Android屏幕解锁和点亮

有些场景需要程序自动点亮屏幕,解开屏幕锁,以方便用户即时操作,下面用代码来实现这一功能:

1. //得到键盘锁管理器对象
2. KeyguardManager km= (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
3. //参数是LogCat里用的Tag
4. KeyguardLock kl = km.newKeyguardLock("unLock");
5. //解锁
6. kl.disableKeyguard();
8. //获取电源管理器对象
9. PowerManager pm=(PowerManager) getSystemService(Context.POWER_SERVICE);
10. //获取PowerManager.WakeLock对象,后面的参数|表示同时传入两个值,最后的是LogCat里用的Tag
11. PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.ACQUIRE_CAUSES_WAKEUP | PowerManager.SCREEN_DIM_WAKE_LOCK, "bright");
12. //点亮屏幕
13. wl.acquire();
14. //释放
15. wl.release();

需要在AndroidManifest.xml添加权限:

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

flags参数说明:

1. PARTIAL_WAKE_LOCK: Screen off, keyboard light off
2. SCREEN_DIM_WAKE_LOCK: screen dim, keyboard light off
3. SCREEN_BRIGHT_WAKE_LOCK: screen bright, keyboard light off
4. FULL_WAKE_LOCK: screen bright, keyboard bright

ACQUIRE_CAUSES_WAKEUP：Normal wake locks don't actually turn on the illumination. Instead, they cause the illumination to remain on once it turns on (e.g. from user activity). This flag will force the screen and/or keyboard to turn on immediately, when the WakeLock is acquired. A typical use would be for notifications which are important for the user to see immediately.

ON_AFTER_RELEASE：f this flag is set, the user activity timer will be reset when the WakeLock is released, causing the illumination to remain on a bit longer. This can be used to reduce flicker if you are cycling between wake lock conditions.