@ -118,6 +118,42 @@ We've added shortcuts to make common modifier/tap (mod-tap) mappings more compac
* `LCAG_T(kc)` - is CtrlAltGui when held and *kc* when tapped
* `MEH_T(kc)` - is like Hyper, but not as cool -- does not include the Cmd/Win key, so just sends Alt+Ctrl+Shift.
### The Leader key: A new kind of modifier
If you've ever used Vim, you know what a Leader key is. If not, you're about to discover a wonderful concept. :) Instead of hitting Alt+Shift+W for example (holding down three keys at the same time), what if you could hit a _sequence_ of keys instead? So you'd hit our special modifier (the Leader key), followed by W and then C (just a rapid succession of keys), and something would happen.
That's what `KC_LEAD` does. Here's an example:
1. Pick a key on your keyboard you want to use as the Leader key. Assign it the keycode `KC_LEAD`. This key would be dedicated just for this -- it's a single action key, can't be used for anything else.
2. Include the line `#define LEADER_TIMEOUT 300` somewhere in your keymap.c file, probably near the top. The 300 there is 300ms -- that's how long you have for the sequence of keys following the leader. You can tweak this value for comfort, of course.
3. Within your `matrix_scan_user` function, do something like this:
```
void matrix_scan_user(void) {
LEADER_DICTIONARY() {
leading = false;
leader_end();
SEQ_ONE_KEY(KC_F) {
register_code(KC_S);
unregister_code(KC_S);
}
SEQ_TWO_KEYS(KC_A, KC_S) {
register_code(KC_H);
unregister_code(KC_H);
}
SEQ_THREE_KEYS(KC_A, KC_S, KC_D) {
register_code(KC_LGUI);
register_code(KC_S);
unregister_code(KC_S);
unregister_code(KC_LGUI);
}
}
}
```
As you can see, you have three function. you can use - `SEQ_ONE_KEY` for single-key sequences (Leader followed by just one key), and `SEQ_TWO_KEYS` and `SEQ_THREE_.EYS` for longer sequences. Each of these accepts one or more keycodes as arguments. This is an important point: You can use keycodes from **any layer on your keyboard**. That layer would need to be active for the leader macro to fire, obviously.
### Temporarily setting the default layer
`DF(layer)` - sets default layer to *layer*. The default layer is the one at the "bottom" of the layer stack - the ultimate fallback layer. This currently does not persist over power loss. When you plug the keyboard back in, layer 0 will always be the default. It is theoretically possible to work around that, but that's not what `DF` does.
Erez Zukerman
9 years ago