Question

我对此非常陌生。我正在尝试在WPF中创建一个自定义控件，它将在其下方显示图像和一段文本。我从url下载图像作为BitmapImage类型。我有一个在我的UI上测试它正确下载它是。它下载并显示在，但在自定义控件中，Icon依赖属性只显示URL（我假设它是它看到的ToString（））。

这就是LEFT上功能框的外观，我用它来确认图像是否正确进入，以及右侧出现故障的GameIconControl：

http://i.imgur.com/heLcUMc.png

以下是控件的Generic.xaml

<Style TargetType="{x:Type assets:GameIconControl}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type assets:GameIconControl}">
                <Border Background="Transparent"
                        BorderBrush="{TemplateBinding BorderBrush}"
                        BorderThickness="{TemplateBinding BorderThickness}">
                    <StackPanel HorizontalAlignment="Center"
                                VerticalAlignment="Center"
                                Orientation="Vertical">

                            <ContentPresenter Height="Auto"
                                              Margin="3"
                                              ContentSource="Icon"
                                              HorizontalAlignment="Center"/>
                            <ContentPresenter Height="Auto"
                                              Margin="3"
                                              ContentSource="GameName"
                                              HorizontalAlignment="Center"/>
                    </StackPanel>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

这是GameIconControl.cs中的C＃

public class GameIconControl : Control
{
    static GameIconControl()
    {
        DefaultStyleKeyProperty.OverrideMetadata(typeof(GameIconControl), new FrameworkPropertyMetadata(typeof(GameIconControl)));
    }

    public GameIconControl(){}

    public GameIconControl(string name, BitmapImage icon)
    {
        Icon = icon;
        GameName = name;
    }

    public const string IconPropertyName = "Icon";
    public const string GameNamePropertyName = "GameName";

    public string GameName
    {
        get { return (string)GetValue(GameNameProperty); }
        set { SetValue(GameNameProperty, value); }
    }


    public static readonly DependencyProperty GameNameProperty =
        DependencyProperty.Register(GameNamePropertyName, typeof(string), typeof(GameIconControl), new UIPropertyMetadata(default(string)));



    public BitmapImage Icon
    {
        get { return (BitmapImage)GetValue(IconProperty); }
        set { SetValue(IconProperty, value); }
    }

    public static readonly DependencyProperty IconProperty =
        DependencyProperty.Register(IconPropertyName, typeof(BitmapImage), typeof(GameIconControl), new PropertyMetadata(default(BitmapImage)));



}

我错过了什么？

Answer 1

我建议使用Image来展示Icon属性，而不是ContentPresenter。将Icon属性绑定到Image.Source，它应该可以正常工作。

Answer 2

您应该只能使用ImageSource属性绑定到Image.Source属性来显示它：

public ImageSource Icon
{
    get { return (ImageSource)GetValue(IconProperty); }
    set { SetValue(IconProperty, value); }
}

public static readonly DependencyProperty IconProperty =
    DependencyProperty.Register(IconPropertyName, typeof(ImageSource), 
    typeof(GameIconControl), new PropertyMetadata(null));

...

Icon = new BitmapImage(new Uri("C:\\Image.jpg"));

...

<Image Source="{TemplateBinding Icon}" />

虽然，如果您只是想显示图片，甚至不需要使用ImageSource数据类型......您只需使用string路径：

Icon = "C:\\Image.jpg";

or

Icon = "/YourAppName;component/ImageFolderName/ImageName.jpg";

...

<Image Source="{TemplateBinding Icon}" />

如何使用ContentPresenter在自定义控件中显示BitmapImage？

2 个答案: