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我試圖顯示列表框中嵌入我的asssembly中的圖像。我可以使用轉換器將圖像顯示出來，但不是加載，而是靜止不動，它們不斷從組件中重新加載，導致它們閃爍。我使用相同的轉換器來加載我的應用程序周圍的其他地方的圖標，但這個問題不會發生 - 它似乎是以某種方式由lisbox造成的。我嘗試刪除VisualStates並切換轉換器返回的位圖圖像的CreateOption，但我得到相同的結果。我相當確信這在WP7.0上沒有發生，只有7.1。圖像在WP7中閃爍ListBox
的風格是：
<Style x:Key="SnapshotList" TargetType="ListBox">
<Setter Property="Margin" Value="2" />
<Setter Property="BorderThickness" Value="1"/>
<!--<Setter Property="Background" Value="{StaticResource WindowBackgroundBrush}" />
<Setter Property="BorderBrush" Value="{StaticResource PhoneBorderBrush}" />-->
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<!--Setter Property="OverridesDefaultStyle" Value="True"/-->
<Setter Property="ItemTemplate" Value="{StaticResource SnapshotTemplate}"/>
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<Controls:WrapPanel HorizontalAlignment="Stretch" VerticalAlignment="Top"/>
<!--<WP7:BindingHelper.Binding>
<WP7:RelativeSourceBinding Path="(FrameworkElement.ActualWidth)" TargetProperty="Width"
RelativeMode="FindAncestor"
AncestorType="ScrollContentPresenter" />
</WP7:BindingHelper.Binding>-->
<!--</Controls:WrapPanel>-->
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBox">
<Border Name="Border" Background="{TemplateBinding Background}" BorderThickness="{TemplateBinding BorderThickness}"
BorderBrush="{StaticResource PhoneBorderBrush}" CornerRadius="2">
<ScrollViewer Margin="0">
<ItemsPresenter/>
</ScrollViewer>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
有問題的列表框：
<ListBox x:Name="lstIcon" ItemsSource="{Binding AvailableIcons}" SelectedItem="{Binding Recipe.Icon,Mode=TwoWay}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" SelectionMode="Single"
Style="{StaticResource SnapshotList}">
<ListBox.ItemTemplate>
<DataTemplate>
<Border Background="Transparent" MinWidth="30" MinHeight="30" Margin="3" Padding="3">
<Image Source="{Binding Converter={StaticResource IconConverter}, ConverterParameter=32}" Stretch="None" MinWidth="30" MinHeight="30" />
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
轉換器：
public class IconConverter : IValueConverter
{
private static IEnumerable<string> _names;
private static IEnumerable<string> ResourceNames {
get {
if (_names == null) {
_names = WP7Utils.GetResourcePaths(Assembly.GetExecutingAssembly()).Select(p=>System.Convert.ToString(p)).ToList();
}
return _names;
}
}
public object Convert(object value, Type targetType, object parameter, CultureInfo culture) {
string baseFilename = (value ?? Shared.Constants.DefaultIcon).ToString().Trim();
string size = (parameter ?? "32").ToString();
try {
BitmapImage img = new BitmapImage();
using (var store = IsolatedStorageFile.GetUserStoreForApplication()) {
string fileName = string.Format("{0}_{1}.png", baseFilename, size);
img = ResourceHelper.GetBitmap("Resources/types/" + fileName, "MyAssembly");
}
return img;
} catch (Exception ex) {
Console.WriteLine(string.Format("Error loading image {0} ({1}px): {2}", baseFilename, size, ex.Message));
}
return value;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) {
throw new NotImplementedException();
}
}