Question

我开发的应用程序具有后台进程，我的应用程序中的一些功能只有在用户打开屏幕并解锁“锁定屏幕”时才会起作用。有 SCREEN_ON ， SCREEN_OFF 和 USER_PRESENT 的操作。

我在 SCREEN_OFF 事件中重置了一个标记并将其设置为 USER_PRESENT 事件，这样可以正常工作但是我还有另一个问题; 在设置中有一个选项＆＃34;立即使用电源按钮锁定＆＃34;如果未选中，设备将在5秒睡眠之前锁定。

现在，如果用户关闭屏幕并在5秒内打开它，则调用SCREEN_OFF事件并且永远不会调用USER_PRESENT事件。

USER_NOT_PRESENT或DEVICE_LOCKED是否有任何操作，以便我可以在那里重置我的旗帜？

注意：如果我知道设置＆＃34; lock_screen_lock_after_timeout＆＃34; 和＆＃34; power_button_instantly_locks＆＃34; ，我可以解决。但是，我可以按照以下方式获取＆＃34; lock_screen_lock_after_timeout＆＃34; 设置，但不知道如何获取＆＃34; power_button_instantly_locks＆＃34;

ContentResolver mResolver = ctx.getContentResolver();
long timeout = Settings.Secure.getLong(mResolver, "lock_screen_lock_after_timeout", 0);

谢谢。任何其他方法也应该受到赞赏。

Answer 1

使用反射获取power_button_instantly_locks的设置值。请参阅以下代码：

/**
  *This function is used to detect the system setting: Power button instantly locks. To see whether this setting is enabled or not.
  * @return true if Power button instantly locks is enabled, otherwise, false.
  */

private boolean isPowerButtonInstantlyLocksOn(){
    String LOCK_PATTERN_UTILS="com.android.internal.widget.LockPatternUtils";
    String POWER_BUTTON_INSTANTLY_LOCKS="getPowerButtonInstantlyLocks";
    boolean isPowerButtonInstantlyLocks=false;
    try{
        Class<?> lockPatternUtilsClass=Class.forName(LOCK_PATTERN_UTILS);
        Object lockPatternUtils=lockPatternUtilsClass.getConstructor(Context.class).newInstance(this);

        // According to the source code of Android 6, the function getPowerButtonInstantlyLocks is declared with a parameter "int userId"
        if (Build.VERSION.SDK_INT>=Build.VERSION_CODES.M){
            Method method = lockPatternUtilsClass.getMethod(POWER_BUTTON_INSTANTLY_LOCKS,new Class[]{int.class});
            isPowerButtonInstantlyLocks=Boolean.valueOf(String.valueOf(method.invoke(lockPatternUtils,userID())));
        }else {
            Method method = lockPatternUtilsClass.getMethod(POWER_BUTTON_INSTANTLY_LOCKS);
            isPowerButtonInstantlyLocks=Boolean.valueOf(String.valueOf(method.invoke(lockPatternUtils,null)));
        }
    }catch (Exception e){
        Crashlytics.logException(e);
        e.printStackTrace();
    }
    return isPowerButtonInstantlyLocks;
}

/**
 * This function is used to check the current userID
 * @return
 */
private int userID(){
    // myUserId is a hidden function in Class UserHandle that we want to use to return the current user ID
    String MY_USER_ID="myUserId";
    int userId=0;

    try{
        // android.os.Process.myUserHandle() is called to get a UserHandle instance
        // myUserHandle requires API 17, but it is OK, cause the function userID() will only be called at API 23
        if (Build.VERSION.SDK_INT>Build.VERSION_CODES.JELLY_BEAN){
            UserHandle userHandle=android.os.Process.myUserHandle();
            Method method = UserHandle.class.getMethod(MY_USER_ID);
            userId=Integer.valueOf(String.valueOf(method.invoke(userHandle,null)));
        }
    }catch (Exception e){
        Crashlytics.logException(e);
        e.printStackTrace();
    }

    return userId;
}

Android：如何知道设备何时被锁定和解锁

1 个答案: