export class TrackedProperty { private trackedValue?:T; private updateCallback?:(value:T) => void; constructor(initialValue?:T) { this.trackedValue = initialValue; } public set OnChange(value:() => void) { this.updateCallback = value; } public get Value() { return this.trackedValue; } public set Value(value) { this.trackedValue = value; if (this.updateCallback && value) { this.updateCallback(value); } } }