Simpel Drag and Drop an Ellipse into another ellipse

Question

Hi all, i am new here so please excuse me if I make any mistakes.

I have been searching every post on drag and drop, and got tons of different solution. But none of them really solves this problem. I am making a Mastermind game, and i want to be able to drag an ellipse into another ellipse.

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By the way im making it in WPF with all the shapes predefined in XAML. To clear it up, I would like to be able to drag the green ellipse into the gray one. It should not be possible to drop it anywhere else on the canvas.

I really hope someone can help, im been trying to do this for 2 days, talking about a lousy productivity :)

Best Regards John

** EDIT **

Ok it seems like i got it working, even though the drag an drop thing is a little buggy. If anybody is up for a game of MasterMind, try it out =)