在项目中新建一个libs问价夹，把架包导进来（附件）
到http://www.apkbus.com/android-87258-1-1.html可下载附件
在代码中加入如下代码：
class RefreshHandler extends Handler {
public void handleMessage(Message msg) {
GateMachineUnlock.this.updateUI();
}
public void sleep(long delayMillis) {
this.removeMessages(0);
sendMessageDelayed(obtainMessage(0), delayMillis);
}
};
private void updateUI() {
mRedrawHandler.sleep(15000);
setBrightness(150);
}
//设置屏幕亮度
private void setBrightness(int brightness) {
IHardwareService hardware = IHardwareService.Stub
.asInterface(ServiceManager.getService("hardware"));
if (hardware != null) {
try {
hardware.setScreenBacklight(brightness);
} catch (RemoteException e) {
e.printStackTrace();
}
}
}