feat(behaviors): Leader key

[nickconway]

Adds leader key functionality

[grezp]

Any update on this branch merging to main?

[vladsolokha]

I don't understand the difference of this "leader key" and a sticky layer. Can someone differentiate?

[cougarten]

I don't understand the difference of this "leader key" and a sticky layer. Can someone differentiate?

you can do more than 2 key presses and it can chain arbitrary long sequences as the triggers.

e.g. "super > s > e" for "leader key" > "shortcuts" > "email" to trigger spelling your email address (or anything you want).

[ujl123]

I don't understand the difference of this "leader key" and a sticky layer. Can someone differentiate?

Other uses I use leader keys in QMK is (all are for windows)

Leader Key + B O O T = qmk reset Leader Key + R G B = toggle rgb Leader Key + Q = Alt F4 Leader key + Z Z Z = system shutdown Leader key + T O P = CTRL + SHIFT + ESC (task manager in windows) Leader Key + MKDIR = CTRL + SHIFT + N (new folder) Leader Key + RM = shift delete (hard delete in windows) Leader KEy + PIN = windows pin (not recommended storing passwords on your keyboard but I'm lazy).

I'm hoping that this gets reviewed and can be merged into the main branch though as this is a major component that makes my 32 key keyboard work in QMK (along with tap mods, tap dances autoshifts, custom autoshift keys)

[arabshapt]

Please try to finish this feature... I will soon try to merge it on my branch, but it would be great to have it on master. I do not understand how people are not showing more interest for it. If it is easy to add key sequences(similar to vimrc) then it would be even better, but I think that can be done with a custom function... The main thing is having it on master and bugfree:) Thank you all but especially @nickconway and @petejohanson for working on it🙂

[arabshapt]

Is there any limitation regarding number of sequences that can be created? For combos there are (I think) 5 combos that can use the same key position. Could one create e.g. 900 sequences: leader + letter_1 + letter_2 = shortcut/macro? So three key taps, around 900 unique sequences. Would it be possible with this implementation?

[tvdab]

I was a happy user of the leader key feature in my previous zmk build. Recently I tried updating my firmware to the latest release of zmk (c9c620d19f603ea0c9d4264eff885912803ff74d) and also update from zephyr sdk 0.15 to 0.16. Everything seems to work, except for the leader key. The leader key acts like a transparent key. Also running the test tests/leader/basic fails:

❯ west test tests/leader/basic
Running tests/leader/basic:
--- tests/leader/basic/keycode_events.snapshot	2024-02-25 22:11:10.516535082 +0100
+++ build/tests/leader/basic/keycode_events.log	2024-02-25 22:35:07.778445825 +0100
@@ -1,4 +1,2 @@
-leader: leader key activated
-pressed: usage_page 0x07 keycode 0x04 implicit_mods 0x00 explicit_mods 0x00
-released: usage_page 0x07 keycode 0x04 implicit_mods 0x00 explicit_mods 0x00
-leader: leader key deactivated
+pressed: usage_page 0x07 keycode 0x1E implicit_mods 0x00 explicit_mods 0x00
+released: usage_page 0x07 keycode 0x1E implicit_mods 0x00 explicit_mods 0x00
FAILED: tests/leader/basic

Could someone verify if the leader key works with zephyr sdk 0.16 and a recent version of zmk? Maybe I'm doing something wrong...

[caksoylar]

I am guessing this needs to be rebased for #2028.

[tvdab]

I found why it wasn't working in Zephyr 3.5. This is what needs to be changed in order to make it work again:

--- a/app/src/behaviors/behavior_leader_key.c
+++ b/app/src/behaviors/behavior_leader_key.c
@@ -47,8 +47,8 @@ static const struct behavior_driver_api behavior_leader_key_driver_api = {
 #define LEAD_INST(n)                                                                               \
     static struct behavior_leader_key_config behavior_leader_key_config_##n = {                    \
         .timerless = DT_INST_PROP(n, timerless), .timeout_ms = DT_INST_PROP(n, timeout_ms)};       \
-    DEVICE_DT_INST_DEFINE(n, behavior_leader_key_init, NULL, NULL,                                 \
-                          &behavior_leader_key_config_##n, APPLICATION,                            \
+    BEHAVIOR_DT_INST_DEFINE(n, behavior_leader_key_init, NULL, NULL,                                 \
+                          &behavior_leader_key_config_##n, POST_KERNEL,                            \
                           CONFIG_KERNEL_INIT_PRIORITY_DEFAULT, &behavior_leader_key_driver_api);

 DT_INST_FOREACH_STATUS_OKAY(LEAD_INST) 

There are probably more changes to be made (#2028) to update everything to zephyr 3.5.