HDM_LAYOUT message

Retrieves information used to set the size and position of the header control within the target rectangle of the parent window. You can send this message explicitly or use the Header_Layout macro.

Parameters

wParam

Must be zero.

lParam

A pointer to an HDLAYOUT structure. The prc member specifies the coordinates of a rectangle, and the pwpos member receives the size and position for the header control within the rectangle.

Return value

Returns TRUE if successful, or FALSE otherwise.

Remarks

The pwpos member of the lParam structure receives size and position values appropriate for positioning the control along the top of the specified rectangle. The height value is the sum of the heights of the control's horizontal borders and the average height of characters in the font currently selected into the control's device context.

To use HDM_LAYOUT to set the initial size and position of a header control, set the initial visibility state of the control so that it is hidden. After sending HDM_LAYOUT to retrieve the size and position values, use the SetWindowPos function to set the new size, position, and visibility state.

Requirements

Requirement Value
Minimum supported client
Windows Vista [desktop apps only]
Minimum supported server
Windows Server 2003 [desktop apps only]
Header
Commctrl.h