Intellisense in IntelliJ no longer working

I'm currently running IntelliJ IDEA 13.1. While running IntelliJ 13 intellisense/autocomplete stopped working. I tried upgrading and it still doesn't work.

I can explicitly invoke code completion using ctrl+space. I looked in Settings->Editor->Code Completion and nothing looks out of place. Is there somewhere else that turns this feature on/off?

Solution 1:

For me it was because I did not have a folder marked as Source Root (it appears in blue).

To fix, right click your root source directory -> Mark As -> Source Root.

Solution 2:

Check to see if you accidentally turned on Power Save (File/Power Save Mode) I myself just discovered that File/Power Save Mode does turn it off. I was having the same problem and must have accidentally set Power Save Mode to on.

Solution 3:

File -> Settings-> Editor-> General -> Code Completion-> Auto pop up code Completion

Solution 4:

If other options mentioned is already true for you,try Setting up Sources/Test folder as Sources Root/Test Sources root as it did the trick for me. I had forgot it.

Right click on folder, choose "Mark Directory as" Test Sources or Sources Root, or whatever applicable. :)

Solution 5:

Had the same problem and none of these helped. What I realized was that on mac, control + space is used by the OS to change language inputs and it overrides intellij. So if you are on mac having multiple input languages on your keyboard, consider changing the shortcut for it :)