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我正在测试如何在单击按钮时绘制一条将按钮连接到另一个按钮的线，我对坐标和坐标感到困惑，settop setleft它们实际上是如何简单地工作的。我知道我们必须设置X2 Y2线的（起点与终点相减），但我真的很困惑要减去什么以及如何做到这一点。

到目前为止，这是我尝试过的：

 int k = 20;
 for (int i = 0; i < 4; i++)
 {
      Button btn = new Button();
      btn.Content = i.ToString();
      btn.Height = 20;
      btn.Width = 20;
      Canvas.SetTop(btn,k); // 20
      Canvas.SetLeft(btn, 20); // 10 
      Canvas1.Children.Add(btn);
      btn.PreviewMouseDown += (source, e) =>
      {
          // No idea how to set X2 , Y2 for the line's end point.
          Line line = new Line();
          //line.X2 = ;
          //line.Y2 = ;
          line.Stroke = Brushes.Red;
          line.StrokeThickness = 4;
          Canvas.SetLeft(line,40); // Suppose this is where the line should start 
          Canvas.SetTop(line ,40); // for button " 0 " .
          Canvas1.Children.Add(line);
      };
      k += 20;
 }
 for (int i = 0; i < 4; i++)
 {
      Button btn2 = new Button();
      btn2.Content = i.ToString();
      btn2.Height = 20;
      btn2.Width = 20;
      Canvas.SetTop(btn2, k); // 20
      Canvas.SetRight(btn2, 20); // 10
      Canvas1.Children.Add(btn2);
      btn2.PreviewMouseDown += (source, e) =>
      {
          //Draw Line to connect here.
      };
      k += 20;
  }

我正在尝试从 btn 到 btn2 画一条线。

预览图像

而且，我如何将按钮调整到同一级别，现在右按钮（btn2）比左按钮（btn）低一点，我想画一条线将右按钮连接到左按钮点击按钮 0 ，所以 0 将画一条线到 0 。

4

1 回答 1

1

虽然您可以通过Canvas四处移动来做到这一点，但最好Buttons使用Canvas.

本质上，您需要有两组坐标，您的LineStart和LineEnd，在这种情况下，它们将从Buttons您单击的两个不同的坐标中获得。

您可以使用Point location = ((Button)source).TransformToAncestor(Canvas1).Transform(new Point(0, 0))来获取被点击的按钮相对于 parent 的位置Canvas。

然后，您需要执行类似的操作来查找您单击的原始对象的位置（您似乎没有存储该对象）。然后，您可以简单地在Points通过设置X1, X2, Y1, Y2值计算的两者之间画一条线。

调整你的例子，你可以做这样的事情（只是为了演示）：

public partial class MainWindow : Window
{
    public Button LastClicked { get; set; }

    public MainWindow()
    {
        InitializeComponent();

        InitButtons();
    }


    public void InitButtons()
    {
        int k = 20;

        for (int i = 0; i < 4; i++)
        {
            Button btn = new Button();
            btn.Content = i.ToString();
            btn.Height = 20;
            btn.Width = 20;
            Canvas.SetTop(btn, k); // 20
            Canvas.SetLeft(btn, 20); // 10 
            Canvas1.Children.Add(btn);
            btn.PreviewMouseDown += (source, e) =>
            {
                if (LastClicked != null)
                {
                    // Get button locations.
                    Point LastClickedLocation = LastClicked.TransformToAncestor(Canvas1).Transform(new Point(0, 0));
                    Point ThisClickedLocation = ((Button)source).TransformToAncestor(Canvas1).Transform(new Point(0, 0));

                    // Stop same side lines.
                    if (LastClickedLocation.X != ThisClickedLocation.X)
                    {
                        Line line = new Line();

                        line.X1 = LastClickedLocation.X;
                        line.Y1 = LastClickedLocation.Y + btn.Height / 2; // Button Middle.
                        line.X2 = ThisClickedLocation.X + btn.Width; // Adjust Left side.
                        line.Y2 = ThisClickedLocation.Y + btn.Height / 2; // Button Middle.

                        line.Stroke = Brushes.Red;
                        line.StrokeThickness = 4;

                        Canvas1.Children.Add(line);
                    }
                }

                LastClicked = (Button)source;
            };
            k += 20;
        }

        k = 20; // Reset k, this is why your buttons weren't aligned.

        for (int i = 0; i < 4; i++)
        {
            Button btn2 = new Button();
            btn2.Content = i.ToString();
            btn2.Height = 20;
            btn2.Width = 20;
            Canvas.SetTop(btn2, k); // 20
            Canvas.SetRight(btn2, 20); // 10
            Canvas1.Children.Add(btn2);

            btn2.PreviewMouseDown += (source, e) =>
            {
                if (LastClicked != null)
                {
                    // Get button locations.
                    Point LastClickedLocation = LastClicked.TransformToAncestor(Canvas1).Transform(new Point(0, 0));
                    Point ThisClickedLocation = ((Button)source).TransformToAncestor(Canvas1).Transform(new Point(0, 0));

                    // Stop same side lines.
                    if (LastClickedLocation.X != ThisClickedLocation.X)
                    {
                        Line line = new Line();

                        line.X1 = LastClickedLocation.X + btn2.Width; // Adjust Left side.
                        line.Y1 = LastClickedLocation.Y + btn2.Height / 2; // Button Middle.
                        line.X2 = ThisClickedLocation.X;
                        line.Y2 = ThisClickedLocation.Y + btn2.Height / 2; // Button Middle.

                        line.Stroke = Brushes.Red;
                        line.StrokeThickness = 4;

                        Canvas1.Children.Add(line);
                    }
                }

                LastClicked = (Button)source;
            };
            k += 20;
        }
    }
}

我不建议使用这个确切的代码，因为它在处理Button点击和决定何时画线方面并不是特别聪明，但它应该演示你所追求的绘图和获取坐标。

于 2013-08-04T12:45:28.053 回答