MahApps/MahApps.Metro — pull request #1158 by QuantumDeveloper (2014-03-14 21:50:24+00:00)
Title: [WIP] Introduce DropDownButton

![image](https://f.cloud.github.com/assets/6085009/2426216/f931605e-abc1-11e3-971b-e0c64f08f1d7.png)
Here is DropDown button. Similar to SplitButton visually, but have no:
+ Selectionchanged event
+ selectedindex/selectedItem
+ Content of Button does not change automatically

What present:
+ Handled only Click event
+ Have IconSource in button content like in SplitButton
+ Support vertical/Horizontal orientations

VerySimilar to Ribbon 2010-2013 MenuItemButton