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Ok i have an WPF application in wich i create my own ListBoxItem in a resource dictionary that looks like this :

    <DataTemplate x:Key="StationItem">
    <Grid x:Name="Gridder" Tag="{Binding SItem.StationName}" Width="125" Height="55">
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="20"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="20"/>
        </Grid.ColumnDefinitions>
        <Rectangle x:Name="Rectagler" Width="120" Height="50" RadiusX="5" RadiusY="5" VerticalAlignment="Center" HorizontalAlignment="Center" Grid.ColumnSpan="2" Grid.RowSpan="2" StrokeThickness="1" Stroke="Black">
            <Rectangle.Fill>
                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                    <GradientStop Color="#FFFF3A00" Offset="0"/>
                    <GradientStop Color="#FFE88D20" Offset="1"/>
                </LinearGradientBrush>
            </Rectangle.Fill>
        </Rectangle>
        <TextBlock Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="2" x:Name="StationName" Text="{Binding SItem.StationName}" Foreground="Black" FontSize="14" FontWeight="SemiBold" TextWrapping="NoWrap" VerticalAlignment="Center" HorizontalAlignment="Left" Margin="10,0,0,0"/>
        <TextBlock Grid.Column="0" Grid.Row="1" x:Name="StationCountry" Text="{Binding SItem.StationCountry}" Foreground="WhiteSmoke" FontSize="11" FontWeight="Light" TextWrapping="NoWrap" VerticalAlignment="Center" HorizontalAlignment="Left" Margin="10,0,0,8"/>
        <Image Tag="{Binding SItem.StationName}" Width="15" Height="15" RenderOptions.BitmapScalingMode="HighQuality" Grid.Column="1" Grid.Row="1" Source="{Binding FavSource}" VerticalAlignment="Center" HorizontalAlignment="Center" Margin="0,0,10,10"/>
    </Grid>
    <DataTemplate.Triggers>
        <Trigger Property="IsMouseOver" Value="true">
            <Setter TargetName="Rectagler" Property="Width" Value="125"/>
            <Setter TargetName="Rectagler" Property="Height" Value="55"/>
            <Setter TargetName="StationName" Property="Foreground" Value="White"/>
        </Trigger>
    </DataTemplate.Triggers>
</DataTemplate>

A ListBox like this : 

        <ListBox x:Name="StationsListLB" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="5" ItemTemplate="{DynamicResource GenreStyle}" ItemContainerStyle="{DynamicResource ContainerStyle}" Background="{x:Null}" BorderBrush="{x:Null}" PreviewMouseLeftButtonDown="StationsListLB_PreviewMouseLeftButtonDown" ScrollViewer.HorizontalScrollBarVisibility="Auto" ScrollViewer.VerticalScrollBarVisibility="Disabled" PreviewMouseDoubleClick="StationsListLB_PreviewMouseDoubleClick">
        <ListBox.ItemsPanel>
            <ItemsPanelTemplate>
                <WrapPanel IsItemsHost="True" Orientation="Vertical" MaxHeight="220" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ScrollViewer.VerticalScrollBarVisibility="Disabled" HorizontalAlignment="Center" VerticalAlignment="Center"/>
            </ItemsPanelTemplate>
        </ListBox.ItemsPanel>
    </ListBox>

And i populate my ListBox items when the user chooses an Genre of the station, with a method like this :

 public class Stations
{
    public StationItem SItem { get; set; }
    public string FavSource { get; set; }
}

public class StationItem
{
    public string StationName { get; set; }
    public string StationUrl { get; set; }
    public string StationGenre { get; set; }
    public string StationWebsite { get; set; }
    public string StationCountry { get; set; }
}

    private void LoadStationByGenre(string Genre)
    {
        StationsListLB.Items.Clear();
        StationsListLB.ItemTemplate = (DataTemplate)FindResource("StationItem");

        IEnumerable<Stations> results = StationList.Where(s => s.SItem.StationGenre.Equals(Genre));

        foreach (var Station in results)
        {
            StationsListLB.Items.Add(Station);
        }
    }

Note : Every StationGenre will populate my ListBox with at least 1000 StationItems.

My code works fine and starts with a memory of 40MB (Window Task Manager). But whenever i select a genre and populate my ListBox, memory explodes at 100MB.And i then select another genre memory explodes further. I thought that with ListBox.Items.Clear(); the ListBoxItems will be destroyed from memory too, but this doesnt happen.

I tried to remove the image from my ListoBoxItemTemplate and checked my app's memory, but didnt see a real difference (About 4-7 MB's difference).

So my answer is : How can i make my application consume a lot less memory when adding items in the ListBox?

Thanks in advance!!

4

1 回答 1

2

尝试使用VirtualizingStackPanel.VirtualizationMode="Recycling"以提高性能。引用MSDN：

默认情况下，VirtualizingStackPanel 为每个可见项目创建一个项目容器，并在不再需要它时将其丢弃（例如当项目滚动到视图之外时）。当 ItemsControl 包含大量项目时，创建和丢弃项目容器的过程会对性能产生负面影响。当 VirtualizingStackPanel.VirtualizationMode 设置为 Recycling 时，VirtualizingStackPanel 会重复使用项目容器，而不是每次都创建一个新容器。

于 2013-08-11T15:48:11.593 回答