typedef SInt16 DragTrackingMessage;
enum {
    kDragTrackingEnterHandler = 1,
    kDragTrackingEnterWindow = 2,
    kDragTrackingInWindow = 3,
    kDragTrackingLeaveWindow = 4,
    kDragTrackingLeaveHandler = 5
};

Constant descriptions

kDragTrackingEnterHandler

Your tracking handler receives this message when the focus of a drag enters a window that is handled by your tracking handler. If the user moves the drag directly to another window that is handled by the same tracking handler, a second kDragTrackingEnterHandler message is not received. Your tracking handler only receives this message when the drag enters the domain of your function after leaving another.

kDragTrackingEnterWindow

Your tracking handler receives this message when a drag enters any window that is handled by your tracking handler. This message is sent to your tracking handler for each window that the drag may enter. Your tracking handler will always receive this message within a pair of kDragTrackingEnterHandler and kDragTrackingLeaveHandler messages.

kDragTrackingInWindow

Your tracking handler receives this message as the user is dragging within a window handled by your tracking handler. You can use this message to track the dragging process through your window. Your tracking handler will always receive this message within a pair of kDragTrackingEnterWindow and kDragTrackingLeaveWindow messages.Your tracking handler would typically draw the majority of your window highlighting and track objects in your window when you receive this message from the Drag Manager.

kDragTrackingLeaveWindow

Your tracking handler receives this message when a drag leaves any window that is handled by your tracking handler. You are guaranteed to receive this message after receiving a corresponding kDragTrackingEnterWindow message. Your tracking handler will always receive this message within a pair of kDragTrackingEnterHandler and kDragTrackingLeaveHandler messages.

kDragTrackingLeaveHandler

Your tracking handler receives this message when the focus of a drag enters a window that is not handled by your tracking handler. Your tracking handler is guaranteed to receive this message after receiving a corresponding kDragTrackingEnterHandler message.

© 2001 Apple Computer, Inc. (Last Updated July 17, 2001)