box
Viewer.js
A viewer for documents converted with the Box View API.
Contents
- Quick Start
- Logos
- Documentation
- Browser Support
- Contributing
- Getting Started with the Code
- Common Issues
- Change Log
- Copyright and License
Quick Start
Get the Source
You can find the pre-built development and production source files in the dist/ directory in this repository.
Viewer.js is available on npm and Bower:
npm install viewer
bower install viewer
All stable versions of viewer.js are hosted on CloudFlare's CDN, cdnjs. The unminified versions are available through the following URLs:
//cdnjs.cloudflare.com/ajax/libs/viewer.js/<VERSION>/crocodoc.viewer.css
//cdnjs.cloudflare.com/ajax/libs/viewer.js/<VERSION>/crocodoc.viewer.js
and the minified versions through:
//cdnjs.cloudflare.com/ajax/libs/viewer.js/<VERSION>/crocodoc.viewer.min.css
//cdnjs.cloudflare.com/ajax/libs/viewer.js/<VERSION>/crocodoc.viewer.min.js
For additional information, please see the cdnjs website.
v0.10.8
Development
- crocodoc.viewer.js 230.1 kB
- crocodoc.viewer.css 14.8 kB
Production
- crocodoc.viewer.min.js 51.9 kB (10.7 kB gzipped)
- crocodoc.viewer.min.css 11.4 kB (2.5 kB gzipped)
Loading a Simple Viewer
Crocodoc.createViewer(element, config)
Example
<link rel="stylesheet" href="crocodoc.viewer.min.css" />
<script type="text/javascript" src="jquery.min.js"></script>
<script type="text/javascript" src="crocodoc.viewer.min.js"></script>
<div class="viewer" style="height: 400px"></div>
<script type="text/javascript">
var viewer = Crocodoc.createViewer('.viewer', {
url: 'https://view-api.box.com/1/sessions/3c6abc0dcf35422e8353cf9c27578d5c/assets/'
});
viewer.load();
</script>
Logos
As per section 2.6 of our agreement of our API terms, we require that all apps using Box View with the Standard tier conspicuously display a Box logo when displaying Box View documents. We have included an approved logo within this repository. If your Box View plan permits custom branding of the viewer, please refer to Logo Options for instructions on how to build the viewer without the Box logo or with a custom logo.
Documentation
Library Methods
Crocodoc.createViewer(element, config)
Create and return a viewer instance initialized with the given parameters.
elementthe DOM element to initialize the viewer intostring: a query selectorElement: a DOM ElementObject: a jQuery object
configthe configuration object
Crocodoc.addPlugin(pluginName, creatorFn)
Register a new plugin with the framework. See Plugins for more details.
pluginNamethe name of the plugincreatorFna function that creates and returns an instance of the plugin (which should be an object) when called
Viewer Config
The only required config parameter is url. All others are optional.
url (required)
The url parameter specifies the base URL where the document assets are located. Viewer.js will look for document assets (including info.json, stylesheet.css, etc) in this path.
layout
The layout parameter specifies the layout mode to use. Default Crocodoc.LAYOUT_VERTICAL. See Setting the Layout Mode for available layouts.
zoom
The zoom parameter specifies the initial zoom level to use. Default Crocodoc.ZOOM_AUTO.
Possible values:
Crocodoc.ZOOM_FIT_WIDTH- zooms to fit the width of the (largest) page within the viewportCrocodoc.ZOOM_FIT_HEIGHT- zooms to fit the height of the (largest) page within the viewportCrocodoc.ZOOM_AUTO- zooms to best fit the document within the viewport
page
The page parameter specifies the initial page number to show when the document loads. Default: 1.
enableTextSelection
The enableTextSelection parameter specifies whether or not users can select text. If true, users can select text. Default: true. Note: text selection is not supported in IE 8 see Browser Support for more information.
enableLinks
The enableLinks parameter specifies whether or not hyperlinks are enabled. If true, hyperlinks are enabled. Default: true.
enableDragging
The enableDragging parameter specifies whether or not dragging is enabled. If true, click-and-drag scrolling/panning will be enabled for this document. Default: false. NOTE: text selection is not fully supported when dragging is enabled. It is recommended that you disable text selection if you plan to enable dragging.
plugins
The plugins parameter allows you to specify a map of plugin names to their respective configs. Plugin names specified in this object will be loaded when the viewer is initialized. See Plugins for more details.
Example:
{
plugins: {
// my-plugin will be initialized with the following config
'my-plugin': {
foo: 1,
bar: 2
}
}
}
queryParams
The queryParams parameter allows you to specify query string parameters to append to each asset request (eg., info.json or page-1.svg). Can be an object or string. Default: null.
Examples:
// as a string
{
queryParams: 'hello=world&foo=bar'
}
// as an object
{
queryParams: {
hello: 'world',
foo: ['bar', 'baz']
}
}
useWindowAsViewport
The useWindowAsViewport parameter allows you to specify whether to use the browser window as the viewport for the document. This is useful when the document should take up the entire browser window (e.g., on mobile devices). Use this option on mobile devices to allow the browser to auto-hide browser chrome when scrolling. Default: false.
dataProviders
The dataProviders parameter allows you override default data providers by specifying names of replacement data providers. See data providers for more info.
Example:
{
dataProviders: {
// page-svg data provider will be overridden by the 'my-page-svg' data provider
'page-svg': 'my-page-svg'
}
}
Viewer Methods
destroy()
The destroy method removes and cleans up the viewer instance.
on(name, handler)
The on method binds an event handler for the specified event name fired by the viewer object. See Event Handling for available events.
off(name[, handler])
The off method unbinds an event handler for the specified event name and handler fired by the viewer object. If handler is not given, unbinds all event handlers on this viewer object with the given name.
scrollTo(page)
The scrollTo method scrolls the viewer to the specified page. The page argument may be one of the following:
(number)- scroll the the specified page numberCrocodoc.SCROLL_PREVIOUS- scroll to the previous pageCrocodoc.SCROLL_NEXT- scroll to the next page
Examples
// scroll to page 2
viewer.scrollTo(2);
// scroll to the next page
viewer.scrollTo(Crocodoc.SCROLL_NEXT);
zoom(val)
The zoom method sets the current zoom level of the document. Possible values:
Crocodoc.ZOOM_FIT_WIDTH- zooms to fit the width of the (largest) page within the viewportCrocodoc.ZOOM_FIT_HEIGHT- zooms to fit the height of the (largest) page within the viewportCrocodoc.ZOOM_AUTO- zooms to best fit the document within the viewportCrocodoc.ZOOM_IN- zooms inCrocodoc.ZOOM_OUT- zooms out
Examples
// zoom in
viewer.zoom(Crocodoc.ZOOM_IN);
// zoom to fit width
viewer.zoom(Crocodoc.ZOOM_FIT_WIDTH);
setLayout(mode)
The setLayout method sets the layout mode. See Setting the Layout Mode for available layouts.
Examples
viewer.setLayout(Crocodoc.LAYOUT_PRESENTATION);
Event Handling
The viewer object fires several different events. You can add and remove event listeners using the on and off methods.
Example
// ready event fires when the document metadata has loaded
// and the viewer is ready to be interacted with
viewer.on('ready', function (event) {
console.log('the viewer is ready, and the document has ' + event.data.numPages + ' pages');
});
Viewer Events
asseterrorTriggered if any asset fails to load. Event properties:error- the error messageresource- the url of the resource that failed to loadstatus- the http status code
destroyTriggered when the document viewer is purposely destroyed with the destroy method.failTriggered if the document fails to load. Event properties:error- the error details
readyTriggered as soon as a document becomes viewable. Event properties:page- the current pagenumPages- total number of pages in the document
resizeTriggered when the viewer is resized. Event properties:width- the viewport widthheight- the viewport height
scrollstartTriggered when the user starts scrolling. Event properties:scrollTop- the scrollTop position of the viewportscrollLeft- the scrollLeft position of the viewport
scrollendTriggered when the user stops scrolling (or when the content stops moving if there is a momentum effect). Event properties:scrollTop- the scrollTop position of the viewportscrollLeft- the scrollLeft position of the viewport
zoomTriggered when the zoom value changes. Event properties:zoom- current zoom valuezoomMode- current zoom mode (string or null)canZoomOut- whether the viewer is able to zoom out (boolean)canZoomIn- whether the viewer is able to zoom in (boolean)
Page Events
pagefocusTriggered whenever a new page is scrolled into view. Event properties:page- page numbernumPages- total number of pages in the documentvisiblePages- an array of page numbers that are currently (fully or partially) visible in the viewport
pageloadTriggered whenever a page is loaded. Event properties:page- page number
pageunloadTriggered whenever a page is unloaded to improve performance. Event properties:page- page number
pagefailTriggered if a page fails to load. Event properties:error- the error detailspage- page number of the failed page
Setting the Layout Mode
Built-in Layout Modes
You can set a layout initially via the configuration object:
var viewer = Crocodoc.createViewer('.viewer', {
url: 'https://view-api.box.com/1/sessions/<session_id>/assets/',
layout: Crocodoc.LAYOUT_HORIZONTAL
});
Or via the setLayout method:
viewer.setLayout(Crocodoc.LAYOUT_PRESENTATION);
The currently supported layouts are:
Crocodoc.LAYOUT_VERTICALPages are scrolled vertically and arranged into one or more columns depending upon the current zoom.Crocodoc.LAYOUT_VERTICAL_SINGLE_COLUMNPages are scrolled vertically and arranged into a single column even when zoomed out.Crocodoc.LAYOUT_HORIZONTALPages within the viewer are horizontally and arranged into a single row.Crocodoc.LAYOUT_PRESENTATIONOne page is shown at a time with no scrolling. Custom transitions may be used to switch between pages.Crocodoc.LAYOUT_PRESENTATION_TWO_PAGETwo pages are shown at a time, side by side, with no scrolling. Custom transitions may be used to switch between pages.
Other Layout Modes
The above list are the modes that are included as part of the bundled viewer.js library. Here are some other layout modes that can be included alongside the library to add new layout functionality:
'vertical-two-page'Behaves likeCrocodoc.LAYOUT_PRESENTATION_TWO_PAGEfor zooming andCrocodoc.LAYOUT_VERTICALfor scrolling (gist).'presentation-vertical'Behaves likeCrocodoc.LAYOUT_PRESENTATIONfor page layout (e.g., one page visible at a time) andCrocodoc.LAYOUT_VERTICALfor zooming (gist).- [Your layout here!] - if you have a layout you'd like to contribute, create a gist like the examples above, and we'd be happy to include it.
Styling Pages
.crocodoc-page and .crocodoc-page-content classes can be used to style pages, but there are some important restrictions:
.crocodoc-page: padding should be used to adjust page spacing (don't use margin for this).crocodoc-page: background should be transparent - use.crocodoc-page-contentfor changing the background of pages (including adding a background-image, such as a loading indicator)
Examples:
.crocodoc-page {
/* 40px spacing around all sides of every page */
padding: 40px;
}
.crocodoc-page {
/* 40px spacing around the left and right sides of every page */
padding: 0 40px;
}
/* the following can be used in a layout with pages that are side-by-side to remove spacing in the middle (e.g., custom layout 'vertical-two-page') */
.crocodoc-page {
padding: 20px;
}
.crocodoc-page:nth-child(even) {
padding-left: 0;
}
.crocodoc-page:nth-child(odd) {
padding-right: 0;
}
/* add a box-shadow to pages */
.crocodoc-page-content {
box-shadow: 1px 1px 2px #000;
}
/* change the background color of pages */
.crocodoc-page-content {
background-color: papayawhip;
}
/* add a spinner image to loading pages */
.crocodoc-page-loading .crocodoc-page-content {
background: #FFF url('../images/spinner.gif') center center no-repeat;
}
/* mirror all pages horizontally (?!) */
.crocodoc-page-content {
-webkit-transform: scale(-1, 1);
-ms-transform: scale(-1, 1);
transform: scale(-1, 1);
}
Presentation Transitions
With viewer.js in presentation (Crocodoc.LAYOUT_PRESENTATION) layout mode, it is possible to add custom page transitions using pure CSS. The viewer automatically applies CSS classes to the pages appropriately so that you can write CSS that will affect the current, previous, and next pages, as well as all pages before and after the current page.
To see some examples, look at the CSS files in "presentations" example included with this repo.
The classes available are:
.crocodoc-current-page: the current page.crocodoc-preceding-page: the last "current" page (i.e. the page that had thecrocodoc-current-pageclass before the most recentpagefocusevent).crocodoc-page-prev: the previous page.crocodoc-page-next: the next page.crocodoc-page-before: any page before the current page (including the previous page).crocodoc-page-after: any page after the current page (including the next page)
Realtime Page Streaming
The Box View API conversion pipeline is optimized to minimize time to view the first page of a document. This means that a session can be created and a document can be viewed as soon as page 1 (and some metadata) is finished converting. It is now possible to use viewer.js to view documents as soon as the first page is ready by using the realtime plugin. This plugin makes a connection to the Box View API's realtime channel (a link to which is provided in the urls parameter of the session creation response), which streams updates about the conversion progress of a document.
Plugins
Plugins are reusable components that can hook into viewer.js instances to add functionality. Plugins are initialized when a viewer instance is created and have their own configuration options.
See /plugins for some plugin examples.
Example:
// add a plugin that tracks how long a user was on each page
Crocodoc.addPlugin('analytics', function (scope) {
var currentPage,
startTime,
config;
function track(page) {
var elapsed,
now = Date.now();
if (currentPage) {
elapsed = now - startTime;
if (typeof config.ontrack === 'function') {
config.ontrack(currentPage, elapsed / 1000);
}
}
startTime = now;
currentPage = page;
}
return {
// the messages property tells the viewer which messages this
// plugin is interested in
messages: ['pagefocus'],
// this onmessage method is called when a message listed above
// is broadcast within the viewer instance
onmessage: function (name, data) {
// in this case, we are only listening for one message type,
// so we don't need to do any checking against the name value
track(data.page);
},
// init is called when the viewer is initialized, and the plugin
// config is passed as a parameter
init: function (pluginConfig) {
config = pluginConfig;
}
};
});
// When creating the viewer, just include analytics in the plugins config
var viewer = Crocodoc.createViewer('.viewer', {
url: '/path/to/assets',
plugins: {
// config for the analytics plugin
analytics: {
ontrack: function (page, seconds) {
console.log(seconds + 's spent on page ' + page);
}
}
}
});
Data Providers
See the JS architecture overview for information about data providers.
Text Documents
As of v0.10.0, viewer.js supports rendering text-based documents converted by the Box View API. This functionality is in beta until further notice, and many of the page-related API methods, events, and configuration properties in viewer.js will not have any affect on text documents. The viewer will automatically switch into text-based document mode when you provide it with a URL that points to a text document converted with the View API.
Syntax Highlighting
Many source code formats will be converted to HTML for use with viewer.js such that you can enable syntax highlighting. To enable syntax highlighting, simply include a Pygments-compatible CSS stylesheet in the page with your viewer. The Box View iframe viewer uses a stylesheet similar to this one.
Browser Support
Viewer.js is supported in all modern desktop and mobile browsers. It will fall back to raster images in older browsers that do not support SVG.
NOTE: raster fall-back requires that .png representations have already been generated for the converted document.
Contributing
See CONTRIBUTING.md.
Getting Started with the Code
Dev Dependencies
To install the development dependencies, you'll need node and npm. Most node installs come with npm pre-packaged.
Once you have npm, you'll need to install grunt-cli:
npm install -g grunt-cli
Then go to the viewer.js directory and run:
npm install
That's it! You should be setup with development dependencies and ready to go.
Git Hooks
Viewer.js comes with a pre-commit git hook that runs the unit tests before allowing a commit. This is a useful way to make sure you don't accidentally commit code that breaks unit tests. To install the git hook, just run:
./install-githooks.sh
Grunt
grunt test- runsjshintandqunittests against the codegrunt doc- runstestandjsdocto generate documentation indoc/grunt(alias forgrunt default) - runstestandconcatto build the following files:dist/crocodoc.viewer.jsdist/crocodoc.viewer.css
grunt build- runsdefaultas well ascssminanduglifyto build the following compressed files (in addition to the files built ingrunt default):dist/crocodoc.viewer.min.jsdist/crocodoc.viewer.min.css
grunt serve- runs a static webserver for viewing examples and qunit tests- defaults to port 9000
- examples:
http://localhost:9000/examples - tests:
http://localhost:9000/test
Logo Options
There is an additional option that can be specified when running grunt tasks: --no-logo. If this flag is added, logos will not be embedded into the resulting CSS file (dist/crocodoc.viewer(.min).css).
If you would like to replace the Box logo with your own, you can simply replace src/images/logo.png and src/images/logo@2x.png with your own logos. Running grunt or grunt build will embed the images into the resulting CSS files.
NOTE: Make sure you are allowed to remove logos before building with this option. For more information, see Logos above.
For more information about the code, see the JS architecture overview
Common Issues
I did everything right! Why am I seeing a blank screen?
If you don't see any errors in the JavaScript console, your viewer's container element might have a height of
0px. Viewer.js does not force a height on its container element, so that needs to be set by the developer (whether it's a percent or explicit pixel value doesn't matter):<div class="viewer" style="height: 560px"></div>Are you loading assets from a
file://URL? Many browsers' security policies block these requests, so viewer.js is unable to load assets. To resolve this issue, you can run a local server usinggrunt serve(see Getting Started with the Code) or save your assets to some remote server for testing.If you are loading the assets from your own server, but the viewer is on a different origin (hostname), then you must include a CORS HTTP header with the served asset files. The quickest fix is to add the HTTP response header
Access-Control-Allow-Origin: *(but you will almost certainly want to be more specific than*, or else to restrict access to your asset files in some other way).IE 8 and 9 have a bug in the XHR/XDR implementation that causes requests to HTTPS domains to fail if they originate from an HTTP domain (with the error: "Access Denied"). If your domain is running on HTTP, Box View API URLs will fail on IE 8 and 9. At the moment, the View API only responds on HTTPS, so we have no workaround for this issue other than to recommend that you use SSL on your site.
Change Log
See CHANGELOG.md.
Copyright and License
Copyright 2014 Box, Inc. All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.