DMEnableDisplay

DMEnableDisplay
Header:	Displays.h		Carbon status:	Supported

Reactivates a display made inactive with the function DMDisableDisplay. You should generally never need to use this function.

OSErr DMEnableDisplay (
    GDHandle enableDevice, 
    Handle displayState
);

Parameter descriptions

enableDevice: A handle to the GDevice structure for the video device whose display you wish to make active.
displayState: If your application called DMBeginConfigureDisplays, you must pass the displayState handle obtained. Otherwise pass NULL in this parameter.

function result: A result code.

DISCUSSION

The function DMEnableDisplay reactivates the specified video device by adding its display area to the desktop.

If you add a display with the function DMAddDisplay and there are no active displays, the Display Manager will enable the added display.

SPECIAL CONSIDERATIONS

Because this function may move or purge memory blocks or access handles, you cannot call it at interrupt time.

Applications generally never need to use this function. In case you find a compelling need to change the user’s display configuration, this function is described here for completeness. Note that if your application uses Display Manager functions to change the display configuration of the user’s video devices, your application should make these changes only with the consent of the user. If your application must have a specific pixel depth, for example, it should display a dialog box that offers the user a choice between changing to that depth or canceling display of the image.

AVAILABILITY

Supported in Carbon. Available in Carbon 1.0.2 and later when running Mac OS 8.1 or later.