ToggleBehavior.js

export class ToggleBehavior extends Behavior {
	changeOffset(container, offset) {
		var bar = container.first;
		var button = bar.next;
		if (offset < 0)
			offset = 0;
		else if (offset > this.size)
			offset = this.size;
		else
			offset = Math.round(offset);
		this.offset = offset;
		bar.state = button.state = container.active ? 1 + (this.offset / this.size) : 0;
		button.x = bar.x + this.offset + 1;
	}
	onCreate(container, data) {
		this.data = data;
	}
	onDataChanged(container) {
		this.changeOffset(container, this.data.value ? this.size : 0);
	}
	onDisplaying(container) {
		var bar = container.first;
		var button = bar.next;
		this.size = bar.width - button.width - 2;
		let data = this.data;
		this.onDataChanged(container);
	}
	onTimeChanged(container) {
		this.changeOffset(container, this.anchor + Math.round(this.delta * container.fraction));
	}
	onTouchBegan(container, id, x, y, ticks) {
		if (container.running) {
			container.stop();
			container.time = container.duration;
		}
		this.anchor = x;
		this.moved = false;
		this.delta = this.offset;
		container.captureTouch(id, x, y, ticks);
	}
	onTouchEnded(container, id, x, y, ticks) {
		var offset = this.offset;
		var size =  this.size;
		var delta = size >> 1;
		if (this.moved) {
			if (offset < delta)
				delta = 0 - offset;
			else 
				delta = size - offset;
		}
		else {
			if (offset == 0)
				delta = size;
			else if (offset == size)
				delta = 0 - size;
			else if (x > (container.x + (container.width >> 1)))
				delta = size - offset;
			else
				delta = 0 - offset;
		}
		if (delta) {
			this.anchor = offset;
			this.delta = delta;
			container.duration = 125 * Math.abs(delta) / size;
			container.time = 0;
			container.start();
		}
		var value = ((this.offset + delta) == 0) ? false : true;
		let data = this.data;
		if (data.value != value) {
			data.value = value;
			this.onValueChanged(container);
		}
	}
	onTouchMoved(container, id, x, y, ticks) {
		this.moved = Math.abs(x - this.anchor) >= 8;
		this.changeOffset(container, this.delta + x - this.anchor);
	}
	onValueChanged(container) {
	}
};