QuickTime Kit Programming Guide - filibeto.org

C H A P T E R 4
Adding New Capabilities to the
QTKitPlayer Application
In this chapter, you’ll extend the QTKitPlayer application beyond what you have constructed in the
previous chapter. You’ll add an NSDrawer object to the QTMovieView window, which toggles open
and close with the click of a mouse. The drawer will also have new, enhanced functionality, including
the capability of displaying a movie’s current time and duration, its normal and current size, and its
source.
Notably, as you work through the steps outlined in this chapter and add new chunks of code to your
Xcode project, you’ll implement a callback mechanism from the QuickTime C API.
When you’ve completed your Xcode project, you’ll be able to choose File > New in your extended
QTKitPlayer and an untitled QuickTime movie with a black screen will open for you. If you click the
button in the middle of the frame to the right, as shown in Figure 4-1, a Cocoa drawer pops open.
Figure 4-1 An untitled QuickTime movie with an open Cocoa drawer
The button in the movie frame lets you toggle the drawer open and closed, with fields of useful
information about the movie being displayed. The information displayed, however, is not static.
By implementing a callback mechanism from the QuickTime C API, your QTKitPlayer will be able
to synchronize the current time to the playback of the movie itself.
When a QuickTime movie plays, for example, the current time field is updated synchronously with
the movie, as illustrated in Figure 4-2.
2005-11-09 | © 2004, 2005 Apple Computer, Inc. All Rights Reserved.
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