MainActivity.java

package com.example.devcon_exampl1;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity {
    private ImageView homeButton;

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

    private void initFields() {
        homeButton = (ImageView) findViewById(R.id.home_button);
        homeButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                Toast toast = Toast.makeText(MainActivity.this, "Pulsado Home", Toast.LENGTH_SHORT);
                toast.show();
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }


    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                Toast toast = Toast.makeText(MainActivity.this, "HOME", Toast.LENGTH_SHORT);
                toast.show();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

}