android 图片按钮

<ImageButton
        android:id="@+id/play"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginBottom="26dp"
        android:layout_marginRight="104dp"
        android:background="@drawable/buton_style" />

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:background="#000000"
    tools:context=".MainActivity" >

    <ImageButton
        android:id="@+id/stop"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/play"
        android:layout_marginRight="14dp"
        android:layout_toLeftOf="@+id/play"
        android:padding="0dp"
        android:src="@drawable/buton2_style" />

    <ImageButton
        android:id="@+id/play"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginBottom="26dp"
        android:layout_marginRight="104dp"
        android:background="@drawable/buton_style" />
</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:state_pressed="true" android:drawable="@drawable/play_press" />
    <item android:state_focused="true" android:drawable="@drawable/play_press" />
    <item android:drawable="@drawable/play" />

</selector>

package com.example.mediaplayer;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageButton;

public class MainActivity extends Activity {

	ImageButton start;
	ImageButton stop;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        findView();
        start.setOnClickListener(startlis);
        stop.setOnClickListener(stoplis);
    }
    private OnClickListener startlis=new OnClickListener(){
    	@Override
    	public void onClick(View v){
    		startService(new Intent(MainActivity.this,Music.class));
    	}
    };
    private OnClickListener stoplis=new OnClickListener(){
    	@Override
    	public void onClick(View v){
    		stopService(new Intent(MainActivity.this,Music.class));
    	}
    };
    public void findView(){
    	start=(ImageButton)findViewById(R.id.play);
    	stop=(ImageButton)findViewById(R.id.stop);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
    
}