Under the ambiance theme, the tip of Eclipse pop-up is a black background, so you can't see the Java doc at all.
Of course can change the system theme in the appearance of other topics, the corresponding GTK-2.0/GTKRC to reset, such as Ubuntu12.04 the default theme for ambiance, then we can change the following path to:/usr/share/themes/ambiance/ gtk-2.0
Workaround:
cd/usr/share/themes/ambiance/gtk-2.0
sudo gedit GTKRC
The relevant code is as follows: (I modified)
Gtk-color-scheme = "Base_color: #C7EDCC \ n
Fg_color: #4c4c4c \ n
Tooltip_fg_color: #000000 \ n
Selected_bg_color: #fff0f5 \ n
Selected_fg_color: #FF6600 \ n
Text_color: #3C3C3C \ n
Bg_color: #f6f4f2 \ n
Tooltip_bg_color: #f2edbc \ n
Link_color: #DD4814 "
which
Base_color is the base color, I turn it into red bean paste green #c7edcc, so the whole eclipse of the main colour is red bean paste green, protect the eyes.
Tooltip_fg_color: It's the tip that pops up with a mouse in eclipse, with the Java doc in it, which is a foreground color, such as a font.
Tooltip_bg_color: Background color, the original is black, resulting in Doc can not see Clearly, may be adjusted to light color.
Selected_bg_color: After the background color is selected, the original background is too deep, the selected words can not see clearly, suggested changes.
Selected_fg_color: The selected foreground color, such as the font color.
Finally, restart Eclipse to get it done.
Ubuntu 12.04 Eclipse set Javadoc background color