Question

我正在尝试将设计数据显示在我的设计师预览中。运行程序时，UserControl正常运行；但是我无法让设计师使用值填充。

首先，我的UserControl名为SignalStrengthControl

<UserControl x:Class="Connection.SignalStrengthControl"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:Connection"
             mc:Ignorable="d" 
             d:DesignHeight="53.833" d:DesignWidth="100.917"
             d:DataContext="{d:DesignData Source=DesignData/SignalStrengthControlDesignData.xaml}">
    <Grid Background="Transparent">
        <Grid.Resources>
            <SolidColorBrush x:Key="OnColor" Color="#FF4a6bc8"></SolidColorBrush>
            <SolidColorBrush x:Key="OffColor" Color="#50FFFFFF"></SolidColorBrush>
            <local:RatingConverter x:Key="RatingConverter" OnBrush="{StaticResource OnColor}" OffBrush="{StaticResource OffColor}" />

            <Style TargetType="Rectangle">
                <Setter Property="VerticalAlignment" Value="Bottom" />
            </Style>
        </Grid.Resources>

        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="1*"></ColumnDefinition>
            <ColumnDefinition Width=".4*"></ColumnDefinition>
            <ColumnDefinition Width="1*"></ColumnDefinition>
            <ColumnDefinition Width=".4*"></ColumnDefinition>
            <ColumnDefinition Width="1*"></ColumnDefinition>
            <ColumnDefinition Width=".4*"></ColumnDefinition>
            <ColumnDefinition Width="1*"></ColumnDefinition>
            <ColumnDefinition Width=".4*"></ColumnDefinition>
            <ColumnDefinition Width="1*"></ColumnDefinition>
        </Grid.ColumnDefinitions>

        <Grid Grid.Column="0">
            <Grid.RowDefinitions>
                <RowDefinition Height="4*"></RowDefinition>
                <RowDefinition Height="1*"></RowDefinition>
            </Grid.RowDefinitions>
            <Rectangle Grid.Row="1"
                       Fill="{Binding Path=RatingValue, ConverterParameter=1, Converter={StaticResource RatingConverter}, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:SignalStrengthControl}}}"
                       Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"
                       Height="{Binding ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"/>
        </Grid>

        <Grid Grid.Column="2">
            <Grid.RowDefinitions>
                <RowDefinition Height="3*"></RowDefinition>
                <RowDefinition Height="2*"></RowDefinition>
            </Grid.RowDefinitions>
            <Rectangle Grid.Row="1"
                       Fill="{Binding Path=RatingValue, ConverterParameter=2, Converter={StaticResource RatingConverter}, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:SignalStrengthControl}}}"
                       Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"
                       Height="{Binding ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"/>
        </Grid>

        <Grid Grid.Column="4">
            <Grid.RowDefinitions>
                <RowDefinition Height="2*"></RowDefinition>
                <RowDefinition Height="3*"></RowDefinition>
            </Grid.RowDefinitions>
            <Rectangle Grid.Row="1"
                       Fill="{Binding Path=RatingValue, ConverterParameter=3, Converter={StaticResource RatingConverter}, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:SignalStrengthControl}}}"
                       Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"
                       Height="{Binding ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"/>
        </Grid>

        <Grid Grid.Column="6">
            <Grid.RowDefinitions>
                <RowDefinition Height="1*"></RowDefinition>
                <RowDefinition Height="4*"></RowDefinition>
            </Grid.RowDefinitions>
            <Rectangle Grid.Row="1"
                       Fill="{Binding Path=RatingValue, ConverterParameter=4, Converter={StaticResource RatingConverter}, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:SignalStrengthControl}}}"
                       Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"
                       Height="{Binding ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"/>
        </Grid>

        <Grid Grid.Column="8">
            <Grid.RowDefinitions>
                <RowDefinition Height="0*"></RowDefinition>
                <RowDefinition Height="5*"></RowDefinition>
            </Grid.RowDefinitions>
            <Rectangle Grid.Row="1"
                       Fill="{Binding Path=RatingValue, ConverterParameter=5, Converter={StaticResource RatingConverter}, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:SignalStrengthControl}}}"
                       Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"
                       Height="{Binding ActualHeight, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Grid}}"/>
        </Grid>
    </Grid>
</UserControl>

您可以看到我有一个可忽略的DataContext，它指向一些设计数据（找到文件没有问题）。该UserControl背后的想法是，它包含一个枚举依赖项属性，并且具有一个枚举转换器，该转换器控制条形的填充，从而创建类似wifi信号强度指示器的内容。

<local:SignalStrengthControlDesignData
    xmlns:local="clr-namespace:Connection.DesignData"
    xmlns:connection="clr-namespace:Connection"
    xmlns:markup="http://schemas.microsoft.com/winfx/2006/xaml"
    RatingValue="FourBars"
/>
<!--RatingValue="{markup:Static connection:SignalStrength.FourBars}"-->

这是我的SignalStrengthControlDesignData.xaml。我尝试了注释掉的代码，它也不起作用。我相信“ FourBars”被解释为枚举，因为自动完成功能说它是枚举成员。下面是背后的设计数据代码。

internal sealed class SignalStrengthControlDesignData
{
    public SignalStrength RatingValue { get; set; }
}

以下是SignalStrengthControl的代码，具有依赖项属性，枚举和转换器。

public partial class SignalStrengthControl 
{
    public SignalStrengthControl()
    {
        InitializeComponent();
    }

    public SignalStrength RatingValue
    {
        get { return (SignalStrength)GetValue(RatingValueProperty); }
        set { SetValue(RatingValueProperty, value); }
    }

    // Using a DependencyProperty as the backing store for RatingValue.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty RatingValueProperty =
        DependencyProperty.Register("RatingValue", typeof(SignalStrength), typeof(SignalStrengthControl), new UIPropertyMetadata(SignalStrength.ZeroBars));
}

public enum SignalStrength
{
    ZeroBars,
    OneBar,
    TwoBars,
    ThreeBars,
    FourBars,
    FiveBars
}

public class RatingConverter : IValueConverter
{
    public Brush OnBrush { get; set; }
    public Brush OffBrush { get; set; }

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value == null || parameter == null)
        {
            return Brushes.Transparent;
        }

        // There are five bars in the xaml with each having a barNumber associated with it. The smallest bar
        // on the left has a barNumber value of 1, the largest has 5.
        int barNumber;
        if (int.TryParse(parameter.ToString(), out barNumber))
        {
            var signalStrengthRating = (int)value; 
            if (barNumber <= signalStrengthRating)
            {
                return this.OnBrush;
            }
            return this.OffBrush;
        }
        return Brushes.Transparent;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

我也已将this.OnBrush替换为Brushes.WhatColor，它仍然没有出现在设计器中。

我知道一种显示某种东西的方法是拥有一个FallBackValue，但是将来我可能需要比显示的更为复杂的东西。

打开所有建议。

Answer 1

我将实现更改为使用自定义控件，该控件将覆盖ProgressBar WPF控件。然后设计数据按预期显示。

使设计数据显示在设计器预览中的问题

1 个答案: