Resizing in VB.NET

Generate QR Code 2d barcode in VB.NET Resizing

While all of the other functions are considered pretty essential to window management, resizing is completely optional. Some applications don t allow resizing by the end user. But, since Silverlight makes it so simple to rescale or resize elements when the window is resized, this decision should be made only for aesthetic reasons and not for lack of time to implement. To support resizing, DragMove has a sister function named DragResize. The DragResize move works much like DragMove, except it takes in a parameter that allows you to specify exactly where in the window the user is resizing. Listing 5.6 builds on the previous examples and shows how to use DragResize with a typical corner resize. Keep in mind that you can specify any edge by using multiple resize elements and calling DragResize with the appropriate parameter.

Listing 5.6 Implementing resize using an element in the bottom right corner XAML:

<Grid x:Name="ResizeArea" Background="Blue" Height="30" Width="30" VerticalAlignment="Bottom" HorizontalAlignment="Right" /> <StackPanel Orientation="Horizontal" ...

public MainPage() { InitializeComponent(); ... ResizeArea.MouseLeftButtonDown += new MouseButtonEventHandler(ResizeArea_MouseLeftButtonDown); } void ResizeArea_MouseLeftButtonDown(object sender, MouseButtonEventArgs e) { Application.Current.MainWindow.DragResize( WindowResizeEdge.BottomRight); }

Controlling the main window when running in the out-of-browser mode is an essential addition to the Silverlight platform. It enables you to write applications that really look and feel like native operating system apps if you want them to. It also enables you to create truly branded experiences that extend all the way to the edges of the window. Silverlight provides a number of ways you can control the window, from simply setting its size and position, to floating it above other windows, all the way to using custom chrome. Silverlight also provides functions and properties to make window manipulation easier when you implement your own chrome.

Sometimes what you want isn t actually a host window in an out-of-browser application but rather just the ability to take your in- or out-of-browser application to full screen, overlaying even the operating system shell UI elements. Yes, Silverlight can do that too.

Most browsers support the ability to run in the full-screen mode, typically by pressing F11 or selecting the Full Screen option from the Tools menu equivalent. Though this mode is nice, the amount of real estate given over to the application isn t consistent between browser versions. For example, the older versions of Internet Explorer kept the status bar and some other elements on the screen. Internet Explorer 8+ and Google Chrome both allow the browser to take over the entire screen, without any additional, ahem, chrome visible. Firefox (as of this writing) shows a small gray bar at the top used as a hotspot for the toolbar. All of these also require the user to navigate a browser-specific menu or press a browser-specific (but currently identical) hotkey. The other problem is that there is no way to handle this when running in the out-of-browser mode. Silverlight also supports its own full-screen mode, available both in and out of the browser. The experience is the same across browsers and the mode may be invoked via a button you provide in the Silverlight application. This allows you to keep the user s focus inside the application (no Best viewed in full-screen mode, accessed by F11 prompts) and enable the functionality in a way that s consistent with your application s experience. In a sandboxed application in the browser or a non-elevated application out of the browser, Silverlight s full-screen support limits the types of keyboard entry just to those typically used in media players and games (arrow keys, page navigation keys, and so on). The reason for this is to prevent taking over the entire screen and spoofing an operating system login experience, thereby capturing the user s password and perhaps sending it off to some scary site to be used to gain access to your private information, like your tax returns for the past five years and that passwords.txt file you thought no one would notice. There are some significant differences between the capabilities enabled by full screen in the partial-trust mode and full screen in the elevated-trust mode. Let s tackle them separately.