Hi Mohamed,

Thanks for the great article!

I'm kind of interested in sending an event to the browser to be handled within the JavaScript code. i.e. when the plugin has finished doing something, I want the JavaScript to display a popup on the page?

Thanks in advance.

I might write an article on that, asynchronous NPAPI communication, it is pretty cool :)

thank you Mohamed for the article, it has been useful.

i'am doing a web application based on the npapi, it looks like i need the function NPN_PluginThreadAsyncCall to implement asynchronous calls.

i searched for a tutorial how to use this function but in vain.

thank you for your help

/**

in this example i defined a button in an HTML page that calls this plugin. this button

calls the function asynchTest(). this function simulates a process that lasts a long time.

in an ordinary case if a process takes a long time to execute, it will block the mmi.

to avoid this, i used the function NPN_PluginThreadAsyncCall. However, mmi behavior is the same.

it is blocked in these 5 seconds (clicking on another button does nothing).

*/

void myfunc () //function called from mythread()

{

sleep(5);//simulate a process that takes a long time to be executed

npnfuncs->geturl(inst, "javascript:jsFunc(0)", "_self");//call a js function which alert a message

}

void * mythread (void* data)//function called from asynchTest()

{

NPP instance = (NPP) data;//plugin instance

//structure npnfuncs contains a certain number of the browser functions

//among these functions NPN_PluginThreadAsyncCall

npnfuncs->pluginthreadasynccall (instance, myfunc, NULL);//async call of myfunc in this thread

return NULL;

}

void asynchTest()//function called from invoke()

{

pthread_t thread1;//thread calling function mythread

int iret1 = pthread_create( &thread1, NULL, mythread, (void*) inst);

}

static bool invoke(NPObject* obj, NPIdentifier methodName, const NPVariant *args, uint32_t argCount, NPVariant *result) //npapi function that executes methods passed as argument

{

char *name = npnfuncs->utf8fromidentifier(methodName);//in this case methodName is asynchTest (from js)

if(!strcmp(name, "asynchTest")) {

asynchTest();//call asynchTest

return true;

}

}

what is wrong with this code ? Is this the correct behavior of the plugin ? thank you for your help

Hi Mohamed,

Thanks for the wonderful article! I've just started learning NPAPI recently, my question is how to pass an unsigned char array from the plugin to my javascript, I spent hours searching but cannot find any helpful info, any help from you will be appreciated, cheers :)

Steve

Thank you very much Mohamed, I'll give it a go and let you the result.

Cheers,

Steve

Jingjing: no problem :) I realized that I have done it in an extension I did last month. If you want more info, you can take a look how its done on one of my NPAPI Haptics extensions:

github.com/mohamedmansour/haptics-chrome-extension/blob/master/source/haptics_service.cc#L114

Basically, I want to fetch the device position into a 3 dimensional point, hence represented in an array.

If you have more question, let me know! And thanks for getting back to me with your solution :)

Hey dude,

Can u please share a book on step by step procedure to learn NPAPI. I didn't find any ebook available.

Can u please elaborate the step-by-step process to load npapi files from javsscript.

Thanks,

Akshay Sahu