mime-chat/src/modules/keyDownHandler/useKeyDownHandler.ts
2021-02-13 14:01:37 -06:00

51 lines
1.5 KiB
TypeScript

import { ref } from "vue";
import keyboardNameMap from "./keyBoardMaps/keyboardNameMap";
import keyboardCharMap from "./keyBoardMaps/keyboardCharMap";
interface KeyDownEvent {
keyCode: number;
shiftKey: boolean;
}
// This catches keys from a physical keyboard, a soft keyboard on a tablet, or a
// scanner attached via USB
export default function useKeyDownHandler(enterCallback: (input: string) => void | null) {
const input = ref("");
function keyDownHandler(e: KeyDownEvent) {
// keyboardCharMap is an array of arrays, with each inner
// array having 2 columns - un-shifted, and shifted values.
// iCol = 0 is the un-shifted value, while iCol=1 is the shifted value.
// See the "keyboardCharMap", below, for printable characters.
// MODIFY keyboardCharMap to suit your needs if you want
// more/less/different characters to be considered "printable".
let iCol = 0;
if (e.shiftKey) {
iCol = 1;
}
const ch = keyboardCharMap[e.keyCode][iCol];
// Optionally do things with non-printables,
// like CR, ESC, Backspace, LF, Tab, Arrows, F1-F24, etc.
// See the arrary "keyboardNameMap", below, for possible keys.
const cmd = keyboardNameMap[e.keyCode];
switch (cmd) {
case "ENTER":
enterCallback(input.value);
break;
case "BACK_SPACE":
input.value = input.value.slice(0, -1);
break;
case "ESCAPE":
input.value = "";
break;
default:
input.value += ch;
}
}
return {
keyDownHandler,
input
};
}