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Android

Posted by Ilja Daderko
Ilja Daderko
8,953 Points

Issues when adding activity listener (Android Studio & Genymotion)

Hello,

For some reason I get an error message saying "Unfortunately [My App Name Here] Has stopped"

This happens once I add an event listener for onClick, And what confuses me is that I looked through it and it looks correct + there is literary nothing in the project besides few buttons.

My main activity looks like this:

package com.example.braintraininggame.app;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

public class MainActivity extends ActionBarActivity {

    /*
        Declare variables.
    */
    Button getAboutButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment())
                    .commit();
        }

        /*
            Assign views to variables.
         */
        getAboutButton = (Button) findViewById(R.id.buttonAbout);

        /*
            Create Listeners.
         */
        getAboutButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {

            }
        });


    }

    /*
        Methods
     */



    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            return rootView;
        }
    }

}

Any ideas on what can be causing this error?

P.S I did not add my code from fragment_main.xml file so it doesn't get messy, but if you think that it could be cause by it please tell me and I'll post it here. Also, when I created my 4 buttons, the code for those went to fragment_main.xml file, but not activity_main.xml file can this be causing an issue?

1 Answer

Ben Jakuben
STAFF
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

If your button is in the fragment layout, then that would be your issue. You need to initialize it and set the onClickListener in the Fragment's onCreateView() method, which we start talking about around the 2:15 mark in this video: http://teamtreehouse.com/library/build-a-selfdestructing-message-android-app/using-fragments-for-tabs/modifying-fragments-from-the-template