When I try my app with Android KitKat I have an error in PreferenceActivity.
Subclasses of PreferenceActivity must override isValidFragment(String) to verify that the Fragment class is valid! com.crbin1.labeltodo.ActivityPreference has not checked if fragment com.crbin1.labeltodo.StockPreferenceFragment is valid
In documentation I find the following explanation
protected boolean isValidFragment (String fragmentName)
Added in API level 19
Subclasses should override this method and verify that the given fragment is a valid type to be attached to this activity. The default implementation returns true for apps built for android:targetSdkVersion older than KITKAT. For later versions, it will throw an exception.
I don't find any example to resolve the problem.
Try this... this is how we check validity of fragment.
protected boolean isValidFragment(String fragmentName) {
return StockPreferenceFragment.class.getName().equals(fragmentName);
}