Customizing the Presentation Mode in Our JavaScript Viewer

let _instance = null;

const initialViewState = new PSPDFKit.ViewState({
	scrollMode: PSPDFKit.ScrollMode.PER_SPREAD,
	layoutMode: PSPDFKit.LayoutMode.SINGLE,
});

let fullscreenElement =
	typeof defaultConfiguration.container === 'string'
		? document.querySelector(defaultConfiguration.container).parentNode
		: defaultConfiguration.container.parentNode;

registerFullscreenChangeEvents();

const toolbarItems = [
	{ type: 'pager' },
	{ type: 'spacer' },
	{ type: 'sidebar-thumbnails' },
	{ type: 'search' },
	{ type: 'highlighter' },
];

// A custom toolbar item to toggle fullscreen mode.
const fullScreenToolbarItem = {
	type: 'custom',
	title: 'Toggle full screen mode',
	onPress: () => {
		// You can implement the fullscreen mode on your own. Either see our
		// functions below for information on how to activate it, or look at our guides:
		// https://pspdfkit.com/guides/web/features/fullscreen-mode/
		if (isFullscreenEnabled()) {
			exitFullscreen();
		} else {
			requestFullScreen(fullscreenElement);
		}
	},
};

if (isFullScreenSupported()) {
	toolbarItems.push(fullScreenToolbarItem);
}

return PSPDFKit.load({
	...defaultConfiguration,
	toolbarItems,
	toolbarPlacement: PSPDFKit.ToolbarPlacement.BOTTOM,
	initialViewState,
}).then((instance) => {
	_instance = instance;
});

function onFullScreenChange() {
	_instance.setViewState(
		_instance.viewState.set('showToolbar', !isFullscreenEnabled()),
	);
}

function registerFullscreenChangeEvents() {
	document.addEventListener('fullscreenchange', onFullScreenChange);
	document.addEventListener('webkitfullscreenchange', onFullScreenChange);
	document.addEventListener('mozfullscreenchange', onFullScreenChange);
	document.addEventListener('MSFullscreenChange', onFullScreenChange);
}

function isFullscreenEnabled() {
	return (
		document.fullscreenElement ||
		document.mozFullScreenElement ||
		document.webkitFullscreenElement ||
		document.msFullscreenElement
	);
}

function isFullScreenSupported() {
	return (
		document.fullscreenEnabled ||
		document.mozFullScreenEnabled ||
		document.msFullScreenEnabled ||
		document.webkitFullscreenEnabled
	);
}

function requestFullScreen(element) {
	if (element.requestFullscreen) {
		element.requestFullscreen();
	} else if (element.mozRequestFullScreen) {
		element.mozRequestFullScreen();
	} else if (element.webkitRequestFullscreen) {
		element.webkitRequestFullscreen();
	} else if (element.msRequestFullscreen) {
		element.msRequestFullscreen();
	}
}

function exitFullscreen() {
	if (document.webkitExitFullscreen) {
		document.webkitExitFullscreen();
	} else if (document.mozCancelFullScreen) {
		document.mozCancelFullScreen();
	} else if (document.msExitFullscreen) {
		document.msExitFullscreen();
	} else if (document.exitFullscreen) {
		document.exitFullscreen();
	}
}