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Activity.OnKeyDown(Keycode, KeyEvent) Method

Definition

Called when a key was pressed down and not handled by any of the views inside of the activity.

[Android.Runtime.Register("onKeyDown", "(ILandroid/view/KeyEvent;)Z", "GetOnKeyDown_ILandroid_view_KeyEvent_Handler")]
public virtual bool OnKeyDown (Android.Views.Keycode keyCode, Android.Views.KeyEvent? e);
[<Android.Runtime.Register("onKeyDown", "(ILandroid/view/KeyEvent;)Z", "GetOnKeyDown_ILandroid_view_KeyEvent_Handler")>]
abstract member OnKeyDown : Android.Views.Keycode * Android.Views.KeyEvent -> bool
override this.OnKeyDown : Android.Views.Keycode * Android.Views.KeyEvent -> bool

Parameters

keyCode
Keycode

The value in event.getKeyCode().

e
KeyEvent

Description of the key event.

Returns

Return true to prevent this event from being propagated further, or false to indicate that you have not handled this event and it should continue to be propagated.

Implements

Attributes

Remarks

Called when a key was pressed down and not handled by any of the views inside of the activity. So, for example, key presses while the cursor is inside a TextView will not trigger the event (unless it is a navigation to another object) because TextView handles its own key presses.

If the focused view didn't want this event, this method is called.

The default implementation takes care of KeyEvent#KEYCODE_BACK by calling #onBackPressed(), though the behavior varies based on the application compatibility mode: for android.os.Build.VERSION_CODES#ECLAIR or later applications, it will set up the dispatch to call #onKeyUp where the action will be performed; for earlier applications, it will perform the action immediately in on-down, as those versions of the platform behaved.

Other additional default key handling may be performed if configured with #setDefaultKeyMode.

Java documentation for android.app.Activity.onKeyDown(int, android.view.KeyEvent).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to

See also

  • <xref:Android.App.Activity.OnKeyUp(Android.Views.Keycode%2c+Android.Views.KeyEvent)>
  • KeyEvent