Method for actively calling js functions using the npapi plug-in

I have read many articles and introduced the function methods of js callback plug-ins, but there are few examples of the plug-ins actively calling js functions.

Http://www.codeproject.com/Articles/92787/Working-on-an-NPAPI-browser-plugin

The code linked above is a good example of a function in the browser callback plug-in, there is no codeproject account, please move here download: http://download.csdn.net/detail/yzsyb/5814095

(Sorry, I forgot to set it to free download during the upload process. Now I need a point. I have to apply for a part to delete the resource. If you are in trouble, just one point! Sorry)

In the original example, let me talk about it a little bit:

In the Codeproject.html file: <inputvalue = "Add Field 1 and 2" onclick = "Add ()" type = "button"> is a button, and the button event is defined as Add (), and Add () is:

function Add(){         try         {                          if(CheckBrowser() ) return;                   vara1 = document.getElementById("f1").value;                   vara2 = document.getElementById("f2").value;                   varres = PLUGIN.Add(a1,a2);//we can also add numbers and strings (because of theplugin implementation)                   alert("Plugin Added result is: " + res );         }         catch(err) { alert(err); }}

Var res = PLUGIN. Add (a1, a2); the plug-in function is called, in plugin. cpp, as shown below:

ScriptablePluginObject::Invoke(NPIdentifiername, const NPVariant *args, uint32_t argCount, NPVariant *result){         //kk          char*pFunc = NPN_UTF8FromIdentifier(name);                           if(!strcmp( "Add", pFunc ) )         {                   intsum = 0;                    for(unsigned int i = 0; i < argCount; i++ )                   {                            if(args[i].type == NPVariantType_Int32 )                            {                                     sum+= args[i].value.intValue;                            }                            elseif( args[i].type == NPVariantType_String )                            {                                     CNPStrings(args[i].value.stringValue);                                     sum+= atoi( s );                            }                            elsereturn false;//an error happenend                    }                   //valuefor GUI output                   sprintf(m_szTextGui, "Sum = %ld", sum );                   //triggering                   ::InvalidateRect(m_hWnd, 0, true );                   //niceand handy little helpers, there are more of it                   INT32_TO_NPVARIANT(sum,*result);                   returntrue;         }…………}

Http://www.m0interactive.com/archives/2010/10/21/how_to_communicate_back_to_javascript_from_npapi_plugin.html

This article describes how to call js from the npapi plug-in. I also learned from this article. Thanks to the original author.

 

The following describes how to call js functions from the plug-in.

The download link of my code is at the end of the article.

PS: the code I added is between // smiler and /// smiler.

First, I created a Button in the plug-in window)

case WM_CREATE:        {        CreateWindow(TEXT("BUTTON"),TEXT("Hello"),            WS_VISIBLE|WS_CHILD|BS_FLAT,            10,120,            40,40, hWnd,            NULL,0,0);        break;                   }

Button event:

Case wm_command: {wordncode = hiword (wparam); wordcontrol = loword (wparam); If (ncode = bn_clicked) {cplugin * P = (cplugin *) getwindowlongptr (hwnd, gwlp_userdata); P-> Hello (); // call the hello function of the plug-in} break ;}

Hello () function:

Void CPlugin: hello () {char * message1 = "This is a hello"; char * message2 = "from NPAPI plugin"; NPP npp = (NPP) m_pNPInstance; NPObject * npwindow = NULL; NPError ret = NPN_GetValue (npp, npnv1_wnpobject, & npwindow); if (ret! = NPERR_NO_ERROR) {MessageBox (NULL, ("sf"), ("prompt"), MB_ OK); return ;}// Get windowobject. NPVariantwindowVar; NPIdentifierwinID = NPN_GetStringIdentifier ("window"); bool bRet = NPN_GetProperty (npp, npwindow, winID, & windowVar); if (! BRet) {MessageBox (NULL, ("Callback"), ("prompt"), MB_ OK); NPN_ReleaseObject (npwindow); return;} NPObject * window = NPVARIANT_TO_OBJECT (windowVar ); // Invoke "callback_hello" NPVarianttype1, type2; Messages (message1, type1); Messages (message2, type2); NPVariantargs [] = {type1, type2}; NPVariantvoidResponse; NPIdentifierfuncID = NPN_GetStringIdentifier ("callback _ Hello "); bRet = NPN_Invoke (npp, window, funcID, args, 2, & voidResponse); if (! BRet) {MessageBox (NULL, ("invokefailed"), ("prompt"), MB_ OK); return ;}// clean up NPN_ReleaseObject (npwindow); NPN_ReleaseVariantValue (& windowVar ); NPN_ReleaseVariantValue (& voidResponse );}

In the above Code:

Bret = npn_invoke (NPP, window, funcid, argS, 2, & voidresponse); calls the callback_hello function in Js.

 

Test the callback_hello function in the page npruntime_demo.html:

function callback_hello(hellotext1,hellotext2){ alert(hellotext1); alert(hellotext2);}

Shows the running result:

Click "hello:

My code download link: http://download.csdn.net/detail/yzsyb/5814395