WPF Diagram Designer: Part 1

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:s="clr-namespace:DragAndResizeControl">

  <!-- DragThumb Template -->
  <ControlTemplate x:Key="DragThumbTemplate" TargetType="{x:Type s:DragThumb}">
    <Rectangle Fill="Transparent"/>
  </ControlTemplate>

  <!-- ResizeDecorator Template -->
  <ControlTemplate x:Key="ResizeDecoratorTemplate" TargetType="{x:Type Control}">
    <Grid>
      <s:ResizeThumb Height="3" Cursor="SizeNS" Margin="0 -4 0 0"
                     Position="Top"  VerticalAlignment="Top" HorizontalAlignment="Stretch"/>
      <s:ResizeThumb Width="3" Cursor="SizeWE" Margin="-4 0 0 0"
                     Position="Left" VerticalAlignment="Stretch" HorizontalAlignment="Left"/>
      <s:ResizeThumb Width="3" Cursor="SizeWE" Margin="0 0 -4 0"
                     Position="Right" VerticalAlignment="Stretch" HorizontalAlignment="Right"/>
      <s:ResizeThumb Height="3" Cursor="SizeNS" Margin="0 0 0 -4"
                     Position="Bottom" VerticalAlignment="Bottom" HorizontalAlignment="Stretch"/>
      <s:ResizeThumb Width="7" Height="7" Cursor="SizeNWSE" Margin="-6 -6 0 0"
                     Position="TopLeft" VerticalAlignment="Top" HorizontalAlignment="Left"/>
      <s:ResizeThumb Width="7" Height="7" Cursor="SizeNESW" Margin="0 -6 -6 0"
                     Position="TopRight" VerticalAlignment="Top" HorizontalAlignment="Right"/>
      <s:ResizeThumb Width="7" Height="7" Cursor="SizeNESW" Margin="-6 0 0 -6"
                     Position="BottomLeft" VerticalAlignment="Bottom" HorizontalAlignment="Left"/>
      <s:ResizeThumb Width="7" Height="7" Cursor="SizeNWSE" Margin="0 0 -6 -6"
                     Position="BottomRight" VerticalAlignment="Bottom" HorizontalAlignment="Right"/>
    </Grid>
  </ControlTemplate>

  <!-- Draggable only Designer Item -->
  <ControlTemplate x:Key="DragableDesignerItem" TargetType="ContentControl">
    <Grid>
      <s:DragThumb Template="{StaticResource DragThumbTemplate}" Cursor="SizeAll"
                   DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}"/>
      <ContentPresenter Content="{TemplateBinding ContentControl.Content}"/>
    </Grid>
  </ControlTemplate>

  <!-- Resizable only Designer Item -->
  <ControlTemplate x:Key="ResizableDesignerItem" TargetType="ContentControl">
    <Grid>
      <Control Template="{StaticResource ResizeDecoratorTemplate}"
               DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}"/>
      <ContentPresenter Content="{TemplateBinding ContentControl.Content}"/>
    </Grid>
  </ControlTemplate>

  <!-- Dragable and Resizable Designer Item -->
  <ControlTemplate x:Key="DragableAndResizableDesignerItem" TargetType="Control">
    <Grid DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}">
      <s:DragThumb Template="{StaticResource DragThumbTemplate}" Cursor="SizeAll"/>
      <Control Template="{StaticResource ResizeDecoratorTemplate}"/>
      <ContentPresenter Content="{TemplateBinding ContentControl.Content}"/>
    </Grid>
  </ControlTemplate>

</ResourceDictionary>