54.2 Designing the User Interface

The user interface for the MainActivity class is very simple, consisting solely of a ConstraintLayout and a Button object. Within the Project tool window, locate the app -> res -> layout -> activity_main.xml file and double-click on it to load it into the Layout Editor tool.

Delete the default TextView and, with Autoconnect mode enabled, position a Button widget so that it is centered within the layout. Note that the text on the button (“Show Web Page”) has been extracted to a string resource named show_web_page.

Figure 54-1

With the Button selected use the Attributes tool window to configure the onClick property to call a method named showWebPage.