getLastConfigurationInstance gives a Null Pointer Exception

Question

I am trying to retain my Activity Configuration using

@Override
public Object onRetainNonConfigurationInstance() {
// TODO Auto-generated method stub      
    ArrayList<String> array = new ArrayList<String>();
    array = alarmsArrayList;
    return array;   
}

And when i try

ArrayList<String> data = (ArrayList<String>) getLastNonConfigurationInstance();
    if (data.size() != 0) 
    {
        alarmsArrayList = data;
        alarmList.setAdapter(adapter);
        startProgress(SingleAlarm.this.getCurrentFocus());
    }
    else
    {
        startProgress(SingleAlarm.this.getCurrentFocus());
    }

It gives a Null Pointer Exception.

Is there a way to retain every configuration of the Activity, like the CheckBox status?

Answer 1

there are plenty of ways to save configuration or states of views in Android. you can read this doc

here is almost a same question asked.

or if you want you can create save views current state in database or shared preferences.