Android屏幕保持常亮

拼搏现实的明天。 2022-10-21 11:52 186阅读 0赞

#### 一、需求背景 ####

当我们在玩游戏或者看视频的时候不希望app黑屏，那么就需要在app使用的时候处于常量状态。

#### 二、实现方案 ####

**1、使用PowerManager.WakeLock**

PowerManager powerManager = (PowerManager)getSystemService(POWER_SERVICE);
    if (powerManager != null) { 
             wakeLock = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK, "WakeLock");
     　　　　 wakeLock.acquire();  //开启屏幕常亮
     　　　　//wakeLock.release(); //释放wakeLock,注意此方法可能出现异常.具体可看源码
     }

**2、MediaPlayer有自带的方法防止屏幕黑屏**  
mediaPlayer.setScreenOnWhilePlaying(true);

源码如下：

/** * Control whether we should use the attached SurfaceHolder to keep the * screen on while video playback is occurring. This is the preferred * method over {@link #setWakeMode} where possible, since it doesn't * require that the application have permission for low-level wake lock * access. * * @param screenOn Supply true to keep the screen on, false to allow it * to turn off. */
     public void setScreenOnWhilePlaying(boolean screenOn) { 
         if (mScreenOnWhilePlaying != screenOn) { 
             if (screenOn && mSurfaceHolder == null) { 
                 Log.w(TAG, "setScreenOnWhilePlaying(true) is ineffective without a SurfaceHolder");
             }
             mScreenOnWhilePlaying = screenOn;
             updateSurfaceScreenOn();
         }
     }
    　　......
    
     private void updateSurfaceScreenOn() { 
         if (mSurfaceHolder != null) { 　　　　　　  
             mSurfaceHolder.setKeepScreenOn(mScreenOnWhilePlaying && mStayAwake);   
         }
     }

**3、在view中设置**  
setKeepScreenOn(true/false)，同样可以在xml中设置android:keepScreenOn=""，只要View可见即生效。

**4、通过添加flag的方法设置**

/** * 是否开启屏幕常亮 */
    private var enableKeepScreenOn = false
    
    /** * activity 生命周期监听器 */
    private var mActivityLifecycleCallbacks = object : Application.ActivityLifecycleCallbacks { 
        override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) { 
            //在activity创建的时候设置屏幕保持常亮
            if (enableKeepScreenOn) { 
                activity.window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
            }
        }
    
        override fun onActivityStarted(activity: Activity) { 
        }
    
        override fun onActivityResumed(activity: Activity) { 
        }
    
        override fun onActivityPaused(activity: Activity) { 
        }
    
        override fun onActivityStopped(activity: Activity) { 
        }
    
        override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) { 
        }
    
        override fun onActivityDestroyed(activity: Activity) { 
        }
    
    }
    
    /** * 设置保持屏幕常亮状态 */
    fun setKeepScreenOn(enable: Boolean) { 
    	enableKeepScreenOn = enable
    }