UWP Setter 自定义依赖项属性

Question

我有一个名为IconTextButton的自定义控件，它定义了一些属性。

public sealed partial class IconTextButton : UserControl
{
public string Label
{
get => (string)GetValue(LabelProperty);
set => SetValue(LabelProperty, value);
}
public static readonly DependencyProperty LabelProperty = DependencyProperty.Register("Label",
                    typeof(string),
                    typeof(IconTextButton),
                    new PropertyMetadata(""));
public IconElement Icon { get; set; }
public IconTextButtonLabelPosition LabelPosition
{
get => (IconTextButtonLabelPosition)GetValue(LabelPositionProperty);
set
{
SetValue(LabelPositionProperty, value);
Grid.SetColumn(LabelTextBlock, value == IconTextButtonLabelPosition.Left ? 0 : 2);
}
}
public static readonly DependencyProperty LabelPositionProperty = DependencyProperty.Register("LabelPosition", 
                            typeof(IconTextButtonLabelPosition), 
                            typeof(IconTextButton), 
                            new PropertyMetadata(IconTextButtonLabelPosition.Left));
public Thickness IconTextMargin
{
get => (Thickness)GetValue(IconTextMarginProperty);
set => SetValue(IconTextMarginProperty, value);
}
public static readonly DependencyProperty IconTextMarginProperty = DependencyProperty.Register("IconTextMargin",
                             typeof(Thickness),
                             typeof(IconTextButton),
                             new PropertyMetadata(null));
public Brush IconBackground
{
get { return (Brush)GetValue(IconBackgroundProperty); }
set { SetValue(IconBackgroundProperty, value); }
}
public static readonly DependencyProperty IconBackgroundProperty = DependencyProperty.Register("IconBackground",
                    typeof(Brush),
                    typeof(IconTextButton),
                    new PropertyMetadata(null));
public double IconRadius
{
get => (double)GetValue(IconRadiusProperty);
set
{
SetValue(IconRadiusProperty, value);
IconBackgroundBorder.Width = value * 2;
IconBackgroundBorder.Height = value * 2;
IconBackgroundBorder.CornerRadius = new CornerRadius(value);
}
}
public static readonly DependencyProperty IconRadiusProperty = DependencyProperty.Register("IconRadius",
                    typeof(double),
                    typeof(IconTextButton),
                    new PropertyMetadata(15));
}

我想根据其视觉状态更改其属性，但它没有改变。为什么？

<VisualState.Setters>
<Setter Target="LocalShuffleItem.Label" Value="" />
<Setter Target="LocalListViewItem.Label" Value="" />
<Setter Target="LocalGridViewItem.Label" Value="" />
<Setter Target="LocalShuffleItem.IconTextMargin" Value="0" />
<Setter Target="LocalListViewItem.IconTextMargin" Value="0" />
<Setter Target="LocalGridViewItem.IconTextMargin" Value="0" />
</VisualState.Setters>

Answer 1

问题是 Label 和 IconTextMargin 不是代码中的依赖属性。

问题是默认x:Bind模型是OneTime.当您在VisualState中编辑其值时，属性的值不会更改。请检查IconTextButton类并更改x:Bind模式OneWay。

<TextBlock
x:Name="LabelTextBlock"
Grid.Column="2"
Margin="{x:Bind IconTextMargin,Mode=OneWay}"
VerticalAlignment="Center"
AutomationProperties.AccessibilityView="Raw"
FontSize="{x:Bind FontSize}"
FontWeight="{x:Bind FontWeight}"
Foreground="{x:Bind Foreground}"
Text="{x:Bind Label, Mode=OneWay}"
TextAlignment="Center"
TextWrapping="Wrap" />