Can I use bookmarks/custom activity in Workflow designer?

This is sort of a noob question...

I've seen how to create an activi开发者_运维百科ty that works with bookmarks here, but how can I use this custom code as an Activity inside a workflow designer?

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In Visual Studio any activity in the same solution will automatically be added to the toolbox when you open the workflow designer. If you are using self hosting or a previously created library of activities in VS2010 you need to add it to the toolbox yourselfs.