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WPFの選択ボックスをクリックしてドラッグします

WPFでマウスクリックアンドドラッグ選択ボックスを実装することは可能ですか？長方形を描き、その点の座標を計算し、このボックス内の他のオブジェクトの位置を評価するだけで実行する必要がありますか？または他の方法はありますか？

サンプルコードやリンクを少し教えていただけますか？

c#wpfmouseselectiondrag
23
rem

これは、ドラッグ選択ボックスを描画するために過去に使用した簡単な手法のサンプルコードです。

XAML：

<Window x:Class="DragSelectionBox.Window1"
    xmlns="http://schemas.Microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.Microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300"
    >
    <Grid
        x:Name="theGrid"
        MouseDown="Grid_MouseDown"
        MouseUp="Grid_MouseUp"
        MouseMove="Grid_MouseMove"
        Background="Transparent"
        >
        <Canvas>
            <!-- This canvas contains elements that are to be selected -->
        </Canvas>

        <Canvas>
            <!-- This canvas is overlaid over the previous canvas and is used to 
                place the rectangle that implements the drag selection box. -->
            <Rectangle
                x:Name="selectionBox"
                Visibility="Collapsed"
                Stroke="Black"
                StrokeThickness="1"
                />
        </Canvas>
    </Grid>
</Window>

C＃：

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
    }

    bool mouseDown = false; // Set to 'true' when mouse is held down.
    Point mouseDownPos; // The point where the mouse button was clicked down.

    private void Grid_MouseDown(object sender, MouseButtonEventArgs e)
    {
        // Capture and track the mouse.
        mouseDown = true;
        mouseDownPos = e.GetPosition(theGrid);
        theGrid.CaptureMouse();

        // Initial placement of the drag selection box.         
        Canvas.SetLeft(selectionBox, mouseDownPos.X);
        Canvas.SetTop(selectionBox, mouseDownPos.Y);
        selectionBox.Width = 0;
        selectionBox.Height = 0;

        // Make the drag selection box visible.
        selectionBox.Visibility = Visibility.Visible;
    }

    private void Grid_MouseUp(object sender, MouseButtonEventArgs e)
    {
        // Release the mouse capture and stop tracking it.
        mouseDown = false;
        theGrid.ReleaseMouseCapture();

        // Hide the drag selection box.
        selectionBox.Visibility = Visibility.Collapsed;

        Point mouseUpPos = e.GetPosition(theGrid);

        // TODO: 
        //
        // The mouse has been released, check to see if any of the items 
        // in the other canvas are contained within mouseDownPos and 
        // mouseUpPos, for any that are, select them!
        //
    }

    private void Grid_MouseMove(object sender, MouseEventArgs e)
    {
        if (mouseDown)
        {
            // When the mouse is held down, reposition the drag selection box.

            Point mousePos = e.GetPosition(theGrid);

            if (mouseDownPos.X < mousePos.X)
            {
                Canvas.SetLeft(selectionBox, mouseDownPos.X);
                selectionBox.Width = mousePos.X - mouseDownPos.X;
            }
            else
            {
                Canvas.SetLeft(selectionBox, mousePos.X);
                selectionBox.Width = mouseDownPos.X - mousePos.X;
            }

            if (mouseDownPos.Y < mousePos.Y)
            {
                Canvas.SetTop(selectionBox, mouseDownPos.Y);
                selectionBox.Height = mousePos.Y - mouseDownPos.Y;
            }
            else
            {
                Canvas.SetTop(selectionBox, mousePos.Y);
                selectionBox.Height = mouseDownPos.Y - mousePos.Y;
            }
        }
    }
}
44
Ashley Davis

InkCanvasを追加し、そのEditingModeをSelectに設定することで、この機能を非常に簡単に取得できます。これは主にタブレットPCのインクの収集とレンダリングを目的としていますが、基本的なデザイナーの表面として非常に簡単に使用できます。

<Window Width="640" Height="480" xmlns="http://schemas.Microsoft.com/winfx/2006/xaml/presentation">
    <InkCanvas EditingMode="Select">
        <Button Content="Button" Width="75" Height="25"/>
        <Button Content="Button" Width="75" Height="25"/>
    </InkCanvas>
</Window>
7
Josh