问题
How to call android's default LockScreen in activity or service?
I create android application what is like a Optimus G2's knock on function.
But I have some problem.
My Activity has OnStop() or OnDestroy() function, i won't it's call default LockScreen or Sleep and wake.
First, I try PowerManager.gotoSleep(), but it's Android system API. Solution is DevicePolicyManager but I won't use it.
回答1:
Have a look into the Device Administration API: http://developer.android.com/guide/topics/admin/device-admin.html#top
When admin, you can use the Device Policy Manager and lockNow() to lock the screen: http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#lockNow%28%29
To unlock, you have to use the windowmanager to add a flag to the current window.
WindowManager windowManager = Context.getSystemService(Context.WINDOW_SERVICE);
Window window = getWindow();
window.addFlags(windowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
To turn your screen on:
PowerManager powerManager = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
wakeLock = powerManagernewWakeLock(PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP | PowerManager.ON_AFTER_RELEASE, "wakeLock");
wakeLock.acquire();
Don't forget the WAKE_LOCK permission in your manifestfile.
来源：https://stackoverflow.com/questions/22191334/how-to-call-android-default-lockscreen