10.12 Colormap State Change Events

The X server can report ColormapNotify events to clients wanting information about when the colormap changes and when a colormap is installed or uninstalled. The X server generates this event type whenever a client application:

• Changes the colormap member of the XSetWindowAttributes structure by calling XChangeWindowAttributes(), XFreeColormap(), or XSetWindowColormap()

• Installs or uninstalls the colormap by calling XInstallColormap() or XUninstallColormap()

To receive ColormapNotify events, set the ColormapChangeMask bit in the event-mask attribute of the window.

The structure for this event type contains:

typedef struct {
	int type;	/* ColormapNotify */
	unsigned long serial;	/* # of last request processed by server */
	Bool send_event;	/* true if this came from a SendEvent request */
	Display *display;	/* Display the event was read from */
	Window window;
	Colormap colormap;	/* colormap or None */
	Bool new;
	int state;	/* ColormapInstalled, ColormapUninstalled */
} XColormapEvent;

The window member is set to the window whose associated colormap is changed, installed, or uninstalled. For a colormap that is changed, installed, or uninstalled, the colormap member is set to the colormap associated with the window. For a colormap that is changed by a call to XFreeColormap(), the colormap member is set to None. The new member is set to indicate whether the colormap for the specified window was changed or installed or uninstalled and can be True or False. If it is True, the colormap was changed. If it is False, the colormap was installed or uninstalled. The state member is always set to indicate whether the colormap is installed or uninstalled and can be ColormapInstalled or ColormapUninstalled.

Next: Client Communication Events

---

Christophe Tronche, [email protected]