[webkit-dev] safari extension script loading within injected file

[Nick Guenther]

Cluestick (or n00b question): What's 'document' within the extension scope?

----- Original message -----
> Hello list,
> 
> I am seeing some behavior that I cannot explain with a safari 5
> extension. First, let me show a bit of code that works as expected
> outside the extension environment.   This loads jQuery from javascript:
> 
> (function(){
>     var node = document.createElement('script');
>     node.onload = function(){
>         if(typeof(jQuery) == 'undefined'){
>             console.log("fail: jQuery is undefined");
>         }
>         else{
>             console.log("success: jQuery is defined");
>         }
>     };
>     node.async = "async";
>     node.type = "text/javascript";
>     node.src =
> "http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js" 
> document.getElementsByTagName('head')[0].appendChild(node); })();
> 
> 
> If I open the Safari Console and load a page with this bit of code, I see
> "success: jQuery is defined".   So far so good.   Next, I'll copy that
> exact chunk of code into a file that my safari extension injects,
> injected.js:
> 
> function messageHandler(event){
>     if(event.name === "show"){
>         (function(){
>             var node = document.createElement('script');
>             node.onload = function(){
>                 if(typeof(jQuery) == 'undefined'){
>                     console.log("fail: jQuery is undefined");
>                 }
>                 else{
>                     console.log("success: jQuery is defined");
>                 }
>             };
>             node.async = "async";
>             node.type = "text/javascript";
>             node.src = "
> http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"
>             document.getElementsByTagName('head')[0].appendChild(node);
>         })();
>     }
> }
> 
> safari.self.addEventListener("message",messageHandler,false);
> 
> A tiny bit about my extension: when the user clicks a toolbar button it
> sends the 'show' message to the injected script.   When that happens, I
> see "fail: jQuery is undefined" logged to the console.   If I put a
> breakpoint inside the onload callback, I can verify that this is the
> case.   However, once I hit continue in the debugger, jQuery is defined! 
> It is as if jQuery is not defined in the scope of my extension when I
> load it with this method. Does that make sense?
> 
> In summary, what would cause the loading method used above to work
> outside the safari extension environment, but not inside it?
> 
> Thanks,
> Lou Zell