I saw someone doing something in eclipse today that looked quite useful.
When he switched tasks the Project Explorer view changed to only show the files related to that task.
See the (2nd) screenshot here to see more details of the difference of having focus on and off
I had a read about IDEAs Tasks and Contexts https://www.jetbrains.com/help/idea/2016.2/managing-tasks-and-context.html but it isn't really as useful.
I can sort of do it with scopes but they are a pain to configure.
e.g. there is no context menu in the Project or Version Control tool windows that says "Add files to scope". and the scopes are not bound to tasks.
To be honest I haven't found the tasks and contexts much use at all. In my workflow I add changelists in the VCS window to separate code from other files that might have changed and IDEA creates loads of Tasks and Contexts and I do nothing with them :(