Question

我有两个按钮，需要用线连接它们。我将线坐标绑定到按钮位置。

我需要通过代码添加此绑定。

在XAML中，这项工作非常好：

<Button x:Name="button1" Width="10" Height="10" Canvas.Left="150"  Canvas.Top="150"/>
<Button x:Name="button2" Width="10" Height="10" Canvas.Left="250"  Canvas.Top="100"/>

<Line x:Name="testLine" Stroke="Black"
      X1="{Binding ElementName=button1, Path=(Canvas.Left)}"
      Y1="{Binding ElementName=button1, Path=(Canvas.Top)}"
      X2="{Binding ElementName=button2, Path=(Canvas.Left)}"
      Y2="{Binding ElementName=button2, Path=(Canvas.Top)}"/>

现在，在代码中，我尝试了：

    Binding b = new Binding("(Canvas.Left)");
    b.ElementName = "button1";
    testLine.SetBinding(System.Windows.Shapes.Line.X1Property, "(Canvas.Left)");

但这不起作用......（

编辑：

动态创建元素时存在一个问题：

Button button1 = new Button();
Canvas.SetLeft(button1, 50);
Canvas.SetTop(button1, 50);
button1.Name = "be1";
mainCanvas.Children.Add(button1);

Button button2 = new Button();
Canvas.SetLeft(button2, 150);
Canvas.SetTop(button2, 150);
button2.Name = "be2";
mainCanvas.Children.Add(button2);

Binding b1 = new Binding() { ElementName = "be1", Path = new PropertyPath("(Canvas.Left)") };
Binding b2 = new Binding() { ElementName = "be2", Path = new PropertyPath("(Canvas.Left)") };

testLine.SetBinding(System.Windows.Shapes.Line.X1Property, b1);
testLine.SetBinding(System.Windows.Shapes.Line.X2Property, b2);

似乎“be1”不存在或者我不知道是什么......

button1.RegisterName(button1.Name, button1); //does not help, error...

Answer 1

你确定你不是故意的：

    Binding b = new Binding("(Canvas.Left)");
    b.ElementName = "button1";
    testLine.SetBinding(System.Windows.Shapes.Line.X1Property, b);

编辑：

根本不需要元素名称：

Button button1 = new Button();
Canvas.SetLeft(button1, 50);
Canvas.SetTop(button1, 50);
mainCanvas.Children.Add(button1);

Button button2 = new Button();
Canvas.SetLeft(button2, 150);
Canvas.SetTop(button2, 150);
mainCanvas.Children.Add(button2);

//juse Source reference not ElementName
Binding b1 = new Binding() { Source = button1, Path = new PropertyPath("(Canvas.Left)") };
Binding b2 = new Binding() { Source = button2, Path = new PropertyPath("(Canvas.Left)") };

testLine.SetBinding(System.Windows.Shapes.Line.X1Property, b1);
testLine.SetBinding(System.Windows.Shapes.Line.X2Property, b2);

Answer 2

可能只是打字错误。您创建绑定但不使用它。尝试：

testLine.SetBinding(System.Windows.Shapes.Line.X1Property, b);

Answer 3

尝试使用SetBinding的其他重载...您在代码中创建了一个新绑定，但实际上并没有使用它。

Binding b = new Binding("(Canvas.Left)");
b.ElementName = "button1";
testLine.SetBinding(System.Windows.Shapes.Line.X1Property, b);

绑定不工作...（WPF）“x：名称”问题？

3 个答案: