0

我在一个简单的 WinRT 演示项目中有两个非常简单的 UserControl。没有 Viewmodel——主要是用于布局探索的彩色框。我创建的第一个 UserControl 工作正常。第二个，非常相似，不会绑定到任何属性——它显示为空白。

第一个 UserControl 如下所示：

    <UserControl
    x:Class="Demo.SmallStartTile"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:Demo"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    x:Name="SmallStartTileUC"
    d:DesignHeight="300"
    d:DesignWidth="400">


    <Grid x:Name="SmallTileGrid"
        Margin="0,0,8,8"
        Background="{Binding Background, ElementName=SmallStartTileUC}"
        >

        <Rectangle
            Stroke="{Binding BorderBrush, ElementName=SmallStartTileUC}"
            Grid.RowSpan="2"
            />

        <TextBlock x:Name="SmallTileTitle" 
            Text="{Binding TileText, ElementName=SmallStartTileUC}" 
            Style="{StaticResource SmallTileHeader}"/>

        <Path x:Name="IconPath" 
            Style="{StaticResource SmallTileIcon}" 
            Data="{Binding TileIconPathData, ElementName=SmallStartTileUC}" />

    </Grid>




    </UserControl>

namespace Demo
{
    public sealed partial class SmallStartTile : UserControl
    {
    public static DependencyProperty TileTextProperty = DependencyProperty.Register("TileText", typeof(string), typeof(SmallStartTile), new PropertyMetadata("tile content"));

    public string TileText
    {
        get { return (string)GetValue(TileTextProperty); }
        set { SetValue(TileTextProperty, value); }
    }


    public static DependencyProperty TileIconPathDataProperty = DependencyProperty.Register("TileIconPathData", typeof(string), typeof(SmallStartTile), new PropertyMetadata("F0"));

    public string TileIconPathData
    {
        get { return (string)GetValue(TileIconPathDataProperty); }
        set { SetValue(TileIconPathDataProperty, value); }
    }



    public SmallStartTile()
    {
        this.InitializeComponent();
    }
}

}

第二个，就像第一个一样，通过单击 Add New Item 并在 Blend 中选择 UserControl：

<UserControl
x:Class="Demo.SmallMediaTile"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:Demo"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Name="SmallMediaTileUC"
d:DesignHeight="300"
d:DesignWidth="400">

<Grid 
    Margin="0,0,8,8"
    Background="{Binding Background, ElementName=SmallMediaTileUC}"
    >

    <Grid.RowDefinitions>
        <RowDefinition/>
        <RowDefinition Height="Auto"/>
    </Grid.RowDefinitions>

    <Rectangle 
        Stroke="{Binding BorderBrush, ElementName=SmallMediaTileUC}"
        Grid.RowSpan="2"
        />

    <Viewbox 
        Margin="30" 
        Child="{Binding Content, ElementName=SmallMediaTileUC}">
    </Viewbox>

    <TextBlock 
        Grid.Row="1" 
        Text="{Binding SourceText, ElementName=SmallMediaTileUC}" 
        Style="{StaticResource SmallMusicTileHeader}"/>

</Grid>

</UserControl>


namespace Demo
{
    public sealed partial class SmallMediaTile : UserControl
    {

    public static DependencyProperty SourceTextProperty = DependencyProperty.Register("SourceText", typeof(string), typeof(SmallMediaTile), new PropertyMetadata("source"));

    public string SourceText
    {
        get { return (string)GetValue(SourceTextProperty); }
        set { SetValue(SourceTextProperty, value); }
    }



    public SmallMediaTile()
    {
        this.InitializeComponent();
    }
}

}

我在主页中使用 UserControl，如下所示：

                            <local:SmallMediaTile x:Name="Source1Tile"
                            Grid.Column="0" Grid.Row="0"
                            SourceText="Radio"
                            Background="Blue"
                            BorderBrush="Red">
                            <local:SmallMediaTile.Content>
                            <Canvas x:Name="radio_icon" Height="68" Width="34">
                                <Path Data="F1M299.6182,396.2988C299.6182,389.7208,297.0722,383.5548,292.4572,378.8398L288.6162,382.6758C292.2022,386.3718,294.1842,391.1778,294.1842,396.2988C294.1842,401.4238,292.2022,406.2368,288.6162,409.9328L292.4572,413.7738C297.0722,409.0538,299.6182,402.8808,299.6182,396.2988" Fill="White" Height="34.934" Canvas.Left="0" Stretch="Fill" Canvas.Top="16.501" Width="11.002"/>
                                <Path Data="F1M311.1738,396.2988C311.1738,386.6278,307.4348,377.5528,300.6788,370.6208L296.8258,374.4618C302.5658,380.3698,305.7398,388.0798,305.7398,396.2988C305.7398,404.5218,302.5658,412.2298,296.8258,418.1428L300.6788,421.9898C307.4348,415.0498,311.1738,405.9718,311.1738,396.2988" Fill="White" Height="51.369" Canvas.Left="8.21" Stretch="Fill" Canvas.Top="8.282" Width="14.348"/>
                                <Path Data="F1M322.7578,396.2988C322.7578,383.5298,317.8508,371.5348,308.9638,362.3388L305.1168,366.1748C312.9758,374.3538,317.3338,384.9778,317.3338,396.2988C317.3338,407.6208,312.9758,418.2488,305.1168,426.4268L308.9638,430.2748C317.8508,421.0698,322.7578,409.0798,322.7578,396.2988" Fill="White" Height="67.936" Canvas.Left="16.501" Stretch="Fill" Canvas.Top="0" Width="17.641"/>
                            </Canvas>
                            </local:SmallMediaTile.Content>
                        </local:SmallMediaTile>

第一个像我期望的那样拾取所有属性和显示，但第二个只拾取 Viewbox 内容。我已经查看了 SO 并一直在谷歌搜索，但无法弄清楚问题所在。对不起，如果这是冗长的。

4

2 回答 2

0

当你试图将其属性绑定到它的上层时，你的根Grid被设置为Content那个。这是不允许的，因为根已经是 的父级，并且 XAML 控件只能存在于 UI 中的一个位置。UserControlViewboxChildContentUserControlGridUserControl

于 2013-02-07T19:01:58.107 回答
0

如前所述，问题是 UserControl 的内容只能设置一次。当我将 Viewbox 内容绑定到 UserControl 内容时，现有的 XAML 将被替换。因此，一个空白框，但对于我传入的内容。我想要做我希望的事情，我需要制作一个自定义控件。谢谢您的帮助！

于 2013-02-15T00:08:11.800 回答