Prevent iOS from taking screen capture of app before going into background
You all might know that iOS takes a screen shot of your application before throwing it into the background. This is usually for a better User experience like quick animation to bring the app back and so on. I don't want my app screen shot to be stored on the device, but I want the multitasking to still exist.
I came out with a solution but I'm not sure if I'm heading in the right direction. So, when the applicationDidEnterBackground is called -- I put in an overlay image that will be captured by the OS, and once the app enters foreground, I will remove the overlay. I'm not sure if this is going to work but I'm on my way to implement this. Meanwhile, any other thoughts on this will help me figure out the optimal way of attacking this issue.
Answer
You are on the right track. This is Apple's recommended way to do this as noted in the iOS Application Programming Guide:
Remove sensitive information from views before moving to the background. When an application transitions to the background, the system takes a snapshot of the application’s main window, which it then presents briefly when transitioning your application back to the foreground. Before returning from your
applicationDidEnterBackground:method, you should hide or obscure passwords and other sensitive personal information that might be captured as part of the snapshot.