The WM_ACTIVATE message is sent to both the window being activated and the window being deactivated. If the windows use the same input queue, the message is sent synchronously, first to the window procedure of the top-level window being deactivated, then to the window procedure of the top-level window being activated. If the windows use different input queues, the message is sent asynchronously, so the window is activated immediately.
WM_ACTIVATE
fActive = LOWORD(wParam); // activation flag
fMinimized = (BOOL) HIWORD(wParam); // minimized flag
hwndPrevious = (HWND) lParam; // window handle
Value | Meaning |
---|---|
WA_ACTIVE | Activated by some method other than a mouse click (for example, by a call to the SetActiveWindow function or by use of the keyboard interface to select the window). |
WA_CLICKACTIVE | Activated by a mouse click. |
WA_INACTIVE | Deactivated. |
If an application processes this message, it should return zero.
If the window is being activated and is not minimized, the DefWindowProc function sets the keyboard focus to the window.
If the window is activated by a mouse click, it also receives a WM_MOUSEACTIVATE message.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
Keyboard Input Overview, Keyboard Input Messages, DefWindowProc, SetActiveWindow, WM_MOUSEACTIVATE, WM_NCACTIVATE