linux - Custom hotkey/shortcut to open/bring to front an app

I don't imagine this is built into the system, but is it possible to do it without too much hassle?

Say I open a specific program with a hotkey, and when I press that hotkey again, the program window is brought to the front.

I want to do this on Ubuntu 9.04.

Maybe with D-Bus? Any experts?

Update: Here's what I ended up with in case it's of help to somebody:

#!/bin/bash
if [ -f "/tmp/myterm.pid" ]; then
  WID=`cat /tmp/myterm.pid`
  xdotool windowactivate $WID
  if [ "$?" != "0" ]; then
    WID=""
  fi
else
  WID=`xdotool search --title "UNIQUE TITLE" | head -1`
fi

if [ "$WID" == "" ]; then
  /usr/bin/gnome-terminal --window-with-profile=MYPROFILE "$@"
  WID=`xdotool search --title "UNIQUE TITLE" | head -1`
  echo $WID > /tmp/myterm.pid
else
  xdotool windowactivate $WID
fi

Surely it can be simplified, but I'm no bash wiz. Also, for my example to work, I created a custom profile in Terminal that applies a unique title to the window so it can be found later. The possibilities are endless!

Answer

The wmctrl program is just what you're looking for (sudo apt-get install wmctrl). You can use the wmctrl -a "AppTitle" command to bring the app to the front. wmctrl -l will list all available windows, so it should be easy to write a shell script that checks if your program is running and either launches it or brings it to the front. Then you can just bind that to a keyboard shortcut.

First save the following script somewhere, I'll use /home/jtb/code/bringToFront. It takes two arguments, the first is what you would type at the terminal to launch the program, the second is a substring of the program window's title. If there is no constant unique string in the title then you'll need to do a bit more work to find the program's window.

#!/bin/bash
if [ `wmctrl -l | grep -c "$2"` != 0 ]  
then
    wmctrl -a "$2"
else
    $1 &
fi

2. 
   

   With the script in your current directory, run chmod +x bringToFront to make the script executable. Then make sure it works; to launch/focus firefox you could run ./bringToFront firefox "Mozilla Firefox".

   
   


3. 
   

   Now we need to bind a shortcut key. Run gconf-editor and navigate the folder structure to the left to /apps/metacity/keybinding_commands.

   
   


4. 
   

   Double click on the first command with a blank value, probably command_1. Type the full path to the script and provide the two parameters, e.g. /home/jtb/code/bringToFront firefox Firefox.

   
   


5. 
   

   From the panel on the left, select global_keybindings, the next folder up. Find the run entry matching the command you just defined, probably run_command_1. Double click it and type the keyboard shortcut you want to use. Put the modifiers in angle brackets, e.g. F.

   
   

Now Control + Alt + F will bring your firefox window to the front, or launch it if it's not already running.