AnimateWindow

The AnimateWindow function enables you to produce special effects when showing or hiding windows. There are three types of animation: roll, slide, and alpha-blended fade.

- hwnd
[in] Handle to the window to animate. The calling thread must own this window.

- dwTime
[in] Specifies how long it takes to play the animation, in milliseconds. Typically, an animation takes 200 milliseconds to play.

- dwFlags
[in] Specifies the type of animation. This parameter can be one or more of the following values.
AW_SLIDE
Uses slide animation. By default, roll animation is used. This flag is ignored when used with AW_CENTER.
AW_ACTIVATE
Activates the window. Do not use this value with AW_HIDE.
AW_BLEND
Uses a fade effect. This flag can be used only if hwnd is a top-level window.
AW_HIDE
Hides the window. By default, the window is shown.
AW_CENTER
Makes the window appear to collapse inward if AW_HIDE is used or expand outward if the AW_HIDE is not used.
AW_HOR_POSITIVE
Animates the window from left to right. This flag can be used with roll or slide animation. It is ignored when used with AW_CENTER or AW_BLEND.
AW_HOR_NEGATIVE
Animates the window from right to left. This flag can be used with roll or slide animation. It is ignored when used with AW_CENTER or AW_BLEND.
AW_VER_POSITIVE
Animates the window from top to bottom. This flag can be used with roll or slide animation. It is ignored when used with AW_CENTER or AW_BLEND.
AW_VER_NEGATIVE
Animates the window from bottom to top. This flag can be used with roll or slide animation. It is ignored when used with AW_CENTER or AW_BLEND.

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. The function will fail in the following situations:

The window uses the window region.
The window is already visible and you are trying to show the window.
The window is already hidden and you are trying to hide the window.
To get extended error information, call the GetLastError function.