WM_NCLBUTTONDBLCLK message
Posted when the user double-clicks the left mouse button while the cursor is within the nonclient area of a window. This message is posted to the window that contains the cursor. If a window has captured the mouse, this message is not posted.
A window receives this message through its WindowProc function.
#define WM_NCLBUTTONDBLCLK 0x00A3
Parameters
- wParam
-
The hit-test value returned by the DefWindowProc function as a result of processing the WM_NCHITTEST message. For a list of hit-test values, see WM_NCHITTEST.
- lParam
-
A POINTS structure that contains the x- and y-coordinates of the cursor. The coordinates are relative to the upper-left corner of the screen.
Return value
If an application processes this message, it should return zero.
Remarks
You can also use the GET_X_LPARAM and GET_Y_LPARAM macros to extract the values of the x- and y- coordinates from lParam.
xPos = GET_X_LPARAM(lParam); yPos = GET_Y_LPARAM(lParam);
By default, the DefWindowProc function tests the specified point to find out the location of the cursor and performs the appropriate action. If appropriate, DefWindowProc sends the WM_SYSCOMMAND message to the window.
A window need not have the CS_DBLCLKS style to receive WM_NCLBUTTONDBLCLK messages.
The system generates a WM_NCLBUTTONDBLCLK message when the user presses, releases, and again presses the left mouse button within the system's double-click time limit. Double-clicking the left mouse button actually generates four messages: WM_NCLBUTTONDOWN, WM_NCLBUTTONUP, WM_NCLBUTTONDBLCLK, and WM_NCLBUTTONUP again.
Requirements
|
Minimum supported client |
Windows 2000 Professional [desktop apps only] |
|---|---|
|
Minimum supported server |
Windows 2000 Server [desktop apps only] |
|
Header |
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See also
- Reference
- DefWindowProc
- GET_X_LPARAM
- GET_Y_LPARAM
- WM_NCHITTEST
- WM_NCLBUTTONDOWN
- WM_NCLBUTTONUP
- WM_SYSCOMMAND
- Conceptual
- Mouse Input
- Other Resources
- MAKEPOINTS
- POINTS