سلام برای کلاس اول

 Button b1, b2, b3;
    Intent i;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        MyClickListener myClickListener = new MyClickListener();
        ComponentName cn = new ComponentName(this, SecondActivity.class);
        i = new Intent();
        i.setComponent(cn);

        b1 = (Button) findViewById(R.id.button1);
        b2 = (Button) findViewById(R.id.button2);
        b3 = (Button) findViewById(R.id.button3);

        b1.setOnClickListener(myClickListener);
        b2.setOnClickListener(myClickListener);
        b3.setOnClickListener(myClickListener);
    }

    class MyClickListener implements OnClickListener {

        @Override
        public void onClick(View v) {
            if (b1.equals(v)) {
                i.putExtra("Button", "b1");
                startActivity(i);
            } else if (b2.equals(v)) {
                i.putExtra("Button", "b2");
                startActivity(i);
            } else if (b3.equals(v)) {
                i.putExtra("Button", "b3");
                startActivity(i);
            }
        }
    }
}

و برای کلاس دوم

public class SecondActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.setContentView(R.layout.second_layout);
        Intent i = this.getIntent();
        String button = i.getExtras().getString("Button").toString();

        if ("b1".equals(button)) {
            b1();
        } else if ("b2".equals(button)) {
            b2();
        } else if ("b3".equals(button)) {
            b3();
        }
    }

    private void b1() {
        System.out.println("b1");
    }

    private void b2() {
        System.out.println("b2");
    }

    private void b3() {
        System.out.println("b3");
    }
}

درmanifest هم اکتیویتی را مشخص نمایید.

اگر مشکلی بود بفرمایید