cb61bdee34
Having thought *briefly* about using `css-vars-ponyfill`, I'm no longer convinced that it'd be a good idea. The reason is that if we actually want to properly support CSS variables, then that functionality should be available in *all* of our CSS files. Note in particular the `pdf_viewer.css` file that's built as part of the `COMPONENTS` target, in which case I really cannot see how a rewrite-at-the-client solution would ever be guaranteed to always work correctly and without accidentally touching other CSS in the surrounding application. All-in-all, simply re-writing the CSS variables at build-time seems much easier and is thus the approach taken in this patch; courtesy of https://github.com/MadLittleMods/postcss-css-variables By using its `preserve` option, the built files will thus include *both* a fallback and a modern `var(...)` format[1]. As a proof-of-concept this patch removes a couple of manually added fallback values, and converts an additional sidebar related property to use a CSS variable. --- [1] Comparing the `master` branch with this patch, when using `gulp generic`, produces the following diff for the built `web/viewer.css` file: ```diff @@ -408,6 +408,7 @@ :root { --sidebar-width: 200px; + --sidebar-transition-duration: 200ms; } * { @@ -550,27 +551,28 @@ position: absolute; top: 32px; bottom: 0; - width: 200px; /* Here, and elsewhere below, keep the constant value for compatibility - with older browsers that lack support for CSS variables. */ + width: 200px; width: var(--sidebar-width); visibility: hidden; z-index: 100; border-top: 1px solid rgba(51, 51, 51, 1); -webkit-transition-duration: 200ms; transition-duration: 200ms; + -webkit-transition-duration: var(--sidebar-transition-duration); + transition-duration: var(--sidebar-transition-duration); -webkit-transition-timing-function: ease; transition-timing-function: ease; } html[dir='ltr'] #sidebarContainer { -webkit-transition-property: left; transition-property: left; - left: -200px; + left: calc(-1 * 200px); left: calc(-1 * var(--sidebar-width)); } html[dir='rtl'] #sidebarContainer { -webkit-transition-property: right; transition-property: right; - right: -200px; + right: calc(-1 * 200px); right: calc(-1 * var(--sidebar-width)); } @@ -640,6 +642,8 @@ #viewerContainer:not(.pdfPresentationMode) { -webkit-transition-duration: 200ms; transition-duration: 200ms; + -webkit-transition-duration: var(--sidebar-transition-duration); + transition-duration: var(--sidebar-transition-duration); -webkit-transition-timing-function: ease; transition-timing-function: ease; } ```
PDF.js 
PDF.js is a Portable Document Format (PDF) viewer that is built with HTML5.
PDF.js is community-driven and supported by Mozilla Labs. Our goal is to create a general-purpose, web standards-based platform for parsing and rendering PDFs.
Contributing
PDF.js is an open source project and always looking for more contributors. To get involved, visit:
- Issue Reporting Guide
- Code Contribution Guide
- Frequently Asked Questions
- Good Beginner Bugs
- Projects
Feel free to stop by #pdfjs on irc.mozilla.org for questions or guidance.
Getting Started
Online demo
Browser Extensions
Firefox
PDF.js is built into version 19+ of Firefox.
Chrome
- The official extension for Chrome can be installed from the Chrome Web Store. This extension is maintained by @Rob--W.
- Build Your Own - Get the code as explained below and issue
gulp chromium. Then open Chrome, go toTools > Extensionand load the (unpackaged) extension from the directorybuild/chromium.
Getting the Code
To get a local copy of the current code, clone it using git:
$ git clone https://github.com/mozilla/pdf.js.git
$ cd pdf.js
Next, install Node.js via the official package or via nvm. You need to install the gulp package globally (see also gulp's getting started):
$ npm install -g gulp-cli
If everything worked out, install all dependencies for PDF.js:
$ npm install
Finally, you need to start a local web server as some browsers do not allow opening
PDF files using a file:// URL. Run:
$ gulp server
and then you can open:
Please keep in mind that this requires an ES6 compatible browser; refer to Building PDF.js for usage with older browsers.
It is also possible to view all test PDF files on the right side by opening:
Online setup with a single click
It's recommended to follow [Getting the Code] above, however you can also use Gitpod (a free online VS Code like IDE). With a single click it will launch a ready to use workspace, with all the dependencies pre-installed and the web server running, so that you can start coding straight away.
Building PDF.js
In order to bundle all src/ files into two production scripts and build the generic
viewer, run:
$ gulp generic
This will generate pdf.js and pdf.worker.js in the build/generic/build/ directory.
Both scripts are needed but only pdf.js needs to be included since pdf.worker.js will
be loaded by pdf.js. The PDF.js files are large and should be minified for production.
Using PDF.js in a web application
To use PDF.js in a web application you can choose to use a pre-built version of the library
or to build it from source. We supply pre-built versions for usage with NPM and Bower under
the pdfjs-dist name. For more information and examples please refer to the
wiki page on this subject.
Including via a CDN
PDF.js is hosted on several free CDNs:
- https://www.jsdelivr.com/package/npm/pdfjs-dist
- https://cdnjs.com/libraries/pdf.js
- https://unpkg.com/pdfjs-dist/
Learning
You can play with the PDF.js API directly from your browser using the live demos below:
More examples can be found in the examples folder. Some of them are using the pdfjs-dist package, which can be built and installed in this repo directory via gulp dist-install command.
For an introduction to the PDF.js code, check out the presentation by our contributor Julian Viereck:
More learning resources can be found at:
The API documentation can be found at:
Questions
Check out our FAQs and get answers to common questions:
Talk to us on IRC (Internet Relay Chat):
- #pdfjs on irc.mozilla.org
File an issue:
Follow us on twitter: @pdfjs