mapcomplete/UI/UIElement.ts
2020-06-27 03:06:51 +02:00

80 lines
No EOL
2 KiB
TypeScript

import {UIEventSource} from "./UIEventSource";
export abstract class UIElement {
private static nextId: number = 0;
public readonly id: string;
public readonly _source: UIEventSource<any>;
private _hideIfEmpty = false;
protected constructor(source: UIEventSource<any>) {
this.id = "ui-element-" + UIElement.nextId;
this._source = source;
UIElement.nextId++;
this.ListenTo(source);
}
protected ListenTo(source: UIEventSource<any>) {
if(source === undefined){
return;
}
const self = this;
source.addCallback(() => {
self.Update();
})
}
Update(): void {
let element = document.getElementById(this.id);
if (element === null || element === undefined) {
// The element is not painted
return;
}
element.innerHTML = this.InnerRender();
if(this._hideIfEmpty){
if(element.innerHTML === ""){
element.parentElement.style.display = "none";
}else{
element.parentElement.style.display = undefined;
}
}
this.InnerUpdate(element);
}
HideOnEmpty(hide : boolean){
this._hideIfEmpty = hide;
this.Update();
return this;
}
// Called after the HTML has been replaced. Can be used for css tricks
InnerUpdate(htmlElement : HTMLElement){}
Render(): string {
return "<span class='uielement' id='" + this.id + "'>" + this.InnerRender() + "</span>"
}
AttachTo(divId: string) {
let element = document.getElementById(divId);
if(element === null){
console.log("SEVERE: could not attach UIElement to ", divId);
return;
}
element.innerHTML = this.Render();
this.Update();
return this;
}
protected abstract InnerRender(): string;
public Activate(): void {};
public IsEmpty(): boolean {
return this.InnerRender() === "";
}
}