#716 – Using a Border As a Visual Indication That a Control Can Be Dragged
December 20, 2012 9 Comments
You can use the Thumb control to allow dragging a control around on a parent Canvas. To make it a little more obvious to the user that the control can be dragged, you can set up a Border around the control that only shows up when the user moves the mouse over the control.
<Window.Resources>
<Style x:Key="BorderVisibleOnMouse" TargetType="Border">
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="BorderBrush" Value="Transparent"/>
<Style.Triggers>
<Trigger Property="Border.IsMouseOver" Value="True">
<Setter Property="BorderBrush" Value="LightBlue"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<Canvas>
<Thumb Canvas.Left="100" Canvas.Top="60" DragDelta="Thumb_DragDelta">
<Thumb.Template>
<ControlTemplate>
<Border Style="{StaticResource ResourceKey=BorderVisibleOnMouse}">
<Label Content="Elvis Drafted!"/>
</Border>
</ControlTemplate>
</Thumb.Template>
</Thumb>
<Thumb Canvas.Left="30" Canvas.Top="180" DragDelta="Thumb_DragDelta">
<Thumb.Template>
<ControlTemplate>
<Border Style="{StaticResource ResourceKey=BorderVisibleOnMouse}">
<Label Content="Richard the Lion-Hearted Captured!"/>
</Border>
</ControlTemplate>
</Thumb.Template>
</Thumb>
</Canvas>
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superb blog..
Thanks alot this really helped!!!! Do you know how I could add to this to rotate the image about 20degrees left or right on button clicks?or on corners of the image? Thank you
You could add an event handler for the Click event where you change the Angle property of a RotateTransform. See https://wpf.2000things.com/2013/03/05/769-rotation-transforms/ to get you started.
Thank you Sean – I need to change this so that on a button click it will rotate a different image, not the actual button that is being clicked – is this easily done? I will begin to mess around with it now.
Yes, you can just have the Click handler tweak the Angle property of the rotate transform associated with the image.
Thank you again Sean, I am new to this RotateTransform, do you have any examples of using a button click to change other control angle properties? I am struggling to get my head around this.
(Without writing the code for you), the process is pretty simple:
– Create a RotateTransform object in your code
– Bind it to the RenderTransform property of your Image
– Add a Click handler
– In the Click handler, increment (or decrement) the Angle property of the RotateTransform object
Thank you for the help