c# - WPF DragMove() 导致问题

Question

我想弄清楚是否有一个优雅的解决方案来解决我一直面临的问题。

所以基本上，我设计了一个无边框的加载启动画面，它可以通过拖动完全移动。我发现如果初始屏幕通过 Hide() 隐藏，然后通过 ShowDialog() 显示一个窗口，所有者设置为初始屏幕，就会发生这种情况。事情变得非常错误，但前提是你处于中间拖动状态(按下鼠标左键)。您将无法单击或移动任何内容，甚至 Visual Studio 也会变得无响应，除非您明确地按 alt-tab 退出应用程序。

考虑到我知道何时生成窗口，我在想也许有一种方法可以取消 DragMove 操作，但我没有运气。我发现 DragMove 是同步的，所以我猜它必须从不同的线程或事件回调中取消。

编辑:

public partial class Window_Movable : Window
{
    public Window_Movable()
    {
        InitializeComponent();
    }

    public Boolean CanMove { get; set; } = true;

    private void Window_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (CanMove == false)
            return;

        Task.Factory.StartNew(() => {
            System.Threading.Thread.Sleep(1000);

            Dispatcher.Invoke(() => {
                Hide();
                new Window_Movable() {
                    Title = "MOVABLE 2",
                    CanMove = false,
                    Owner = this
                }.ShowDialog();
            });
        });

        DragMove();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        Console.WriteLine("DING");
    }
}

Answer 1

我有同样的问题，发现 DragMove() 方法有问题。 https://groups.google.com/forum/#!topic/wpf-disciples/7OcuXrf2whc

为了解决我决定拒绝使用它并实现移动逻辑。我结合了一些解决方案 https://www.codeproject.com/Questions/284995/DragMove-problem-help-pls和 C# WPF Move the window

        private bool _inDrag;
        private Point _anchorPoint;
        private bool _iscaptured;

        private void AppWindowWindowOnMouseMove(object sender, MouseEventArgs e)
        {
            if (!_inDrag)
                return;

            if (!_iscaptured)
            {
                CaptureMouse();
                _iscaptured = true;
            }

            var mousePosition = e.GetPosition(this);
            var mousePositionAbs = new Point
            {
                X = Convert.ToInt16(_appWindowWindow.Left) + mousePosition.X,
                Y = Convert.ToInt16(_appWindowWindow.Top) + mousePosition.Y
            };
            _appWindowWindow.Left = _appWindowWindow.Left + (mousePositionAbs.X - _anchorPoint.X);
            _appWindowWindow.Top = _appWindowWindow.Top + (mousePositionAbs.Y - _anchorPoint.Y);
            _anchorPoint = mousePositionAbs;
        }

        private void AppWindowWindowOnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            if (_inDrag)
            {
                _inDrag = false;
                _iscaptured = false;
                ReleaseMouseCapture();
            }
        }

        private void AppWindowWindowOnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            _anchorPoint = e.GetPosition(this);
            _anchorPoint.Y = Convert.ToInt16(_appWindowWindow.Top) + _anchorPoint.Y;
            _anchorPoint.X = Convert.ToInt16(_appWindowWindow.Left) + _anchorPoint.X;
            _inDrag = true;
        }

我花了整个昨天晚上，找到了一个更 hacky 但更实用的解决方案。支持最大化状态，不需要手动坐标计算。

    private bool _mRestoreForDragMove;
    private void OnAppWindowWindowOnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (e.ClickCount == 2)
        {
            if (_appWindowWindow.ResizeMode != ResizeMode.CanResize &&
                _appWindowWindow.ResizeMode != ResizeMode.CanResizeWithGrip)
            {
                return;
            }

            _appWindowWindow.WindowState = _appWindowWindow.WindowState == WindowState.Maximized
                ? WindowState.Normal
                : WindowState.Maximized;
        }
        else
        {
            _mRestoreForDragMove = _appWindowWindow.WindowState == WindowState.Maximized;

            SafeDragMoveCall(e);
        }
    }

    private void SafeDragMoveCall(MouseEventArgs e)
    {
        Task.Delay(100).ContinueWith(_ =>
        {
            Dispatcher.BeginInvoke((Action)
                delegate
                {
                    if (Mouse.LeftButton == MouseButtonState.Pressed)
                    {
                        _appWindowWindow.DragMove();
                        RaiseEvent(new MouseButtonEventArgs(e.MouseDevice, e.Timestamp, MouseButton.Left)
                        {
                            RoutedEvent = MouseLeftButtonUpEvent
                        });
                    }
                });
        });
    }

    private void OnMouseMove(object sender, MouseEventArgs e)
    {
        if (_mRestoreForDragMove)
        {
            _mRestoreForDragMove = false;

            var point = PointToScreen(e.MouseDevice.GetPosition(this));

            _appWindowWindow.Left = point.X - (_appWindowWindow.RestoreBounds.Width * 0.5);
            _appWindowWindow.Top = point.Y;

            _appWindowWindow.WindowState = WindowState.Normal;

            _appWindowWindow.DragMove();

            SafeDragMoveCall(e);
        }
    }

    private void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        _mRestoreForDragMove = false;
    }

事情是在短暂延迟后发送 LeftMouseButtonUp 事件以避免被 DragMove() 阻塞

上次求解的来源: DragMove() and Maximize C# WPF - DragMove and click