安卓开发之动态注册广播(锁屏和解锁案例)

package com.lidaochen.test001;

import android.content.Intent;
import android.content.IntentFilter;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

public class MainActivity extends AppCompatActivity {
    private ScreenReceiver screenReceiver;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 动态注册广播接收者
        screenReceiver = new ScreenReceiver();
        // 创建IntentFilter对象
        IntentFilter filter = new IntentFilter();
        // 添加要注册的action
        filter.addAction("android.intent.action.SCREEN_OFF");
        filter.addAction("android.intent.action.SCREEN_ON");
        // 动态注册广播接收者
        registerReceiver(screenReceiver, filter);
    }

}

package com.lidaochen.test001;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;

public class ScreenReceiver extends BroadcastReceiver {

    // 当我们进行屏幕锁屏和解锁时，执行下面的方法
    @Override
    public void onReceive(Context context, Intent intent) {
        // 获取当前广播的事件类型
        String action = intent.getAction();
        if("android.intent.action.SCREEN_OFF".equals(action))
        {
            System.out.println("锁屏！");
            Log.e("screen","锁屏");
        }
        else if("android.intent.action.SCREEN_ON".equals(action))
        {
            System.out.println("解锁！");
            Log.e("screen","解锁");
        }
    }
}