IntelliJ — how to configure what to show on vertical bar

Question

I am moving from Eclipse to IntelliJ -- overall experience has been great, but I can't find a good way to customize the vertical bar (the right-most one) to the right of the opend source file. By defaul that is used to display the problems of my code.

Specifically, I want to add occurrences of a selected symbol to the vertical bar. I also want to change the colors of each annotation on the vertical bar.

Where do I configure that?

[EDIT, screenshot to show the vertical bar I am talking about]

And this is the desired behavior I have in eclipse: when I highlight a symbol, the occurrence of this symbol is on the right-most vertical bar. if I click on the block on the vertical bar, I can go to the usage of that symbol. I can also change the color of that block.

Apologies for blacking out the code --- required by company policy.

Answer 1

Highlighted usage of a particular symbol appears in the right-hand gutter, which you have highlighted. What also appears is a bit of hovertext for each occurrence, telling you what context it's in and whether or not it's being assigned.

If you click on that, then you will also be taken to its usage wherever it happens to be.

If you want to change the color of it, then that's controlled by Settings > Colors and Fonts > General > Identifier under caret (write) and Identifier under caret. Here is where you'd make the change to whichever color showed up both when you hovered over the text, and what showed up in the gutter - depending on if you were writing to that variable or not.

Answer 2

Its under Settings->Editor->Colors & Fonts->General submenu "Identifier under Caret" from there you can set background highlight color and error stripe mark. You will need to "Save as..." in order to edit this.

See picture with red dots near relevant information.