I've written custom control which allows the user to change the currentPlaybackTime of a MPMoviePlayerController by clicking or dragging on a custom UIButton that displays an image of some musical notation. The code uses the x position of the touch event to update currentPlaybackTime and it all works fine. I also have a CALayer (a vertical red line) that shows the user where they have touched on the control.
What I'd like to do now is have the red line's (CALayer object) position update if the user changes the currentPlaybackTime property of the movie player using the scrubber (slider) control.
Obviously currentPlaybackTime is always updating as the movie plays, but is there a way to detect if the user interferes with this by skipping forward or backwards?
Many thanks.
You could use Key-Value-Observing to track changes of currentPlaybackTime in your MPMoviePlayerController, but that might generate a lot of events and thus negatively affect your performance. Maybe you can also use KVO with the playbackState property of your MPMoviePlayerController, I believe it changes when the user starts seeking.
Another alternative is that you just setup a repeating timer that updates quite frequently, and everytime it fires you check the new value of currentPlaybackTime. But that might look choppy and it could also affect performance.