iPhone app Launch Image with different backgrounds

This question is similar to this one. M开发者_运维知识库y iPhone app allows the user to select the background image to use for the main screen. Therefore, depending on the background image selected by the user, the Launch Image screenshot (of the main screen) will likely display the wrong background image. When the main screen is finally loaded and the Launch Image is removed, it will be quite ugly for the background image to change suddenly to what the user has selected.

Does anyone have any suggestions on how to deal with this? Should I use some kind of splash screen (I thought I read in Apple's HIG that this was not allowed)? Or maybe I should somehow "transition" the user's selected background image into the view after the Launch Image is dismissed and the main screen is visible. Any thoughts?

If you really want to show a 'Splash' Image what you could do is forget about dynamically changing Default.png and use a simulated splash screen effect (simply a UIView or UIImageView covering the entire screen) which disappears after a number of seconds. What you need to ensure is you do the minimal amount of work to show the simulated splash screen and get it on the screen as fast as possible and then do any other computations later on whilst your image is shown.

There is no way you could change the actual Default.png without having the risk of your app being rejected by Apple.

Depending on how long your application takes to launch, you can use a black image as default.png. A "splash screen" isn't recommended but if there is no generic image possible and your app takes a significant amount of time to launch, it would be a better approach for the user's perspective as they would at least know that the application is launching.

Also remember that default.png is only shown when your app first launches, not when it resumes from multitasking (unless it has since been killed off).

See also this question Changing UIView when applicationWillEnterForeground fires which will be the next issue you face if your background image is set in preferences rather than within the app!