有关WM_WINDOWPOSCHANGING消息的问题

[chw_csdn_chw]

我在研究WM_WINDOWPOSCHANGING消息时在delphi 6.0 的帮助中找到这样一段注解：
The WM_WINDOWPOSCHANGING message is sent to a window whose size, position, or place in the Z order is about to change as a result of a call to the SetWindowPos function or another window-management function.

WM_WINDOWPOSCHANGING
lpwp = (LPWINDOWPOS) lParam; // points to size and position data

Parameters

lpwp
Value of lParam. Points to a WINDOWPOS structure that contains information about the window's new size and position.

请问，LPWINDOWPOS类型在哪个单元中定义的
要在程序中使用LPWINDOWPOS,需要use 哪个单元？

[hatedeadlock]

LPWINDOWPOS Points to a WINDOWPOS structure

The WINDOWPOS structure contains information about the size and position of a window.

typedef struct _WINDOWPOS { // wp
HWND hwnd;
HWND hwndInsertAfter;
int x;
int y;
int cx;
int cy;
UINT flags;
} WINDOWPOS;


Members

hwnd

Identifies the window.

hwndInsertAfter

Specifies the position of the window in Z order (front-to-back position). This member can be the handle of the window behind which this window is placed, or can be one of the special values listed with the SetWindowPos function.

x

Specifies the position of the left edge of the window.

y

Specifies the position of the top edge of the window.

cx

Specifies the window width, in pixels.

cy

Specifies the window height, in pixels.

flags

Specifies the window position. This member can be one of the following values:

Value Meaning
SWP_DRAWFRAME Draws a frame (defined in the window's class description) around the window.
SWP_FRAMECHANGED Sends a WM_NCCALCSIZE message to the window, even if the window's size is not being changed. If this flag is not specified, WM_NCCALCSIZE is sent only when the window's size is being changed.
SWP_HIDEWINDOW Hides the window.
SWP_NOACTIVATE Does not activate the window. If this flag is not set, the window is activated and moved to the top of either the topmost or non-topmost group (depending on the setting of the hWndInsertAfter parameter).
SWP_NOCOPYBITS Discards the entire contents of the client area. If this flag is not specified, the valid contents of the client area are saved and copied back into the client area after the window is sized or repositioned.
SWP_NOMOVE Retains the current position (ignores the X and Y parameters).
SWP_NOOWNERZORDER Does not change the owner window's position in the Z order.
SWP_NOREDRAW Does not redraw changes. If this flag is set, no repainting of any kind occurs. This applies to the client area, the nonclient area (including the title bar and scroll bars), and any part of the parent window uncovered as a result of the window being moved. When this flag is set, the application must explicitly invalidate or redraw any parts of the window and parent window that need redrawing.
SWP_NOREPOSITION Same as the SWP_NOOWNERZORDER flag.
SWP_NOSENDCHANGING Prevents the window from receiving the WM_WINDOWPOSCHANGING message.
SWP_NOSIZE Retains the current size (ignores the cx and cy parameters).
SWP_NOZORDER Retains the current Z order (ignores the hWndInsertAfter parameter).
SWP_SHOWWINDOW Displays the window.

[FrameSniper]

楼上的朋友的答复不知道要说明什么？

应该是在Windows单元中有相关说明，如果你需要使用这个消息的参数，可以直接使用LParams，而不是这个具体的结构！

[pankun]

你先定义一个WindowPos类型的变量(声明于Windows单元).
例如
WinPos: WindowPos;
再用@WindowPos作LParam参数就可以了.

[hatedeadlock]

LPWINDOWPOS Points to a WINDOWPOS structure
var w:windowpos
@w就是你要的参数了吗