Files
100DaysOfCode/day3/lib/ReactiveObject.js
2022-09-25 22:37:11 -05:00

38 lines
869 B
JavaScript

export class Reactive {
constructor(obj) {
this.contents = obj;
this.listeners = {};
this.makeReactive(obj);
}
makeReactive(obj) {
Object.keys(obj).forEach(prop => this.makePropReactive(obj, prop));
}
makePropReactive(obj, key) {
let value = obj[key];
// Gotta be careful with this here
const that = this;
Object.defineProperty(obj, key, {
get() {
return value;
},
set(newValue) {
value = newValue;
that.notify(key)
}
})
}
listen(prop, handler) {
if (!this.listeners[prop]) this.listeners[prop] = [];
this.listeners[prop].push(handler);
}
notify(prop) {
this.listeners[prop].forEach(listener => listener(this.contents[prop]));
}
}