src/vs/workbench/browser/parts/activitybar/activitybarActions.ts/SwitchSideBarViewAction/run
class SwitchSideBarViewAction:	async run(accessor: ServicesAccessor): Promise<void> {
		const activityBarService = accessor.get(IActivityBarService);
		const viewletService = accessor.get(IViewletService);

		const visibleViewletIds = activityBarService.getVisibleViewContainerIds();

		const activeViewlet = viewletService.getActiveViewlet();
		if (!activeViewlet) {
			return;
		}
		let targetViewletId: string | undefined;
		for (let i = 0; i < visibleViewletIds.length; i++) {
			if (visibleViewletIds[i] === activeViewlet.getId()) {
				targetViewletId = visibleViewletIds[(i + visibleViewletIds.length + this.offset) % visibleViewletIds.length];
				break;
			}
		}

		await viewletService.openViewlet(targetViewletId, true);
	}