added ListElement

src/lib/ui/reactive/ListElement.hx

@@ -0,0 +1,42 @@
+package lib.ui.reactive;
+
+import util.ObservableArray;
+import util.Vec.Vec2;
+
+class ListElement extends UIElement {
+
+	private final content:ObservableArray<UIElement>;
+
+	public function new(content: ObservableArray<UIElement>) {
+		super();
+
+		this.content = content;
+		this.content.subscribe(value -> {
+			this.changedTrigger.trigger(null);
+			// TODO: subscribe to elements and forward onChange event
+		});
+	}
+
+	public function render(bounds:Vec2<Int>):Canvas {
+		var canvas: Canvas = new Canvas();
+		var writePoint:Vec2<Int> = {x: 0, y: 0};
+
+		for(element in this.content.get()){
+			if (bounds.y - writePoint.y <= 0) {
+				// No more space to render children
+				break;
+			}
+
+			var childRender = element.render({
+				x: bounds.x,
+				y: bounds.y - writePoint.y
+			});
+
+			canvas.combine(childRender, writePoint);
+
+			writePoint = {x: 0, y: writePoint.y + childRender.hight()};
+		}
+
+		return canvas;
+	}
+}