Android 监听屏幕是否锁屏的实例代码

package com.app.lib; 
import android.content.BroadcastReceiver; 
import android.content.Context; 
import android.content.Intent; 
import android.content.IntentFilter; 
import android.os.PowerManager; 
/** 
 * Created by ${zyj} on 2016/6/21. 
 */ 
public class ScreenListener { 
  private Context mContext; 
  private ScreenBroadcastReceiver mScreenReceiver; 
  private ScreenStateListener mScreenStateListener; 
  public ScreenListener(Context context) { 
    mContext = context; 
    mScreenReceiver = new ScreenBroadcastReceiver(); 
  } 
  /** 
   * screen状态广播接收者 
   */ 
  private class ScreenBroadcastReceiver extends BroadcastReceiver { 
    private String action = null; 
    @Override 
    public void onReceive(Context context, Intent intent) { 
      action = intent.getAction(); 
      if (Intent.ACTION_SCREEN_ON.equals(action)) { // 开屏 
        mScreenStateListener.onScreenOn(); 
      } else if (Intent.ACTION_SCREEN_OFF.equals(action)) { // 锁屏 
        mScreenStateListener.onScreenOff(); 
      } else if (Intent.ACTION_USER_PRESENT.equals(action)) { // 解锁 
        mScreenStateListener.onUserPresent(); 
      } 
    } 
  } 
  /** 
   * 开始监听screen状态 
   * 
   * @param listener 
   */ 
  public void begin(ScreenStateListener listener) { 
    mScreenStateListener = listener; 
    registerListener(); 
    getScreenState(); 
  } 
  /** 
   * 获取screen状态 
   */ 
  private void getScreenState() { 
    PowerManager manager = (PowerManager) mContext 
        .getSystemService(Context.POWER_SERVICE); 
    if (manager.isScreenOn()) { 
      if (mScreenStateListener != null) { 
        mScreenStateListener.onScreenOn(); 
      } 
    } else { 
      if (mScreenStateListener != null) { 
        mScreenStateListener.onScreenOff(); 
      } 
    } 
  } 
  /** 
   * 停止screen状态监听 
   */ 
  public void unregisterListener() { 
    mContext.unregisterReceiver(mScreenReceiver); 
  } 
  /** 
   * 启动screen状态广播接收器 
   */ 
  private void registerListener() { 
    IntentFilter filter = new IntentFilter(); 
    filter.addAction(Intent.ACTION_SCREEN_ON); 
    filter.addAction(Intent.ACTION_SCREEN_OFF); 
    filter.addAction(Intent.ACTION_USER_PRESENT); 
    mContext.registerReceiver(mScreenReceiver, filter); 
  } 
  public interface ScreenStateListener {// 返回给调用者屏幕状态信息 
    public void onScreenOn(); 
    public void onScreenOff(); 
    public void onUserPresent(); 
  } 
} 

package com.app.lib; 
import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.widget.Toast; 
public class MainActivity extends AppCompatActivity { 
  private ScreenListener screenListener ; 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    screenListener = new ScreenListener( MainActivity.this ) ; 
    screenListener.begin(new ScreenListener.ScreenStateListener() { 
      @Override 
      public void onScreenOn() { 
        Toast.makeText( MainActivity.this , "屏幕打开了" , Toast.LENGTH_SHORT ).show(); 
      } 
      @Override 
      public void onScreenOff() { 
        Toast.makeText( MainActivity.this , "屏幕关闭了" , Toast.LENGTH_SHORT ).show(); 
      } 
      @Override 
      public void onUserPresent() { 
        Toast.makeText( MainActivity.this , "解锁了" , Toast.LENGTH_SHORT ).show(); 
      } 
    }); 
  } 
}