Asking Emacs to highlight more clearly which window (pane) has the focus (cursor)

Question

Say I have my Emacs window split into multiple tiles, e.g.:

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When I switch between tiles (aka windows in Emacs) to edit my files (e.g. using C-x o), I can see on which tile I am by visually locating the cursor (point) on the screen and checking the difference in shading in the status bar of each tile:

However, locating the cursor on a large screen is not easy AND the difference in shading on the status bar where the cursor is is almost negligible:

This is what a status bar looks like when the corresponding window is selected:

             

This is what it looks like when the corresponding window is not selected (notice the green is a bit dimmer)

             

The above is with the color theme zenburn on GNU Emacs 23.3.1.

My question is: Is there a way to have Emacs more clearly indicate which window/tile/buffer is the one that has the focus?

Answer 1

Absolutely!

You can change the modeline to highlight the active bar using the following in your .emacs (change colors and style to suit your preferences of course).

(set-face-attribute  'mode-line
                 nil 
                 :foreground "gray80"
                 :background "gray25" 
                 :box '(:line-width 1 :style released-button))
(set-face-attribute  'mode-line-inactive
                 nil 
                 :foreground "gray30"
                 :background MY_BG_COLOR 
                 :box '(:line-width 1 :style released-button))

Since it seems you are using the Zenburn color theme, you can also fix it within there. Just open the file within your color-theme library named zenburn.el (or it might be color-theme-zenburn.el) and search for the following lines:

`(mode-line
  ((,class (:foreground ,zenburn-green+1
                       :background ,zenburn-bg-1
                       :box (:line-width -1 :style released-button)))))
`(mode-line-buffer-id ((,class (:foreground ,zenburn-yellow :weight bold))))
`(mode-line-inactive
  ((,class (:foreground ,zenburn-green-1
                       :background ,zenburn-bg-05
                       :box (:line-width -1 :style released-button)))))

and change the values of the background and foreground colors as you see fit.

Answer 2

For a quicker solution, you can use the Smart Mode Line plugin for Emacs: a color-coded, fixed width mode line. Works great with the Zenburn theme (I'm using both right now).

It's available in the ELPA, by the way.