The Dynamic Components extension already comes with a toolbar of it’s own that has the button you desire.
You can use Aerilius’ Toolbar Editor extension to create custom toolbars, and to add this button to a custom toolbar.
All this aside, the DC extension is closed source and it is not always easy knowing what other extension’s UI::Command objects are. It is an advanced concept in Ruby that must use reflection to find such information (if it can be found. Ie, there are ways to hide such things.)
Anyway I have already posted here in the past on how to do this with code snippets.
(Please learn how to search categories using the magnifying glass menu [upper right].)
See: Close Component Option & Component Attribute windows using ruby script - #6 by DanRathbun
So, given the methods to actually do the opening or closing, you will need to use the UI::Toolbar class and UI::Command class to create the toolbar and buttons. (The button images will need to be a absolute path into the DC extension’s folder.)
Please change the module names (in the sample code) to something unique for yourself for the toplevel namespace module.