An application sends a ZGM_SETCOLUMNHEADERHEIGHT message to set the minimum height of the column header row in pixels. If iHeight is set to 0, no column headers are displayed. This also makes the grid columns unable to be resized or reordered by the user. If the value of iHeight is greater than zero, the minimum height will be automatically calculated and set to contain the tallest column header title. If iHeight is greater than the calculated height to contain the tallest column header title, the additional space is added to the top of the column headers.
If the column header height is set to a value greater than 0, the minimum height will be automatically set to 20. If the column header titles won't fit with the 20 pixel height, it will be automatically sized up to hold the title. A value that is more than that required to contain the title will be respected.
ZGM_SETCOLUMNHEADERHEIGHT wParam = (WPARAM)(int) iHeight; //minimum height in pixels to use for the column header row lParam = 0; //not used; must be zero
This message does not return a value.