accessing a class from another activity
Have following setup:
MainActivity class - extends activity
MyLayout class - extends View
Prefs class - extends PreferenceActivity and implements OnSharedPreferenceChangeListener
MainActivity creates a MyLayout class and sets it as its contentview. Once the user presses on the menu, Prefs class starts where the user can change some settings.
What I want is that, once the user changes a setting, the overloaded OnsharedPreferenceChanged method in the Prefs class will be called and from there I would like to invoke public methods on the MyLayout class that 开发者_StackOverflow社区was created in the MainActivity.
How can I do this?
Don't overload onSharedPreferenceChanged method in preferenceactivity. Get an instance of the shared preference in your MainActivity, and then register an onsharedpreferencechangedlistener on that inside of your mainactivity
SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(this);
pref.registerOnSharedPreferenceChangeListener(prefListener);
And then you can create a new preference listener
OnSharedPreferenceChangeListener prefListener = new OnSharedPreferenceChangeListener() {
@Override
public void onSharedPreferenceChanged(
SharedPreferences sharedPreferences, String key) {
// Do stuff
}
};
You should also unregister the listener in onPause() unless you need it to persist, otherwise unregister it on onStop()
Try making MainActivity
implement OnSharedPreferenceChangeListener
and register it on the onCreate()
method as Falmarri said.
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