Window Class

Reference

Definition

Namespace:: Microsoft.UI.Xaml

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Edit

Represents the window of the current Application.

/// [Microsoft.UI.Xaml.Markup.ContentProperty(Name="Content")]
/// [Windows.Foundation.Metadata.ContractVersion(Microsoft.UI.Xaml.WinUIContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
class Window

[Microsoft.UI.Xaml.Markup.ContentProperty(Name="Content")]
[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.UI.Xaml.WinUIContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
public class Window

Public Class Window

Inheritance: Object IInspectable Window

Attributes: ContentPropertyAttribute ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

Examples

OnLaunched

The following code example shows the OnLaunched method override generated for the WinUI in Desktop template in Microsoft Visual Studio. This code demonstrates typical usage of the Activate method on Window.

protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
{
    m_window = new MainWindow();
    m_window.Activate();
}

private Window m_window;

Create a new Window

In your apps you can create each Window explicitly. Creating more than one Window requires the 1.0.1 update to WindowsAppSDK, and is limited to a single thread.

var window = new Window();
window.Content = new TextBlock() { Text = "Hello" };
window.Activate();

You can also define a new Window in markup:

<Window 
    x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <TextBlock>Hello</TextBlock>
</Window>

with corresponding code-behind:

public partial class MainWindow : Window
{
  public MainWindow()
  {
    InitializeComponent();
  }
}

...
var window = new MainWindow();
window.Activate();

Remarks

You can create more than one Window per thread in your apps. See Create a new Window in Examples.

Window implements IWindowNative to enable interop through the Window's HWND (WindowHandle).

Typically, Window is used to set a UIElement to the Content that represents the app UI. This is usually done as part of app activation (for example in the OnLaunched override) and allows you to change the window content throughout the lifetime of the window.

Ensure you call Activate on any Window used on initial activation. If you use the default app templates from Microsoft Visual Studio, Window.Activate is included in the App.xaml code-behind file.

Constructors

Window()

Initializes a new instance of the Window class.

Properties

AppWindow	Gets the `AppWindow` associated with this XAML `Window`.
Bounds	Gets a Rect value containing the height and width of the application window in units of effective (view) pixels.
Compositor	Gets the Compositor for this window.
Content	Gets or sets the visual root of an application window.
CoreWindow	Desktop apps always return `null` for this property.
Current	Desktop apps always return `null` for this property.
Dispatcher	Always returns `null` in a Windows App SDK app. Note `Window.Dispatcher` may be altered or unavailable in future releases. Use Window.DispatcherQueue instead.
DispatcherQueue	Gets the `DispatcherQueue` object for the window.
ExtendsContentIntoTitleBar	Gets or sets a value that specifies whether the default title bar of the window should be hidden to create space for app content.
SystemBackdrop	Gets or sets the system backdrop to apply to this `Window`. The backdrop is rendered behind the `Window` content.
Title	Gets or sets a string used for the window title.
Visible	Gets a value that reports whether the window is visible.

Methods

Activate()	Attempts to activate the application window by bringing it to the foreground and setting the input focus to it.
Close()	Closes the application window.
SetTitleBar(UIElement)	Enables title bar behavior on a XAML element when `ExtendsContentIntoTitleBar` is `true`.

Events

Activated	Occurs when the window has successfully been activated.
Closed	Occurs when the window has closed.
SizeChanged	Occurs when the app window has first rendered or has changed its rendering size.
VisibilityChanged	Occurs when the value of the Visible property changes.

Applies to