Change key mapping to allow keyboard chording (Mac)

Question

I'm looking to find a way of mapping multiple simultaneous keypresses to one action. As an example something similar to hitting ctrl-option- at the same time but instead using just normal letters such as p-s-v. Pressing these keys simultaneously would perform some action.

I have downloaded both Ukelele and KeyRemap4Macbook but both only allow you to remap a single key--not including the special keys(ctrl,alt,etc).

How can I accomplish this?

Answer 1

You can use a private.xml like this with KeyRemap4MacBook:

<?xml version="1.0"?>
<root>
  <item>
    <name>test</name>
    <identifier>test</identifier>
    <autogen>__SimultaneousKeyPresses__ KeyCode::Q, KeyCode::W, KeyCode::E</autogen>
  </item>
</root>

For more than two keys, use @begin and @end:

__SimultaneousKeyPresses__
@begin
KeyCode::Q, KeyCode::W, KeyCode::E
@end
@begin
KeyCode::R
@end

This would make pressing F and I simultaneously open Finder:

<vkopenurldef>
  <name>KeyCode::VK_OPEN_URL_FINDER</name>
  <url>file:///System/Library/CoreServices/Finder.app</url>
</vkopenurldef>
<item>
  <name>test</name>
  <identifier>test</identifier>
  <autogen>__SimultaneousKeyPresses__ KeyCode::F, KeyCode::I, KeyCode::VK_OPEN_URL_FINDER</autogen>
</item>

See https://raw.github.com/tekezo/KeyRemap4MacBook/master/Tests/lib/string/data/checkbox.xml for more examples.