Question

I have two activities A, B . Now from A i call B by pressing a button (using startActivity()) , then press Back key to go back to A . Now when i press Button again to go to B , fresh activity is called (as expected).

Now can someone tell me how to show old previous state of B ?

I have read this article
Saving Android Activity state using Save Instance State , but couldn’t help myself 🙁

public class B extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main1);

    if(savedInstanceState!=null){
        EditText editText=(EditText)findViewById(R.id.editText1);
        editText.setText(savedInstanceState.getString("EditBox"));
    }
}

@Override
protected void onSaveInstanceState(Bundle onSaveInstanceState) {
    System.out.println("B.onSaveInstanceState()");
    super.onSaveInstanceState(onSaveInstanceState);
    onSaveInstanceState.putString("EditBox","Hello");
}

@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
    System.out.println("B.onRestoreInstanceState()");
    super.onRestoreInstanceState(savedInstanceState);
    EditText editText=(EditText)findViewById(R.id.editText1);
    editText.setText(savedInstanceState.getString("EditBox"));
}}

My Class A

public class A extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    Button button=(Button)findViewById(R.id.button1);
    button.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
             Intent i=new Intent(StartActivityforresultActivity.this,B.class);
             startActivity(i);
        }
    });


}

Answer 1

With what it sounds like you’re trying to do you have two options:
1. Save the state of B when B’s onDestroy or onBackPressed is called. You’ll have to save this to memory or write it out using some sort of persistence (SharedPreferences, local file, etc). Then whenever B is started, check to see if that data exists and use it to load the state.
2. Override onBackPressed so that when it is pressed you aren’t calling super.onBackPressed. Instead start an instance of activity A and set your intent’s flags to be FLAG_ACTIVITY_REORDER_TO_FRONT before calling startActivity. So something like this:

    Intent intent = new Intent(this, A.class);
    intent.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
    startActivity(intent);

Now when you hit back, it should find the instance of A that is in your activity stack and just bring it to the front. You may have to add the same flag whenever you start B as well.