![]() This allows for keyboard focus to be changed between multiple focus scopes but ensures that the focused element in the focus scope regains keyboard focus when focus returns to the focus scope. When keyboard focus returns to the focus scope, the focused element will obtain keyboard focus. When keyboard focus leaves a focus scope, the focused element will lose keyboard focus but will retain logical focus. ![]() A focus scope is an element that keeps track of the FocusedElement within its scope. Logical focus refers to the FocusManager.FocusedElement in a focus scope. A Dispatcher callback can also be used by calling Invoke or BeginInvoke. The recommended place to set initial focus is in the Loaded event handler. When setting initial focus at application startup, the element to receive focus must be in the visual tree of the initial window loaded by the application, and the element must have Focusable and IsVisible set to true. The IsKeyboardFocusWithin property on the base element classes gets a value indicating whether the element or any one of its visual child elements has keyboard focus. The IsKeyboardFocused property on the base element classes gets a value indicating whether the element has keyboard focus. ' Sets keyboard focus on the first Button in the sample. Private Sub OnLoaded(ByVal sender As Object, ByVal e As RoutedEventArgs) Sets keyboard focus on the first Button in the sample. private void OnLoaded(object sender, RoutedEventArgs e) The following example uses the Focus method to set keyboard focus on a Button. ![]() The returned element is the element that has keyboard focus, which might be a different element than requested if either the old or new focus object block the request. The Focus method attempts to give the specified element keyboard focus. Keyboard focus can also be obtained programmatically by using the Focus method on the Keyboard class. Keyboard focus can be obtained through user interaction with the UI, such as tabbing to an element or clicking the mouse on certain elements. Some classes, such as the Panel base class, have Focusable set to false by default therefore, you must set Focusable to true if you want such an element to be able to obtain keyboard focus. In order for an element to obtain keyboard focus, the Focusable and the IsVisible properties on the base elements must be set to true. The static property FocusedElement on the Keyboard class gets the element that currently has keyboard focus. In WPF, the element that has keyboard focus will have IsKeyboardFocused set to true. There can be only one element on the whole desktop that has keyboard focus. Keyboard focus refers to the element that is currently receiving keyboard input. This is apparent when you use the Keyboard class to set the element that has keyboard focus, for it also sets logical focus on the element. An element that has keyboard focus will also have logical focus, but an element that has logical focus does not necessarily have keyboard focus. The Keyboard class is concerned primarily with keyboard focus and the FocusManager is concerned primarily with logical focus, but this is not an absolute distinction. For more information about the base elements, see the Base Elements Overview. The major classes that participate in focus management are the Keyboard class, the FocusManager class, and the base element classes, such as UIElement and ContentElement. ![]() Understanding the difference in these concepts is important for creating complex applications that have multiple regions where focus can be obtained. These concepts are discussed in detail in this overview. Keyboard focus refers to the element that receives keyboard input and logical focus refers to the element in a focus scope that has focus. In WPF there are two main concepts that pertain to focus: keyboard focus and logical focus. ![]()
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