Technical Q&As
QTMCC 02 - Setting the option button in the ICM dialog (1-June-95)
Q We need to provide more options to the user than the normal Image Compression
Dialog contains. Inside Macintosh suggests that it's possible to provide
an extra Options button in the dialog, but this seems to be a function of the
application, not the codec. Is there some flag the codec provides that tells
applications to display the button?
A If your codec component has an exported function named CDRequestSettings, then
the Standard Compression dialog is smart enough to put up the specific button.
In other words, the QuickTime code checks out the codec component and adds the
button (if available), handles hit testing of the button, and calls
CDRequestSettings. You will get the rect of the displayed Rect with the
coordinates if you want to display your dialog inside the other one. In many
cases, it makes sense to provide a filterProc as well for processing of update
events (I guess one exception is a totally modal dialog box).
To do a quick test, put a DebugStr inside your CDRequestSettings, and check out
if the Standard Dialog displays the button, and if hit your function is called.
If this does not happen, the CDRequestSettings function is not globally
exported from the function.
See also: QuickTime Technote QT4.
Technical Q&As
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