未显示图像（位图）的 WPF 绑定到转换器
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WPF Binding to converter for an Image (Bitmap) not showing
提问by asuppa
I am having issues with an image not showing in a WPF control using a Converter to create the image from a local directory. Any direction on what I am doing wrong would be appreciated.
我在使用转换器从本地目录创建图像的 WPF 控件中未显示图像时遇到问题。任何关于我做错了什么的方向将不胜感激。
XAML
XAML
<UserControl x:Class="Coms.Views.ImageDetailView"
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:c="clr-namespace:Coms.Converter"
mc:Ignorable="d"
d:DesignHeight="100" d:DesignWidth="300" Background="Wheat">
<Control.Resources>
<c:ImageDetailConverter x:Key="converter" />
</Control.Resources>
<ListBox ItemsSource="{Binding icList}" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ScrollViewer.VerticalScrollBarVisibility="Auto">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="200"/>
</Grid.ColumnDefinitions>
<Image Name="imgBox" Width="auto" Height="auto" Grid.Column="0" Source="{Binding Converter={StaticResource converter}}" />
<TextBlock Name="txtBlock2" Grid.Column="1" Text="{Binding coordinates}"/>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
class
班级
public class ImageDetail
{
public string fileName { get; set; }
public string coordinates { get; set; }
}
Converter
转换器
public class ImageDetailConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
IRuntimeConfigurations configs = ServiceLocator.Current.GetInstance<IRuntimeConfigurations>();
return new Bitmap(Image.FromFile(Path.Combine(configs.rootImagePath, ((IImageDetail)value).fileName)));
}
}
回答by Clemens
Your converter returns a System.Drawing.Bitmap, which is WinForms, not WPF.
您的转换器返回一个System.Drawing.Bitmap，它是 WinForms，而不是 WPF。
It should return a WPF ImageSource(e.g. a BitmapImage) instead:
它应该返回一个 WPF ImageSource（例如 a BitmapImage）：
public object Convert(
object value, Type targetType, object parameter, CultureInfo culture)
{
var imageDetail = (ImageDetail)value;
var configs = ServiceLocator.Current.GetInstance<IRuntimeConfigurations>();
var path = Path.Combine(configs.rootImagePath, imageDetail.fileName);
var uri = new Uri(path, UriKind.RelativeOrAbsolute);
return new BitmapImage(uri);
}
Note also that WPF provides built-in type conversion from Uriand string(containing a valid URI) to ImageSource, so that your converter could also return the urior pathvalue.
另请注意，WPF 提供了从Uri和string（包含有效的 URI）到 的内置类型转换ImageSource，因此您的转换器也可以返回uri或path值。
