源碼：

　　base\services\core\java\com\android\server\display\DisplayPowerState.java

功能：

　　對LightsService封裝了一層

　　對上：提供mProperty.setValue方法

　　對下：調用LightsService.setBrightness方法，設置brightness

源碼分析：

　　構建了mProperty.setValue這個方法供調用，傳入brightness值

public static final IntProperty<DisplayPowerState> SCREEN_BRIGHTNESS =new IntProperty<DisplayPowerState>("screenBrightness") {public void setValue(DisplayPowerState object, int value)object.setScreenBrightness(value); // DisplayPowerState.setScreenBrightnessmScreenBrightness = brightness;scheduleScreenUpdate();postScreenUpdateThreadSafe();mHandler.post(mScreenUpdateRunnable); // 執行mScreenUpdateRunnable.run()brightness = mScreenBrightness;mPhotonicModulator.setState(mScreenState, brightness);mPendingBacklight = backlight; // brightness最終保存在PhotonicModulator.mPendingBacklightmLock.notifyAll(); // 喚醒PhotonicModulator線程

notifyAll將喚醒PhotonicModulator線程，最終調用LightsService.setBrightness，請查看LightsService篇

public void run() {for (;;) {backlight = mPendingBacklight;backlightChanged = (backlight != mActualBacklight);if (!stateChanged && !backlightChanged) {mLock.wait(); // 等待continue;}mActualBacklight = backlight; // 更新數據if (backlightChanged)setBrightness(backlight);mBacklight.setBrightness(backlight); // mLights[LIGHT_ID_BACKLIGHT].setBrightness(backlight) } }

轉載于:https://www.cnblogs.com/zzss-feature/p/8302629.html

總結

以上是生活随笔為你收集整理的DisplayPowerState的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。