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TQt Netscape Plugin Extension

The TQt Netscape Plugin software makes it easy to write browser plugins that can be used on both Unix/Linux and MS-Windows, in Netscape, Mozilla, and any other web browser supporting Netscape's LiveConnect protocol. Modern versions of MSIE do not support this protocol.

Information

The Netscape Plugin Extension consists of the follow classes:

• TQNPlugin
• TQNPInstance
• TQNPWidget
• TQNPStream

How-to

1. Download the Plugin SDK from Netscape, and copy the following files from there to $TQTDIR/extensions/nsplugin/src
   • common/npwin.cpp
   • common/npunix.c
   • include/npapi.h
   • include/npupp.h
   • include/jri.h
   • include/jri_md.h
   • include/jritypes.h
2. Build the Netscape Plugin extension library, found in the extensions/nsplugin/src directory of your TQt distribution. This produces a static library to be linked with your plugin code.
3. Read the plugin class documentation, and examine the example plugins.
4. Do most of your development as a stand-alone TQt application - debugging Netscape Plugins is cumbersome. You may want to use signal(2) in your plugin to enable core-dumps if your browser disables them.
5. Note the platform-specific build steps below.
6. Read about the raw plugin interface in Netscape's handbook.
7. If files viewed by a plugin are provided by an HTTP server (using a http://... URL) then the server must be configured to send the correct MIME type for the file, e.g. by editing Apache's mime.types file. If the files are viewed via a //... URL, then the browser will use the filename extension to decide the file type (and hence the plugin to load) - the user may need to set the filename extension in the Helpers or Applications section of their browser preferences.

Building under X11

• The Makefiles in the examples are appropriate for UNIX/X11.
• The user must install the resulting Shared Object in the Plugins directory of the browser.

Building under Windows

• For Netscape plugins to work, TQt needs to be in the system DLL path or be compiled into the plugin as a static library.
• Plugins must be named npname.dll, or the browser will ignore them.
• The link step must include:
  • /def:name.def
  • /dll
  • a compiled resource file defining the file/MIME types accepted by the plugin.
• The user must install the resulting DLL in the Plugins directory of the browser.

Known Bugs and Limitations

The TQt-based LiveConnect Plugin binding code has a number of bugs and limitations, but is sufficiently stable for many production applications.

• Keyboard input only works in secondary windows (e.g. dialogs created by the plugin).
• You should not expect modality between the plugin and the browser to work.
• Netscape 4.78 on Unix/X11 tends to terminate with a bus error.
• Opaque resize behaviour is erratic due to browser behavior.