Now that I was able to get my Mi MIX 3 setup with TWRP & a custom ROM (unofficial LineageOS 16 build), I started looking into remapping the AI button to something actually useful. I found a few posts to point me in the right direction, as well as a Magisk module that is supposed to handle this:
I tried out a bunch of the codes to see what would work, & for now just remapped the key to SEARCH, until I can find something better \ more useful.
There is a Magisk module for this, but I had issues making the selection during the install process: Magisk-Modules-Repo/XiaomiAI-remap. When I tried using the volume keys to change the intended function, it was actually changing my volume, not anything on the screen. Pressing the AI button during that process seemed to make changes to the choices, but still couldn’t get it working as intended. Instead, I just used the install.sh script for that module to make the change myself.
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key 115 VOLUME_UP
key 114 VOLUME_DOWN
key 102 HOME
key 528 FOCUS
key 766 CAMERA
key 689 CAMERA
key 689 to SEARCH on my device. If I can get the key to open a specific app, then I will likely end up changing the key to perform that function. Sending the keyevent for CAMERA doesn’t appear to do anything on my phone, but that may just be due to running the custom ROM. To test, the command to input key events is:
adb shell input keyevent << number or function >>