如何检查UWP上的用户是否空闲？

Question

如果用户闲置一段时间,我想创建一个超时并导航到主页面的函数.经过一番研究,我发现ThreadPoolTimer应该适合我的需要.测试它我决定使用10秒的间隔.

    timer =ThreadPoolTimer.CreatePeriodicTimer(Timer_Tick,TimeSpan.FromSeconds(10));

这就是我不知所措的地方.我无法找到一种方法来检查UWP上的用户输入,而无需单独检查PointerPressed,PointerExited等.所以我做了一些挖掘,我找到了一个代码块,如果用户应该给你一个布尔值闲置与否.

    public static uint GetIdleTime()
    {
        LASTINPUTINFO lastInPut = new LASTINPUTINFO();
        lastInPut.cbSize = (uint)Marshal.SizeOf(lastInPut);
        GetLastInputInfo(ref lastInPut);

        return ((uint)Environment.TickCount - lastInPut.dwTime);
    }

    public static bool IsUserIdle()
    {
        uint idleTime = (uint)Environment.TickCount - GetLastInputEventTickCount();
       if (idleTime > 0)
       {
           idleTime = (idleTime / 1000);
       }
       else
       {
           idleTime = 0;
       }
       //user is idle for 10 sec
       bool b = (idleTime >= 10);
       return b;
    }

    private static uint GetLastInputEventTickCount()
    {
        LASTINPUTINFO lii = new LASTINPUTINFO();
        lii.cbSize = (uint)Marshal.SizeOf(lii);
        lii.dwTime = 0;
        uint p = GetLastInputInfo(ref lii) ? lii.dwTime : 0;
        return p;
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct LASTINPUTINFO
    {
        public static readonly int SizeOf = Marshal.SizeOf<LASTINPUTINFO>();
        [MarshalAs(UnmanagedType.U4)]
        public UInt32 cbSize;
        [MarshalAs(UnmanagedType.U4)]
        public UInt32 dwTime;
    }

    [DllImport("user32.dll")]
    private static extern bool GetLastInputInfo(ref LASTINPUTINFO plii);

然后我在tick函数中调用函数并使用条件语句,如果IsUserIdle()等于true,则导航到主页面.

    public static void Timer_Tick(object sender)
    {
       if (IsUserIdle() == true)
       {
           Frame.Navigate(typeof(MainPage));
       }                                        
    }

但是当我开始它没有任何反应时,在我设置了几个断点后,我发现即使在10秒不活动之后,IsUserIdle()也永远不会返回真值.我完全陷入困境,所以任何帮助都会受到赞赏.

Answer 1

Windows应用商店应用不支持GetLastInputInfo:

支持的最低客户端:Windows 2000 Professional [ 仅限桌面应用程序 ]

我不知道有任何内在的UWP API可以检测用户是否处于空闲状态,但是完全可以启动自己的机制.

我无法找到一种方法来检查UWP上的用户输入,而无需单独检查PointerPressed,PointerExited等.

这种方法有什么不好的？这是我的尝试:

App.xaml.cs

public sealed partial class App : Application
{
    public static new App Current => (App)Application.Current;

    public event EventHandler IsIdleChanged;

    private DispatcherTimer idleTimer;

    private bool isIdle;
    public bool IsIdle
    {
        get
        {
            return isIdle;
        }

        private set
        {
            if (isIdle != value)
            {
                isIdle = value;
                IsIdleChanged?.Invoke(this, EventArgs.Empty);
            }
        }
    }

    protected override void OnLaunched(LaunchActivatedEventArgs e)
    {
        idleTimer = new DispatcherTimer();
        idleTimer.Interval = TimeSpan.FromSeconds(10);  // 10s idle delay
        idleTimer.Tick += onIdleTimerTick;
        Window.Current.CoreWindow.PointerMoved += onCoreWindowPointerMoved;
    }

    private void onIdleTimerTick(object sender, object e)
    {
        idleTimer.Stop();
        IsIdle = true;
    }

    private void onCoreWindowPointerMoved(CoreWindow sender, PointerEventArgs args)
    {
        idleTimer.Stop();
        idleTimer.Start();
        IsIdle = false;
    }
}

MainPage.xaml.cs中

public sealed partial class MainPage : Page
{
    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
        App.Current.IsIdleChanged += onIsIdleChanged;
    }

    protected override void OnNavigatedFrom(NavigationEventArgs e)
    {
        App.Current.IsIdleChanged -= onIsIdleChanged;
    }

    private void onIsIdleChanged(object sender, EventArgs e)
    {
        System.Diagnostics.Debug.WriteLine($"IsIdle: {App.Current.IsIdle}");
    }
}

当指针在应用程序窗口内没有移动10秒时检测到空闲.这也适用于仅限触摸的应用程序(如移动应用程序),因为PointerMoved也会在点击窗口时触发.