Improved Global Keyboard Shortcut listeners

[sancarn]

Improved listeners using IOHook so can listen to meta key and others.

• Create and implement global key listeners in node-global-key-listener. Progress see here
• Implement a wrapper in LM around node-global-key-listener.
• Create a settings type for global listeners
  • Make the settings store the keycodes, and display character names obtained from the browser
  • Add a function to this setting type to register a listener for it

[sancarn]

Currently we have an issue installing global hotkeys in LaunchMenu.

Option 1: Do nothing

Currently we used Electron's global hotkey libraries but these are very limited as they use more restricted hotkey binding systems.

Option 2: Use IOHook

Problems: IOHook only supports a set of node and electron versions. Building is a bit of a nightmare.

Option 3: Use native implementation

Windows implementation

This implementation is described here. I've included some pseudocode below.

const WH_GETMESSAGE = 3
function Register(){
   this.hook = SetWindowHookEx(WH_GETMESSAGE, pointerTo(MyMsgProc), 0, 0)
}
function Unregister(){
  if(!UnhookWindowsHookEx(this.hook)){
    throw "Cannot unhook"
  }
}
function MyMsgProc(code, wParam, lParam){
  if(code == WM_KEYDOWN){
    //Detect keycode in wParam
    
    //Propogation
    if(!stopPropogation){
      CallNextHookEx(this.hook, code, wParam, lParam)
    }
  } else {
    CallNextHookEx(this.hook, code, wParam, lParam)
  }
}

Mac implementation

The following is the implementation for Macs written in swift.

see implementation of an event-tap in mac os here

Option 4: Use Node FFI

The above could be implemented in Node-FFI. This could mean that we have a bit of a build nightmare though...

Windows Implementation