ListView不显示图像在WPF

Question

我是wpf的新手。我创建了listview以统一显示图像。我做了一个转换器类，将byte []转换为位图图像。在这里，图像是从数据库动态加载的。加载listview时，不显示任何内容。我已附上我的源代码。

这是我的xaml代码：                                                                                                                                                                                                                                  

                        <DataTemplate>
                            <StackPanel Orientation="Horizontal">
                                <TextBlock Text="{Binding price}"  />

                                <Image Source="{Binding Path=ImageFile,RelativeSource={RelativeSource AncestorType=ListView} 
                                    ,Converter={StaticResource ImageConverter}}" Height="300" Width="300" />
                            </StackPanel>
                        </DataTemplate>
                    </ListView.ItemTemplate>
                    <ListBox.ItemsPanel>
                        <ItemsPanelTemplate>
                            <UniformGrid Columns="5" HorizontalAlignment="Stretch"/>
                        </ItemsPanelTemplate>
                    </ListBox.ItemsPanel>
                </ListView>

这是我的转换器类代码：

     public sealed class ImageConverter : IValueConverter
        {
            public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
            {
                try
                {
                    return new BitmapImage(new Uri((string)value));
                }
                catch
                {
                    return new BitmapImage();
                }
            }

            public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
            {
                throw new NotImplementedException();
            }

这是列表框绑定代码：

 private void clickme_Click(object sender, RoutedEventArgs e)
        {

            string connection = ConfigurationManager.ConnectionStrings["POSconnection"].ConnectionString;
            SqlConnection con = new SqlConnection(connection);

            SqlCommand cmd = new SqlCommand("SP_Getsubitem", con);
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.AddWithValue("@getname","Pasta");
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataTable dt = new DataTable();
            DataSet ds = new DataSet();
            da.Fill(dt);
            getdatas.ItemsSource = dt.DefaultView;

        }