Android call method from intent

Question

I've this code:

public class MainActivity extends Activity{

    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        intent = new Intent(this, ConnectDialog.class);
        update();
    }

    private void update(){
        if(a)
            startActivity(intent);
        else{
            //code
        }
    }

}

And this:

public class ConnectDialog extends Activity{

    private Button btn;

    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_connect_dialog);
        btn = (Button) findViewById(R.id.button);
        btn.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v) {
                finish();
            }
        });

    }
}

The problem is: when I click on the button of the Intent, is it possible to execute the method update of the main activity again? Thank you very much

"button of the Intent" are you talking about `btn` in `ConnectDialog`? — codeMagic, May 21 '14 at 13:42
You can use [startActivityForResult()](http://stackoverflow.com/questions/18243515/android-going-back-to-previous-activity-with-different-intent-value/18243541#18243541) — codeMagic, May 21 '14 at 13:50

score 1 · Answer 1 · answered May 21 '14 at 13:43

1

Just put the call to update into onResume() of the MainActivity. This way, it will be called at first startup and when the MainActivity is shown again later on:

@Override
protected void onResume(){
    super.onResume;
    update();
}

answered May 21 '14 at 13:43

FD_

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Why didn't I think that before? Thank you – user3503550 May 21 '14 at 13:47

score 0 · Answer 2 · answered May 21 '14 at 13:50

I would use the onActivityResult method.

Change your update method to

int YOUR_RESULT = 100;

private void update(){
    if(a)
        startActivityForResult(intent, YOUR_RESULT);
    else{
        //code
    }
}

then in that same activity, use this method:

public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == YOUR_RESULT) {
        update();
    }
}

If you use this method, the update() method will only get called when coming back from that activity.

score 0 · Answer 3 · answered May 21 '14 at 14:04

if u check the Android Life Cycle u will get the answer why the Update is not executing.. How ever to call the update method on click..

 private void update(){
        if(a)
            startActivityForResult(intent, 0);
        else{
            //code
        }
    }

and use onActivityResult to call the update method again

@Override
    protected void onActivityResult(int arg0, int arg1, Intent arg2) {

        super.onActivityResult(arg0, arg1, arg2);
        update();

    }

Android call method from intent

3 Answers3