The alternate row styling is simply commented out in the Ubuntu default themes.
Editing the theme file
Look for the /gtk-3.0/gtk-widgets.css file within your favorite theme.
- Custom themes that you installed should be located in ~/.themes (the home folder)
- The default Ubuntu themes are located in /usr/share/themes/.
Ubuntu 14.04 (Nautilus, Nemo)
Edit the gtk-widgets.css file in your theme folder. So with the Ubuntu default theme for example, that would be /usr/share/themes/Ambiance/gtk-3.0/gtk-widgets.css. Find the following css rule around line ~2224, and add your chosen background color:
view row:nth-child(even){
/*background-color: @base_color;*/
background-color: #ECF2FD; /* <-- add this */
}
Ubuntu 13.04
For example, if you are using Ambiance then the file to edit is located at /usr/share/themes/Ambiance/gtk-3.0/gtk-widgets.css.
Uncomment the rules at approx. line 2181, from:
GtkTreeView row:nth-child(odd) {
/*background-color: shade (@base_color, 0.965);*/
}
To:
GtkTreeView row:nth-child(odd) {
background-color: shade (@base_color, 0.965);
}
Or use a #RRGGBB colour, the classic OS X light blue colour for example:
GtkTreeView row:nth-child(odd) {
background-color: #ECF2FD;
}
Editing those rules will work for Nautilus 3.6, as well as Nemo. Nemo, by default, will not show alternating row styles as it will be using the Ubuntu themes.
Note that after editing the file you may have to close and reopen the file browser. If it doesn't work, try relogging. The themes appear to be cached so even if you switch themes with Ubuntu-tweak, it may not display the change immediately.
Using an alternative theme
If you prefer to avoid editing the files you can use an alternative theme. A really nice one is MediterraneanNight Series ("White" and "Night" are the closest to the light/dark themes).
Here's an example with MediterraneanNight White:
Best Answer
I don't think this is possible because of the nature of this view.
However: to select multiple files I suggest you learn the Shift keyboard shortcut for selecting files "in a row" and Ctrl for selecting individual files "all over the place" as it were. You'll quickly pick these up.