背景，今天遇项目需要，需要在下载在后台任务运行时（如下载、上传或进行长时间计算），保持 CPU 活动，然后就写了这个实现方法，废话不多说上代码

第一步，再清单AndroidManifest文件声明权限：

   <uses-permission android:name="android.permission.WAKE_LOCK" />

import android.content.Context;
import android.os.PowerManager;import android.util.Log;/***    屏幕唤醒*/
public class ScreenManager {private static final String TAG = "ScreenManager";private PowerManager powerManager;private PowerManager.WakeLock wakeLock;public ScreenManager(Context context) {powerManager = (PowerManager) context.getSystemService(Context.POWER_SERVICE);wakeLock = powerManager.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "MyApp::MyWakelockTag");}public void acquireWakeLock() {if (wakeLock != null && !wakeLock.isHeld()) {wakeLock.acquire();Log.d(TAG, "成功获取WakeLock");} else {Log.d(TAG, "WakeLock已经被持有");}}public void releaseWakeLock() {if (wakeLock != null && wakeLock.isHeld()) {wakeLock.release();Log.d(TAG, "成功释放WakeLock");} else {Log.d(TAG, "WakeLock未被持有");}}
}

 调用如下：

public class MainActivity extends AppCompatActivity {private static final String TAG = "MainActivity";private ScreenManager screenManager;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);screenManager = new ScreenManager(this);Log.d(TAG, "MainActivity 创建完成");}@Overrideprotected void onResume() {super.onResume();screenManager.acquireWakeLock();Log.d(TAG, "MainActivity 恢复");}@Overrideprotected void onPause() {super.onPause();screenManager.releaseWakeLock();Log.d(TAG, "MainActivity 暂停");}@Overrideprotected void onDestroy() {super.onDestroy();screenManager.releaseWakeLock();Log.d(TAG, "MainActivity 销毁");}
}

 以上就是控制设备的电源状态。它可以防止设备在运行某些操作时进入休眠状态，确保应用在需要的时候能够继续运行