Occurs when a window becomes the foreground window.
Assembly: PresentationFramework (in PresentationFramework.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
A window is activated (becomes the foreground window) when:
The window is first opened.
A user switches to a window by selecting it with the mouse, pressing ALT+TAB, or from Task Manager.
A user clicks the window's taskbar button.
Windows that need to detect when they become activate can handle the event.
After a window is first activated, it may be deactivated and reactivated many times during its lifetime. If an application's behavior or state depends on its activation state, it can inspect IsActive to determine which activation state it's in.
An application can also be Activated.
Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.