Android屏幕常亮、屏幕旋转，home键、电源键、返回键等

> 屏幕常亮，解锁
Android保持屏幕常亮的三种方法- http://blog.youkuaiyun.com/a57565587/article/details/51669520
Android保持屏幕常亮唤醒状态- http://blog.youkuaiyun.com/loongggdroid/article/details/25035059
Activity强制横/竖屏，全屏和常亮- http://blog.youkuaiyun.com/zhuziyue1202/article/details/51501692
妙用View的keepScreenOn保持屏幕常亮，android屏幕常亮- http://blog.youkuaiyun.com/u011449506/article/details/48677313
android亮屏、暗屏、解锁、关闭系统对话的监听事件- http://blog.youkuaiyun.com/w250shini11/article/details/16983177
Android关于屏幕是否亮屏和是否解锁的判断- http://blog.youkuaiyun.com/android_abin/article/details/54970176
// 界面常亮
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

-- 电源锁
//获得系统POWER_SERVICE对象
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE); 
//通过newWakeLock()方法创建WakeLock实例  
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, "这里随便你写,一个TAG而已");  
//最好是放到onReusme方法调用
wl.acquire();
//最好是放到onPause方法调用    
wl.release(); 

> home键、电源键、返回键等的监听
1.监听HOME键、电源键的事件，监听屏幕点亮与变黑的事件？
2.PowerManager（屏幕是否亮屏），KeyguardManager（屏幕是否解锁）?

-- onKeyDown与onBackPressed()的区别？
Android中OnkeyDown事件和OnBackPressed方法区别、兼容、使用- http://blog.youkuaiyun.com/u010717419/article/details/24481537

> 屏幕旋转的角度
-- Activity的getRotate，Camera的setDisplayOrientation，Sensor的onOrientationChanged
Android开发实践：屏幕旋转的处理- http://blog.51cto.com/ticktick/1301209
Android开发实践：屏幕旋转的处理2- http://blog.51cto.com/ticktick/1346579

setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);//横屏设置
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);//竖屏设置
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED);//默认设置

ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE横屏 
ActivityInfo.SCREEN_ORIENTATION_PORTRAIT竖屏 
ActivityInfo.SCREEN_ORIENTATION_REVERSE_PORTRAIT横屏反向 
ActivityInfo.SCREEN_ORIENTATION_REVERSE_LANDSCAPE竖屏反向