#407 Feature request: collapse project tree action

[Riot]

Sometimes the project tree, when it's huge, can take a lot of scrolling, and manually collapsing it is labour intensive. A shortcut to collapse the entire project tree would be useful - it could appear in the right-click menu, project tree->collapse all.

[ollydbg]

My guess is to implement this feature, we need to add a new menu entry in the file "src\projectmanagerui.cpp", because the class ProjectManagerUI can access to the project manager's tree (wxTreeCtrl).