iOS将视图保存在内存中

Question

I'm creating an app that plays music and has a nice UI for the album art and progress bar. The problem is when the user leaves the player view and goes back, the player UI has to be reloaded and you see a flash while the progress bar is resized and the album art is loaded.

Is there any way to keep items in memory when you leave a controller? Similar to how you go between playlists and player view on the iPhone music app, there is no lag or delay in seeing the artwork or song progress, it's there from the beginning.

Or am I thinking about this the wrong way?

Answer 1

I am assuming you are going back and forth using a UINavigationController , if so the default behavior is that the view controller will be released when you go back, as the only strong reference to it is in the UINavigationController stack, when it is popped the reference is lost, and therefore your controller is deallocated.

If you want to avoid this, all you need to do is have any other object have a strong reference to your view controller. An easy way to do it would be whenever you initialize your controller, in that class have a strong property that holds a reference to the view controller you do not want to lose.

Hope that helps.