UIElement.Focus Method ()
Attempts to set focus to this element.
Assembly: PresentationCore (in PresentationCore.dll)
Return ValueType: System.Boolean
true if keyboard focus and logical focus were set to this element; false if only logical focus was set to this element, or if the call to this method did not force the focus to change.
Even if an element is focusable and enabled, event handling within a specific tree, (such as for a composite control) might respond to the preview focus events by not allowing focus there, thus this method would return false.
If the related properties are not already true, when you call PreviewLostKeyboardFocus, PreviewGotKeyboardFocus (source is the new focus target), IsKeyboardFocusedChanged, IsKeyboardFocusWithinChanged, LostKeyboardFocus, GotKeyboardFocus (source is the new focus target)., one or more of the following events are raised in the following order:
In order for this call to be successful, some other element in the application needed to have focus previously.
Available since 3.0