Question

I have created two classes. I want to have a button on class 1 (MainActivity) that when it is pressed, it will take me to class 2 (Alphabet). I have tried numerous ways of doing it and I have been unsuccessful. Here is my original code below. Can anyone help me?
Sorry, I am new to app developing.

package com.example.lullabymain;


import android.os.Bundle;  
import android.app.Activity;
import android.view.Menu;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.view.View;
import android.view.View.OnClickListener;




public class MainActivity extends Activity implements OnClickListener {

private MediaPlayer mp;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // new code

        setVolumeControlStream(AudioManager.STREAM_MUSIC);
        findViewById(R.id.button1).setOnClickListener(this);
        findViewById(R.id.button2).setOnClickListener(this);
        findViewById(R.id.button3).setOnClickListener(this);
        findViewById(R.id.button4).setOnClickListener(this);
        findViewById(R.id.button5).setOnClickListener(this);
    }


    public void onClick(View v) {
        int resId = 0;
        switch (v.getId()) {
        case R.id.button1: resId = R.raw.rockabye; break;
        case R.id.button2: resId = R.raw.hushlittlebaby; break;
        case R.id.button3: resId = R.raw.twinkle; break;
        case R.id.button4: resId = R.raw.hickory; break;
        case R.id.button5: resId = R.raw.oldmcd; break;


        }
        //release any resources from previous mediaplayer
        if (mp != null) {
            mp.release();
        }
        //create a new mediaplayer to play this sound
        mp = MediaPlayer.create(this, resId);
        mp.start();

    }


    @Override
    protected void  onStop()
    {
        //stop audio
        super.onStop();
        mp.stop();
    }


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

The code below is the code that I attempted which includes ‘Intent’

package com.example.lullabymain;

import android.os.Bundle; 

import android.app.Activity;

import android.content.Intent;

import android.view.Menu;

import android.media.AudioManager;

import android.media.MediaPlayer;

import android.view.View;

import android.view.View.OnClickListener;

public class MainActivity extends Activity implements OnClickListener {
    private MediaPlayer mp;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // new code
        **View button6 = findViewById(R.id.button6);
        button6.setOnClickListener(this);**       
        setVolumeControlStream(AudioManager.STREAM_MUSIC);
        findViewById(R.id.button1).setOnClickListener(this);
        findViewById(R.id.button2).setOnClickListener(this);
        findViewById(R.id.button3).setOnClickListener(this);
        findViewById(R.id.button4).setOnClickListener(this);
        findViewById(R.id.button5).setOnClickListener(this);
    }


    public void onClick(View v) {
        int resId = 0;
        switch (v.getId()) {
        case R.id.button1: resId = R.raw.rockabye; break;
        case R.id.button2: resId = R.raw.hushlittlebaby; break;
        case R.id.button3: resId = R.raw.twinkle; break;
        case R.id.button4: resId = R.raw.hickory; break;
        case R.id.button5: resId = R.raw.oldmcd; break;
        **case R.id.button6:
            Intent i = new Intent(this, Alphabet.class);
            startActivity(i);
            break;**

        }
        //release any resources from previous mediaplayer
        if (mp != null) {
            mp.release();
        }
        //create a new mediaplayer to play this sound
        mp = MediaPlayer.create(this, resId);
        mp.start();

    }


    @Override
    protected void  onStop()
    {
        //stop audio
        super.onStop();
        mp.stop();
    }


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

Answer 1

Currently in MainActivity Activity you are not adding setOnClickListener to button6 but in onClick method you are trying to start Activity on button6 click . to get your code working add setOnClickListener to button6 also as

public class MainActivity extends Activity implements OnClickListener {
private MediaPlayer mp;
Button button6 ;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    // new code
    button6 = (Button)findViewById(R.id.button6);
    button6.setOnClickListener(this);      

and register Alphabet Activity in Manifest as :

<activity android:name=".Alphabet" />