WPF Mouse and Point Acrobatics

I was recently working on implementing mouse
gestures in WPF, and was a bit confused with the Point API. To clarify
this, I wanted to give a few quick examples that might help people
currently working with it:

To get a point relative to a UI element:

view source
print
?

1	private Point GetPointRelativeToElement(UIElement element, Point point)

2

{

3	return element.TranslatePoint(point, element);

4

}

To get the absolute screen position of a UI element,

view source
print
?

1	private Point GetAbsolutePositionOfElement(UIElement element)

2

{

3	return element.PointToScreen( new Point(0, 0));

4

}

To get the absolute midpoint of a UI element,

view source
print
?

1	private Point GetAbsoluteMidPointOfElement(FrameworkElement element)

2

{

3	Point midPoint = element.TranslatePoint( new Point(element.Width / 2, element.Height / 2), element);

4	Point absolute = PointToScreen(midPoint);

5	return absolute;

6

}<br>

To get the relative and absolute mouse position,

view source
print
?

1	private Point GetAbsoluteMousePosition()

2

{

3	return PointToScreen(Mouse.GetPosition( this ));

4

}

5

6	private Point GetMousePositionRelativeToElement(UIElement element)

7

{

8	return Mouse.GetPosition(element);

9

}

 

To programmatically adjust mouse position,

view source
print
?

1	using System.Runtime.InteropServices;

2

3	// … class declaration

4

5	[DllImport( "user32.dll" )]

6	static extern bool SetCursorPos( int X, int Y);

Now, you can call SetCursorPos(x,y) with absolute coordinates to set the mouse position.
I hope this helps!

 

http://ivolo.mit.edu/post/WPF-Mouse-and-Point-Acrobatics.aspx