How can I update the status messages in Firefox from any thread?

Question

I encountered a problem with updating the status message on Firefox from a Plugin code.

As the documentation says calling NPN_Status works only when called from the main thread. My requirement is to update the status from any thread within the Firefox process.

Any help would be appreciated!

score 1 · Accepted Answer · answered Jun 24 '09 at 14:25

1

You can't update it from any thread because that would violate some of the threadsafety rules. You will have to proxy your update back to the main thread.

answered Jun 24 '09 at 14:25

sdwilsh

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could you provide me with any example code / further details on how this proxy thing could be achieved ? – atVelu Jun 25 '09 at 04:48
You might be able to use https://developer.mozilla.org/en/NPN_PluginThreadAsyncCall, but I'm not certain. – sdwilsh Jun 26 '09 at 20:07

Georg Fritzsche · Answer 2 · 2010-04-11T00:56:51.690

Like sdwilsh said, you are to call the NPN_*-functions only from the main thread. NPN_PluginThreadAsyncCall was only introduced in Gecko 1.9 and isn't supported in all current browsers.

Workarounds depend on the platform:

on Windows subclass the window your plugin receives, post/send messages to it and invoke the call from the handling window process
on Mac with Cocoa you can use e.g. performSelectorOnMainThread
on Mac with Carbon you can use invoke the calls on the null event
... etc.

How can I update the status messages in Firefox from any thread?

2 Answers2