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场景:
通常情况我们使用的 app 都不需要用到这个功能。但一些平板的开发就很常见了,我们不希望用户不操作亦或离开平板一段时间后,平板为了省电而自动黑屏或锁屏,那么我们应该怎么做到防止应用再使用过程中禁止系统锁屏呢?
其实很简单,一个我们经常使用却忽略的权限。
<uses-permission android:name="android.permission.WAKE_LOCK" /> /** * A wake lock is a mechanism to indicate that your application needs * to have the device stay on. * <p> * Any application using a WakeLock must request the {@code android.permission.WAKE_LOCK} * permission in an {@code <uses-permission>} element of the application's manifest. * Obtain a wake lock by calling {@link PowerManager#newWakeLock(int, String)}. * </p><p> * Call {@link #acquire()} to acquire the wake lock and force the device to stay * on at the level that was requested when the wake lock was created. * </p><p> * Call {@link #release()} when you are done and don't need the lock anymore. * It is very important to do this as soon as possible to avoid running down the * device's battery excessively. * </p> */源码介绍说,这是一个唤醒机制,就是告诉系统你的应用需要设备一直亮屏,一直开着,不要锁屏。 如果要使用这个功能,需要在配置清单 AndroidMainfest 申请权限,之后使用 acquire() 方法让设备保持亮屏,当你已经完成你的任务或者不再需要保持亮屏了使用 release() 释放。
使用方法 第一种方法:
@Override PRotected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON); setContentView(); }第一种方法:
@Override protected void onResume() { super.onResume(); PowerManager mPowerManager = (PowerManager) getSystemService(POWER_SERVICE); mWakeLock = mPowerManager.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.ON_AFTER_RELEASE,TAG); mWakeLock.acquire(); } @Override protected void onPause() { super.onPause(); if(null != mWakeLock){ mWakeLock.release(); } }随便使用一种方法都可以使你的应用不会导致设备会锁屏或黑屏。
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