A title-bar control window sends messages to its owner (the frame window) when the control receives user input. Following are the messages that the title-bar control processes. Each message is described in terms of how the title-bar control responds to that message.
┌────────────────────┬────────────────────────────────────────┐ │Message │Description │ ├────────────────────┼────────────────────────────────────────┤ │TBM_QUERYHILITE │Returns the highlighted state of the │ │ │title bar. │ ├────────────────────┼────────────────────────────────────────┤ │TBM_SETHILITE │Sets the highlighted state of the title │ │ │bar, repainting the title bar if the │ │ │state is changing. │ ├────────────────────┼────────────────────────────────────────┤ │WM_BUTTON1DBLCLK │Restores the title bar if the owner │ │ │window is minimized or maximized. If │ │ │the window is neither minimized nor │ │ │maximized, this message maximizes the │ │ │window. │ ├────────────────────┼────────────────────────────────────────┤ │WM_BUTTON1DOWN │Sends the WM_TRACKFRAME message to the │ │ │owner window to start the tracking │ │ │operation for the frame window. │ ├────────────────────┼────────────────────────────────────────┤ │WM_CREATE │Sets the text for the title bar. Returns│ │ │FALSE if the text is already set. │ ├────────────────────┼────────────────────────────────────────┤ │WM_DESTROY │Frees the window text for the title bar.│ ├────────────────────┼────────────────────────────────────────┤ │WM_HITTEST │Always returns HT_NORMAL, so that the │ │ │title bar does not beep when it is │ │ │disabled. (It is disabled when the frame│ │ │window is maximized.) │ ├────────────────────┼────────────────────────────────────────┤ │WM_PAINT │Draws the title bar. │ ├────────────────────┼────────────────────────────────────────┤ │WM_QUERYDLGCODE │Returns the predefined constant │ │ │DLGC_STATIC. The user cannot use the Tab│ │ │key to move to the title bar in a dialog│ │ │window. │ ├────────────────────┼────────────────────────────────────────┤ │WM_QUERYWINDOWPARAMS│Returns the requested window parameters.│ ├────────────────────┼────────────────────────────────────────┤ │WM_SETWINDOWPARAMS │Sets the specified window parameters. │ ├────────────────────┼────────────────────────────────────────┤ │WM_WINDOWPOSCHANGED │Returns FALSE. Processes this message to│ │ │prevent the WinDefWindowProc function │ │ │from sending the size and show messages.│ └────────────────────┴────────────────────────────────────────┘