Example Java code demoing how to give a button the functionality to switch between activities.

switchActivityExample

public class ExampleActivity extends Activity {
  
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		//Tells Android which XML file holds this class' information
		setContentView(R.layout.ExampleActivityXMLFile);
		
		//Sets up the chosen button
		Button demo = (Button) findViewById(R.id.exampleButton);
        demo.setOnClickListener( new OnClickListener() {
        	
        	@Override
        	public void onClick(View v){
        	  //ExampleActivity is the Activity we're in, TargetActivity is the Activity we'd like to show
        		startActivity(new Intent(ExampleActivity.this, TargetActivity.class));
        	}

        });
}