Semantic Shortcut Key Combination

CUE has a semantic shortcut feature (described in Semantic Shortcuts) that provides keyboard-only access to CUE features. By default, a semantic shortcut is introduced by pressing the Shift key twice in quick succession: this displays a small dialog listing additional keys the user can press to complete a shortcut and execute an action. You can, however, replace the Shift Shift introductory key sequence with some other key sequence or key combination if required. You can also change the maximum interval between the keypresses in an introductory key sequence.

To change the default semantic shortcut settings:

  1. If necessary, switch user to root.

    $ sudo su
  2. Open /etc/escenic/cue-web/config.yml for editing. For example:

    # nano /etc/escenic/cue-web/config.yml
  3. To replace the default Shift Shift sequence add the following setting:

    keyboardShortcuts:
      semanticToggle: "new-sequence"

    where new-sequence is a key sequence specification such as mod mod (which specifies a key sequence) or mod+alt+a (which specifies a key combination).

  4. If you are using a key sequence (either the default shift shift or a sequence you have defined yourself), you can also control how quickly the user has to type the sequence in order for it to be recognized. By default, the interval between the two keypresses must not exceed 500 milliseconds. To increase the interval to 600 milliseconds, for example, you would need to enter a resetSequenceTimeout property as a child of the same keyboardShortcuts property:

    keyboardShortcuts:
      resetSequenceTimeout: 600
  5. Save the file.

  6. Enter:

    # dpkg-reconfigure cue-web-3.12

    This reconfigures CUE with the change you made.

Note that:

  • The key identifier mod represents the ctrl key on Windows or the command key on Mac. You should always use mod rather than ctrl or command to ensure that semantic shortcuts will work on both platforms.

  • You can in theory use any sequence or combination of keys to introduce semantic shortcuts, but in order to avoid problems you are recommended to stick to either a modifier sequence such as shift shift or a combination of modifiers and characters such as mod+alt+a. You should also take care to avoid combinations that are already in use either by CUE itself or by the browser.

For more detailed information about supported key combinations and how to specify them, see the documentation of the Javascript library used to provide this functionality: Mousetrap.