ControlTemplate in WPF —— ItemsControl

<ItemsControl Margin="10"              ItemsSource="{Binding Source={StaticResource myTodoList}}">  <!--The ItemsControl has no default visual appearance.      Use the Template property to specify a ControlTemplate to define      the appearance of an ItemsControl. The ItemsPresenter uses the specified      ItemsPanelTemplate (see below) to layout the items. If an      ItemsPanelTemplate is not specified, the default is used. (For ItemsControl,      the default is an ItemsPanelTemplate that specifies a StackPanel.-->  <ItemsControl.Template>    <ControlTemplate TargetType="ItemsControl">      <Border BorderBrush="Aqua" BorderThickness="1" CornerRadius="15">        <ItemsPresenter/>      </Border>    </ControlTemplate>  </ItemsControl.Template>  <!--Use the ItemsPanel property to specify an ItemsPanelTemplate      that defines the panel that is used to hold the generated items.      In other words, use this property if you want to affect      how the items are laid out.-->  <ItemsControl.ItemsPanel>    <ItemsPanelTemplate>      <WrapPanel />    </ItemsPanelTemplate>  </ItemsControl.ItemsPanel>  <!--Use the ItemTemplate to set a DataTemplate to define      the visualization of the data objects. This DataTemplate      specifies that each data object appears with the Proriity      and TaskName on top of a silver ellipse.-->  <ItemsControl.ItemTemplate>    <DataTemplate>      <DataTemplate.Resources>        <Style TargetType="TextBlock">          <Setter Property="FontSize" Value="18"/>          <Setter Property="HorizontalAlignment" Value="Center"/>        </Style>      </DataTemplate.Resources>      <Grid>        <Ellipse Fill="Silver"/>        <StackPanel>          <TextBlock Margin="3,3,3,0"                     Text="{Binding Path=Priority}"/>          <TextBlock Margin="3,0,3,7"                     Text="{Binding Path=TaskName}"/>        </StackPanel>      </Grid>    </DataTemplate>  </ItemsControl.ItemTemplate>  <!--Use the ItemContainerStyle property to specify the appearance      of the element that contains the data. This ItemContainerStyle      gives each item container a margin and a width. There is also      a trigger that sets a tooltip that shows the description of      the data object when the mouse hovers over the item container.-->  <ItemsControl.ItemContainerStyle>    <Style>      <Setter Property="Control.Width" Value="100"/>      <Setter Property="Control.Margin" Value="5"/>      <Style.Triggers>        <Trigger Property="Control.IsMouseOver" Value="True">          <Setter Property="Control.ToolTip"                  Value="{Binding RelativeSource={x:Static RelativeSource.Self},                          Path=Content.Description}"/>        </Trigger>      </Style.Triggers>    </Style>  </ItemsControl.ItemContainerStyle></ItemsControl>