android4.4系统永不锁屏

android4.4frameworksasepackagesKeyguardsrccomandroidkeyguardKeyguardViewMediator.java

    /**
     * External apps (like the phone app) can tell us to disable the keygaurd.
     */
    private boolean mExternallyEnabled = false;//系统此属性默认是true。本类把全部的mExternallyEnabled  此属性改成false。系统永远就不锁屏了