Ubuntu 10.04.1 new theme has by default windows background colors set to black.
I don't want to change that.
In Eclipse, the interface didn't change much due to 10.04.1 - except one annoying thing:
when the mouse stops on a keyword - variable for instance - the type (...) of that keyword is displayed in a small pop-up window.
However, since 10.04.1, that text is in black color while the background is also black.
Is there to change that background color in Eclipse?
All the various popup background color are managed in Preferences > Java > Editor (like the one for the completion list popup in bug 133615).
Other background colors are in General > Appearance > Colors and Font (type background in the filter field).
But the type popup seems to stick to a system color, which is why you see a black background.
If this is truly the case, it is worth reporting as a bug.
The OP confirms it is not the case, actually:
It was in
Preferences > C/C++ > Editor > Source hover background, and had to untick the "System default" (because the shown color was light-gray!)