Ubuntu loses text-editor focus from time to time

Question

I have just upgraded from Ubuntu 10.04 to 12.04.3 LTS. An annoying thing I discovered is that, in eclipse and matlab, I cannot type text sometimes. The detailed phenomena are as follows:

Eclipse

1. Happens after using auto-completion (activated by customized shortcut alt+/), or switching from other windows, or pressing ctrl+z, etc.
2. Can use mouse to move cursor around, but keyboard does not respond.
3. Using alt-tab to switch back and forth can solve the problem.

And similar things are happening in matlab, whenever I hit tab . But gedit and browser are working fine. Wonder if anyone has encountered the same problem. Thanks.

Answer 1

Problem solved. It's really a conflict between out-of-date keyboard input methods and java programs in Ubuntu 12.04. See https://askubuntu.com/questions/365205/text-editors-in-eclipse-matlab-loses-focus-occasionally-after-upgrading-to-12-04.