Screen Orientation Changing Handler fails in TabActivity

Question

I am developing an Android application with a TabHost in it SDK 7.

My problem is the screen orientation changing handler fails to do the job. This is the scenario:

• The screen is updated well when switching between portrait to landscape and vise versa.
• The screen fails to be updated whenever the black screen (screen saver) is ON or I press the lock button.

What I mean by “fail” to update the screen is:

• When in landscape mode, I press the lock button. After it, I unlock it in portrait mode, the portrait screen is perfectly updated. But, once I rotate to landscape mode, the screen fails to be updated in landscape mode. The landscape mode will be perfectly updated again after I rotate to portrait once again then rotate it again to landscape. When in portrait mode, I press the lock button, none of the fail scenario like above is happened.

This is the method that I used:

• I apply: android:configChanges="keyboardHidden|orientation" in every sceen (both TabActivity and each child of it)
• I apply: onConfigurationChanged() in every child screen
• I didn’t use any landscape res (layout-res and drawable-land). Thus, I only use one xml layout for a screen (landscape and portrait)

Any suggestion or a workaround for my problem? I will appreciate and try every suggestion. Thank you :D

Answer 1

Your solution should be to handle configuration changes properly. Using configChanges is only an optimization for very edge case situations, but you still need to be prepared for the case when your Activity state is saved and your Activity destroyed to relieve memory pressure.

In your Activity:

@Override
public void onSaveInstanceState(Bundle outState) {
    // Put any temporary state for this Activity instance
    // into the outState bundle
}

Then in onCreate():

@Override
public void onCreate(Bundle savedInstanceState) {
    if (savedInstanceState != null) {
        // Retrieve and reassign any state that you saved
    }
}

Also see Handling Runtime Changes