这是以下问题：Items added to ItemsControl not using ItemTemplate
我有2个类应该处理对象的移动和调整大小（MoveThumb和ResizeThumb）。模板正在应用于ItemsControl中的对象，并且应该转换对象的函数被触发但我无法使其工作。
ItemsControl绑定到'{1}}'DashboardItems'，此时只是返回ObservableCollection的X和Y的简单对象。我可能会在将来添加它们，但我希望首先使用基础知识
在Canvas.SetTop/Left'项目中的比较'始终为空。 MoveThumb_DragDelta有同样的问题。
发件人是ResizeThumb，MoveThumb是sender.DataContext
我的问题是：我应该如何正确设置模板和/或类的数据上下文，以便ContentPresenter可以获得触发它的控件？
编辑：
将MoveThumb_DragDelta更改为Control item = this.DataContext as Control;已使运动正常，但调整大小不起作用，因为UIElement不包含ActualHeight / Width或MinHeight / Width。
UIElement item = this.DataContext as UIElement;：
MoveThumb public class MoveThumb : Thumb
{
public MoveThumb()
{
DragDelta += new DragDeltaEventHandler(this.MoveThumb_DragDelta);
}
private void MoveThumb_DragDelta(object sender, DragDeltaEventArgs e)
{
Control item = this.DataContext as Control;
if (item != null)
{
double left = Canvas.GetLeft(item);
double top = Canvas.GetTop(item);
Canvas.SetLeft(item, left + e.HorizontalChange);
Canvas.SetTop(item, top + e.VerticalChange);
}
}
}
：
MainWindow.xaml
<Window.Resources>
<ControlTemplate x:Key="MoveThumbTemplate" TargetType="{x:Type local:MoveThumb}">
<Rectangle Fill="Transparent"/>
</ControlTemplate>
<ControlTemplate x:Key="ResizeDecoratorTemplate" TargetType="Control">
<Grid>
<local:ResizeThumb Height="2" Cursor="SizeNS" Margin="0 -4 0 0" VerticalAlignment="Top" HorizontalAlignment="Stretch"/>
<local:ResizeThumb Width="2" Cursor="SizeWE" Margin="-4 0 0 0" VerticalAlignment="Stretch" HorizontalAlignment="Left"/>
<local:ResizeThumb Width="2" Cursor="SizeWE" Margin="0 0 -4 0" VerticalAlignment="Stretch" HorizontalAlignment="Right"/>
<local:ResizeThumb Height="2" Cursor="SizeNS" Margin="0 0 0 -4" VerticalAlignment="Bottom" HorizontalAlignment="Stretch"/>
<local:ResizeThumb Width="7" Height="7" Cursor="SizeNWSE" Margin="-6 -6 0 0" VerticalAlignment="Top" HorizontalAlignment="Left"/>
<local:ResizeThumb Width="7" Height="7" Cursor="SizeNESW" Margin="0 -6 -6 0" VerticalAlignment="Top" HorizontalAlignment="Right"/>
<local:ResizeThumb Width="7" Height="7" Cursor="SizeNESW" Margin="-6 0 0 -6" VerticalAlignment="Bottom" HorizontalAlignment="Left"/>
<local:ResizeThumb Width="7" Height="7" Cursor="SizeNWSE" Margin="0 0 -6 -6" VerticalAlignment="Bottom" HorizontalAlignment="Right"/>
</Grid>
</ControlTemplate>
<DataTemplate DataType="{x:Type local:TableControl}">
<Grid DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}">
<local:MoveThumb Template="{StaticResource MoveThumbTemplate}" DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}" Cursor="SizeAll"/>
<Control Template="{StaticResource ResizeDecoratorTemplate}"/>
<Button Content="x" VerticalAlignment="Top" HorizontalAlignment="Right" Width="10" Height="10" Click="Button_Click"/>
<Ellipse Fill="Red" IsHitTestVisible="False" Height="100" Width="100"/>
</Grid>
</DataTemplate>
<DataTemplate DataType="{x:Type local:GraphControl}">
<Grid DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}">
<local:MoveThumb Template="{StaticResource MoveThumbTemplate}" DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}" Cursor="SizeAll"/>
<Control Template="{StaticResource ResizeDecoratorTemplate}"/>
<Button Content="x" VerticalAlignment="Top" HorizontalAlignment="Right" Width="10" Height="10" Click="Button_Click"/>
<Ellipse Fill="Green" IsHitTestVisible="False" Height="100" Width="100"/>
</Grid>
</DataTemplate>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<ribbon:Ribbon Margin="0,-22,0,0" Grid.Row="0">
<ribbon:RibbonTab Header="Dashboard">
<ribbon:RibbonGroup Header="Customise">
<ribbon:RibbonMenuButton Label="New" FontSize="20" Height="60" Width="60">
<ribbon:RibbonMenuItem Header="Graph" Click="NewGraph"/>
<ribbon:RibbonMenuItem Header="Table" Click="NewTable"/>
</ribbon:RibbonMenuButton>
</ribbon:RibbonGroup>
</ribbon:RibbonTab>
</ribbon:Ribbon>
<ItemsControl Name="dashboardControls" ItemsSource="{Binding Path=CanvasContents}" Grid.Row="1">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<Canvas/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemContainerStyle>
<Style>
<Setter Property="Canvas.Top" Value="{Binding Path=Y}"/>
<Setter Property="Canvas.Left" Value="{Binding Path=X}"/>
</Style>
</ItemsControl.ItemContainerStyle>
</ItemsControl>
</Grid>
：
MainWindow.xaml.cs public partial class MainWindow : Window
{
public static Dashboard dashboard;
public MainWindow()
{
dashboard = new Dashboard();
InitializeComponent();
this.DataContext = dashboard;
}
private void NewGraph(object sender, RoutedEventArgs e)
{
dashboard.CanvasContents.Add(new GraphControl());
}
private void NewTable(object sender, RoutedEventArgs e)
{
dashboard.CanvasContents.Add(new TableControl());
}
}
：
Dashboard.cs public class Dashboard: INotifyPropertyChanged
{
ObservableCollection<DashboardItem> _canvasContents;
public Dashboard()
{
_canvasContents = new ObservableCollection<DashboardItem>();
}
public ObservableCollection<DashboardItem> CanvasContents
{
get { return _canvasContents; }
}
}
：
DashboardItem.cs答案 0 :(得分：0)
我还没有尝试过，但http://www.codeproject.com/Articles/22952/WPF-Diagram-Designer-Part似乎有可能找到答案。
编辑：
我从评论中看到，问题在于从Canvas转移到ItemsControl。在该上下文中似乎存在Canvas.Top和Canvas.Left的问题，以及设置某些样式属性的解决方案：Dragable objects in WPF in an ItemsControl?