MainActivity.java

package com.lookedpath.firstlesson;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.TextView;


public class MainActivity extends Activity {
    private TextView testo;
    private boolean  next=false;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        testo= (TextView) findViewById(R.id.textView1);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    public void goToNext (View view) {
        if(next==false) {
            next=true;
            testo.setText(R.string.next);
        } else {
            next=false;
            testo.setText(R.string.first);
        }
    }
    public void goToInfo (View view) {
        setContentView(R.layout.info);
    }



    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch(item.getItemId()) {
        case R.id.menu_settings:
            startActivity(new Intent(this, About.class));
            break;
        case R.id.update:
            startActivity(new Intent(this, Update.class));

        }
        return true;
    }

}