这是此处问题的延续:尝试设置自定义 DependencyObject。显然漏掉了什么。编辑原始问题是不切实际的;变化太大。所以我开始一个新的问题。
我正在尝试在我的 UWP 应用程序中设置自定义 DependencyObjects 之间的绑定。相关代码如下。我看到对 ActualWidthPropertyChanged 的调用,但它们没有触发对 WidthPropertyChanged 的任何调用。我错过了什么?
class WindowsElement: DependencyObject
{
public WindowsElement()
{
}
public double Width
{
get
{
return (double)GetValue(WidthProperty);
}
set
{
SetValue(WidthProperty, value);
}
}
private static void WidthPropertyChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
{
WindowsElement element = (WindowsElement)o;
double width = (double)e.NewValue;
CommonDebug.LogLine("WPC", element, o, width);
element.Width = width;
}
private static void ActualWidthPropertyChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
{
WindowsElement element = (WindowsElement)o;
double width = (double)e.NewValue;
CommonDebug.LogLine("AWPC", o, e, width, element.Width);
element.ActualWidth = width;
}
public static readonly DependencyProperty WidthProperty = DependencyProperty.Register(
"Width",
typeof(double),
typeof(WindowsElement),
new PropertyMetadata((double)0, WidthPropertyChanged));
public double ActualWidth {
get
{
return (double)GetValue(ActualWidthProperty);
}
set
{
SetValue(ActualWidthProperty, value);
}
}
public static readonly DependencyProperty ActualWidthProperty =
DependencyProperty.Register(
"ActualWidth",
typeof(double),
typeof(WindowsElement),
new PropertyMetadata((double)0, ActualWidthPropertyChanged));
public static void MessWithBindings()
{
WindowsElement we1 = new WindowsElement();
WindowsElement we2 = new WindowsElement();
var b = new Binding
{
Source = we2,
Path = new PropertyPath("ActualWidth")
};
BindingOperations.SetBinding(we1, WindowsElement.WidthProperty, b);
we2.ActualWidth = 13;
CommonDebug.LogLine(we1, we1.Width, we1.ActualWidth, we2, we2.Width, we2.ActualWidth);
}
}