

        public void ShowProjectsView(Window owner)
        {
            ProjectsView view 
                = new ProjectsView(this, _model);
            view.Owner = owner;
            view.Show();
        }

        public void Update(Project project)
        {
            _model.UpdateProject(project);
        }
    }
}

<Window x:Class="ProjectBilling.UI.MVC.ProjectsView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Projects" MinHeight="180" Height="180"
        MinWidth="250" Width="250" Padding="5"
        FocusManager.FocusedElement
            ="{Binding ElementName=ProjectsComboBox}">
    <UniformGrid Columns="2">
        <Label Content="Project:" />
        <ComboBox Name="ProjectsComboBox" Margin="5"
                SelectionChanged
                    ="ProjectsComboBox_SelectionChanged" />
        <Label Content="Estimated Cost:" />
        <TextBox Name="EstimatedTextBox" Margin="5" 
                 IsEnabled="False" />
        <Label Content="Actual Cost:" />
        <TextBox Name="ActualTextBox" Margin="5" 
                 IsEnabled="False" />
        <Button Name="UpdateButton" Content="Update"
                Margin="5" IsEnabled="False" 
                Click="UpdateButton_Click" />
    </UniformGrid>
</Window>

using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using ProjectBilling.Business.MVC;
using ProjectBilling.DataAccess;

namespace ProjectBilling.UI.MVC
{
    public partial class ProjectsView : Window
    {
        private readonly IProjectsModel _model;
        private readonly IProjectsController _controller 
            = null;
        private const int NONE_SELECTED = -1;
    }
}

<Button Content="GC Collect"
        Name="GCCollectButton" Margin="5"
        Click="GCCollectButton_Click" />

private void GCCollectButton_Click(object sender, 
    RoutedEventArgs e)
{
    GC.Collect();
    GC.WaitForPendingFinalizers();
    GC.Collect();
}

~ProjectsView()
{
    MessageBox.Show("ProjectsView collected");
}

protected override void OnClosed(EventArgs e)
{
    base.OnClosed(e);
    _model.ProjectUpdated -= model_ProjectUpdated;
}

using System;
using System.Collections.Generic;
using System.Linq;
using ProjectBilling.DataAccess;

namespace ProjectBilling.Business
{
    public class ProjectEventArgs : EventArgs
    {
        public Project Project { get; set; }
        public ProjectEventArgs(Project project)
        {
            Project = project;
        }
    }

    public interface IProjectsModel
    {
        void UpdateProject(Project project);
        IEnumerable<Project> GetProjects();
        Project GetProject(int Id);
        event EventHandler<ProjectEventArgs> ProjectUpdated;
    }

    public class ProjectsModel : IProjectsModel
    {

        private IEnumerable<Project> projects = null;

        public event EventHandler<ProjectEventArgs> 
            ProjectUpdated = delegate { };

        public ProjectsModel()
        {
            projects = new DataServiceStub().GetProjects();
        }

        public void UpdateProject(Project project)
        {
            ProjectUpdated(this, 
                new ProjectEventArgs(project));
        }

        public IEnumerable<Project> GetProjects()
        {
            return projects;
        }


        public Project GetProject(int Id)
        {
            return projects.Where(p => p.ID == Id)
                .First() as Project;
        }
    }
}

<Window x:Class="ProjectBilling.UI.MVP.ProjectsView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Projects" MinHeight="180" Height="180"
        MinWidth="250" Width="250" Padding="5"
        FocusManager.FocusedElement
            ="{Binding ElementName=ProjectsComboBox}">
    <UniformGrid Columns="2">
        <Label Content="Project:" />
        <ComboBox Name="ProjectsComboBox" Margin="5"
                SelectionChanged
                    ="ProjectsComboBox_SelectionChanged" />
        <Label Content="Estimated Cost:" />
        <TextBox Name="EstimatedTextBox" Margin="5" 
                 IsEnabled="False" />
        <Label Content="Actual Cost:" />
        <TextBox Name="ActualTextBox" Margin="5" 
                 IsEnabled="False" />
        <Button Name="UpdateButton" Content="Update"
                Margin="5" IsEnabled="False" 
                Click="UpdateButton_Click" />
    </UniformGrid>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using ProjectBilling.Business;
using ProjectBilling.DataAccess;

namespace ProjectBilling.UI.MVP
{
    public interface IProjectsView
    {
        int NONE_SELECTED { get; }
        int SelectedProjectId { get; }
        void UpdateProject(Project project);
        void LoadProjects(IEnumerable<Project> projects);
        void UpdateDetails(Project project);
        void EnableControls(bool isEnabled);
        void SetEstimatedColor(Color? color);
        event EventHandler<ProjectEventArgs> ProjectUpdated;
        event EventHandler<ProjectEventArgs> DetailsUpdated;
        event EventHandler SelectionChanged;
    }

    /// <summary>
    /// Interaction logic for ProjectsView.xaml
    /// </summary>
    public partial class ProjectsView : Window, IProjectsView
    {

        public int NONE_SELECTED { get { return -1; } }
            public event EventHandler<ProjectEventArgs> 
            ProjectUpdated = delegate { };
        public int SelectedProjectId { get; private set; }

        public event EventHandler SelectionChanged
            = delegate { };
        public event EventHandler<ProjectEventArgs>
            DetailsUpdated = delegate { };

        public ProjectsView()
        {
            InitializeComponent();
            SelectedProjectId = NONE_SELECTED;
        }

    }
}

using System;
using System.Windows.Media;
using ProjectBilling.Business;
using ProjectBilling.DataAccess;

namespace ProjectBilling.UI.MVP
{
    public class ProjectsPresenter
    {
        private readonly IProjectsView _view = null;
        private readonly IProjectsModel _model = null;

        public ProjectsPresenter(IProjectsView projectsView, 
            IProjectsModel projectsModel)
        {
            _view = projectsView;
            _view.ProjectUpdated += view_ProjectUpdated;
            _view.SelectionChanged 
                += view_SelectionChanged;
            _view.DetailsUpdated += view_DetailsUpdated;
            _model = projectsModel;
            _model.ProjectUpdated += model_ProjectUpdated;
            _view.LoadProjects(
                _model.GetProjects());
        }
 
    }
}

this.view.LoadProjects(
    this.model.GetProjects());

<Window x:Class="ProjectBilling.UI.MVP.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Shell" Height="150" Width="200"
        MinHeight="150" MinWidth="200"
        FocusManager.FocusedElement
            ="{Binding ElementName=ShowProjectsButton}">
    <StackPanel>
        <Button Content="Show Projects"
                Name="ShowProjectsButton" Margin="5"
                Click="ShowProjectsButton_Click" />
    </StackPanel>
</Window>

using System.Windows;
using ProjectBilling.Business;

namespace ProjectBilling.UI.MVP
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        private IProjectsModel _model = null;

        public MainWindow()
        {
            InitializeComponent();
            _model = new ProjectsModel();
        }

        private void ShowProjectsButton_Click(object sender,
            RoutedEventArgs e)
        {
            ProjectsView view = new ProjectsView();
            ProjectsPresenter presenter 
                = new ProjectsPresenter(view, _model);
            view.Owner = this;
            view.Show();
        }
    }
}