我正在开发一个avaloniawpf应用程序,并且我注册了一个AttachedProperty"IsFocused";如下所示:
public class FocusExtension
{
public static readonly AttachedProperty<bool> IsFocusedProperty =
AvaloniaProperty.RegisterAttached<Control, bool>("IsFocused", typeof(FocusExtension));
public static bool GetIsFocused(Control element)
{
return element.GetValue(IsFocusedProperty);
}
public static void SetIsFocused(Control element, bool value)
{
element.SetValue(IsFocusedProperty, value);
OnIsFocusedPropertyChanged(element, value);
}
private static void OnIsFocusedPropertyChanged(
Control element,
bool e)
{
if (e)
{
element.Focus();
}
}
}
并将其应用于xaml中,如下所示:
<Button Content="Test" u:FocusExtension.IsFocused="{Binding SomeBoolPropertyInViewModel}"/>
但当";SomeBoolPropertyInViewModel";在我的ViewModel,中设置为true
有人能给我一个例子或提示来实现这项工作吗?谢谢
不能保证SetIsFocused
会被调用,因为element.SetValue(IsFocusedProperty, value)
可能会被直接调用。因此,您必须在静态构造函数中为属性更改事件添加一个处理程序:
static FocusExtension()
{
IsFocusedProperty.Changed.AddClassHandler<Control>(OnIsFocusedPropertyChanged);
}
private static void OnIsFocusedPropertyChanged(
Control element,
AvaloniaPropertyChangedEventArgs e)
{
if ((bool)e.NewValue)
{
element.Focus();
}
}