Question

我有一个自定义WPF控件，它由单个TextBox

组成

<UserControl HorizontalAlignment="Left" x:Class="WPFDiagramDesignerControl.Components.UcWBSBlock"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Height="100" Width="100" IsEnabled="True">

    <Grid >
        <TextBox x:Name="txtBox" IsEnabled="True"   Background="AntiqueWhite"  Margin="10,10,10,10" TextWrapping="Wrap"> </TextBox>
    </Grid>

</UserControl>

控件放在Canvas上，名为MyDesigner。

我只想在单击文本框并移动鼠标时才能在画布上移动控件。当我点击控件和文本框的边框之间的边距时，我不想移动控件。我开始编写代码，它看起来像那样

public partial class UcWBSBlock : UserControl
{

    bool textChanged = false;
    bool isClicked = false;
    Point startPoint;
    DesignerItem parentItem;
    DesignerCanvas parentCanvas;

    public UcWBSBlock()
    {

        InitializeComponent();

        txtBox.MouseDoubleClick+=new MouseButtonEventHandler(txtBox_MouseDoubleClick);
        txtBox.MouseMove+=new MouseEventHandler(txtBox_MouseMove);
        txtBox.PreviewMouseDown+=new MouseButtonEventHandler(txtBox_PreviewMouseDown);
        txtBox.PreviewMouseUp+=new MouseButtonEventHandler(txtBox_PreviewMouseUp);
        txtBox.Cursor = Cursors.SizeAll;

    }

    private void txtBox_MouseMove(object sender, RoutedEventArgs e)
    {
        if (isClicked)
        {
            Point mousePos = Mouse.GetPosition(parentCanvas);

            parentItem = this.Parent as DesignerItem;
            parentCanvas = parentItem.Parent as DesignerCanvas;
            Point relativePosition = Mouse.GetPosition(parentCanvas);
            DesignerCanvas.SetLeft(parentItem,DesignerCanvas.GetLeft(parentItem) -  (startPoint.X - mousePos.X));
            DesignerCanvas.SetTop(parentItem, DesignerCanvas.GetTop(parentItem) - (startPoint.Y - mousePos.Y));
        }  
    }

    private void txtBox_PreviewMouseDown(object sender, RoutedEventArgs e)
    {
        if (!isClicked)
        {
            isClicked = true;
            parentItem = this.Parent as DesignerItem;
            parentCanvas = parentItem.Parent as DesignerCanvas;
            startPoint = Mouse.GetPosition(parentCanvas);
        }
    }

    private void txtBox_PreviewMouseUp(object sender, RoutedEventArgs e)
    {
        isClicked = false;
    }
}

}

然而我的控制不动:(我做错了什么？很难调试这个：）

Answer 1

您正在设置父项的左/顶部，而不是您的控件：

DesignerCanvas.SetLeft(parentItem,DesignerCanvas.GetLeft(parentItem) -  (startPoint.X - mousePos.X));
DesignerCanvas.SetTop(parentItem, DesignerCanvas.GetTop(parentItem) - (startPoint.Y - mousePos.Y));

应该（可能）是这样的：

DesignerCanvas.SetLeft(this,DesignerCanvas.GetLeft(this) -  (startPoint.X - mousePos.X));
DesignerCanvas.SetTop(this, DesignerCanvas.GetTop(this) - (startPoint.Y - mousePos.Y));

用鼠标移动文本框

1 个答案: