class View extends Listenable {
	/**
	 * The constructor accepts a DOM element as a parameter.
	 * If it is omitted, a new element is created using the tag name that the class defines.
	 * If no class name is defined, the constructor name in kebab case is used instead.
	 */
	constructor(element = null) {
		super();

		this.element = element;
		if (!this.element) {
			var tagName = this.getTagName();
			if (!tagName) {
				tagName = this.constructor.name.toKebabCase();
			}
			this.element = document.createElement(tagName);

			this.element.setAttribute("view-class", this.constructor.name);

			this.build(this.element);
		}
	}

	/**
	 * The build function is called in the constructor when no element was passed as the base.
	 * Override it to create custom subviews or manipulate the root element.
	 * Don't forget to return the element in the end!
	 */
	build(element) {
		return element;
	}

	/**
	 * Returns the tag name of this element.
	 * Override this if you want to have a custom tag name for your custom view class.
	 * If this function is not overridden, the class name is used for the tag name for newly created elements (converted to kebab-case).
	 * 
	 * This functionality is used for view classes that are inherited by subclasses.
	 * That is because the CSS rules of the superclass view should generally also apply to the subclass view.
	 * Therefore, the subclass view can get the tag name of the superclass by not overriding this function.
	 * Only the view-class attribute will indicate the true nature of the element in this case, which will be useful for specific CSS styling.
	 */
	getTagName() {
		return null;
	}

	/**
	 * Called once the view has been processed by UIKit during the view controller initialization.
	 */
	viewDidLoad() { }

	/**
	 * Called everytime before the view is shown.
	 * The layout is already done at this step, so it's safe to use scrollWidth and scrollHeight and what not.
	 */
	viewWillAppear() { }

	/**
	 * Called everytime after the view is shown.
	 */
	viewDidAppear() { }

	/**
	 * Called everytime before the view is hidden.
	 */
	viewWillDisappear() { }

	/**
	 * Called everytime after the view is hidden.
	 */
	viewDidDisappear() { }
}

UIKit.registerViewType(View);