From WebOS Internals
Call for hackers
From destinal July 11 09 -- This is very much a work in progress. If you are interested in being part of the effort to get a graphical terminal (and any number of other GUI applications) working on the Pre, please contact me at destinal on #webos-internals or email me at firstname.lastname@example.org. --destinal
Browser plugins are located a directory defined in the PluginsPath directive in /etc/palm/browser.conf. The default path is shown below.
browser.conf: PluginsEnabled=true browser.conf: PluginsPath=/usr/lib/BrowserPlugins
Browser plugins are ELF-format shared libraries with the standard .so extension.
To be more specific, in fact, webOS browser plugins use the NPAPI specification common in WebKit and Gecko-based browsers.
For information on how to create an NPAPI compliant plugin, see Mozilla Plugin Documentation
root@castle:/usr/lib/BrowserPlugins# ls *.so BrowserAdapter.so MAPartsAdapter.so PDFAdapter.so LunaMediaAdapter.so OfficeAdapter.so TnAdapter.so
Upon Luna start, all shared libraries in the plugins directory are loaded and registered based on the MIME type they return in their public function NP_GetMIMEDescription()
Stock plugins by MIME type
root@castle:/# grep x- /usr/lib/BrowserPlugins/* /usr/lib/BrowserPlugins/BrowserAdapter.so:application/x-palm-browser /usr/lib/BrowserPlugins/LunaMediaAdapter.so:application/x-palm-media;media;Media File /usr/lib/BrowserPlugins/MAPartsAdapter.so:application/x-motionapps-partsadapter /usr/lib/BrowserPlugins/OfficeAdapter.so:application/x-palm-officeadapter /usr/lib/BrowserPlugins/PDFAdapter.so:application/x-palm-pdfadapter /usr/lib/BrowserPlugins/TnAdapter.so:application/x-navigation
Building a working browser plugin (using the basicplugin sample)
Getting the code
BasicPlugin is located in the webos-internals applications repository. A sample webOS / mojo application called helloplugin which embeds it is also available there.
git clone git://gitorious.org/webos-internals/applications.git
Ensure you have required libraries
This depends on your linux distro. On ubuntu, you will need build-essential, libglib2.0-dev, and libx11-dev:
sudo apt-get install build-essential libglib2.0-dev libx11-dev
Building the plugin (basicplugin.so)
cd applications/basicplugin make
Installing the plugin
Copy basicplugin.so to your pre or emulator into the directory /usr/lib/BrowserPlugins.
Installing the mojo app to call it
Copy the directory applications/org.webosinternals.helloplugin to your applications directory on your pre or emulator (/var/usr/palm/applications)
Rescan Luna packages or reboot to get an icon to launch it.
Running the plugin
Simply click the "Hello Plugin" link in the emulator.
If everything worked, you'll have a blue card.
A blue card?
Later versions of the sample plugin will do something more exciting, but that's not the point.
More importantly, check out the code, and use it as a template to create your own browser plugins.
Also check out the mojo code for more advanced plugin-based-apps to see the huge amounts of event forwarding code required for a proper app
Things to try next
Write useful plugins
Enhance mojo app to transmit keyboard, pen, and other events.
Plugins vs extensions
More on plugins seems to be at:
About This stuff so far: destinal thanks to:
- bpadalino (help in debugging)
- mdklein (npapi, npsimple ideas)