Cannot set JS object value

[CephaluS]

Hello. I want to write/read data between C++ and a JS object using the accessor scheme (I've implemented CefV8Accessor following the documentation). This is the code I'm using in OnContextCreated:

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global_obj = context->GetGlobal();
accessor = new MyV8Accesor();
obj = CefV8Value::CreateObject(accessor, NULL);
global_obj->SetValue("myval", obj, V8_PROPERTY_ATTRIBUTE_NONE);


I guess that code is correct in order to initialize the structure.
At this point I display the value of the object in the browser with alert(myval) JS expression, that returns '[object Object]'.

To set the value of the object I've tried the following expression unsuccessfully:

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obj->SetValue("Hello world...", V8_ACCESS_CONTROL_DEFAULT, V8_PROPERTY_ATTRIBUTE_NONE);


But I'm blatantly failing at this because alert(..) keeps returning '[object Object]'.
I've tried also to use accessor->Set / accessor->Get unsuccessfully as well.

What code do I lack in order to set/get the value of the object?.

Thanks in advance.

[magreenblatt]

In your example "myval" is an object. So if you want to trigger the accessor callback you need to use something like "myval.myproperty".

[CephaluS]

Thanks for your help. I've finally managed to initialize an object that triggers the accessor callbacks in OnContextCreated().

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//init
CefRefPtr<CefV8Accessor> accessor = new GuiCefV8Accesor();
CefRefPtr<CefV8Value> obj = CefV8Value::CreateObject(accessor, NULL);
obj->SetValue("myval", V8_ACCESS_CONTROL_DEFAULT, V8_PROPERTY_ATTRIBUTE_NONE);

// set
obj->SetValue("myval", CefV8Value::CreateString("Hello world..."), V8_PROPERTY_ATTRIBUTE_NONE);


But the object does't exist in the window (JS alert(myval) command reports "Uncaught ReferenceError: myval is not defined")

I can get the frame window object using context->GetGlobal() but I cannot find a way to link my object to it.

Thank you.

[magreenblatt]

You need to add your object to the window object and then use alert(window.myval.myproperty) where myval is your object.

[CephaluS]

Marhsall, thank you for your quick reply. Adding or linking an object to another object is precisely what I need. I've been reading for hours but I cannot find the way to do it in the documentation or examples.

I've tried this (look at the last line, in my attempt to add and object to another object) but it doesn't work:

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global_obj = context->GetGlobal();

CefRefPtr<CefV8Accessor> accessor = new MyV8Accesor();
CefRefPtr<CefV8Value> obj = CefV8Value::CreateObject(accessor, NULL);
obj->SetValue("myproperty", V8_ACCESS_CONTROL_DEFAULT, V8_PROPERTY_ATTRIBUTE_NONE);
obj->SetValue("myproperty", CefV8Value::CreateString("Hello world..."), V8_PROPERTY_ATTRIBUTE_NONE);
   
global_obj->SetValue("myval", obj, V8_PROPERTY_ATTRIBUTE_NONE);

Thank you.

[Czarek]

You should check return values of any functions you call to see if they executed successfully. This includes CreateObject and SetValue.

[CephaluS]

Hi Czarek, Thanks for your hint... actually that last line worked. I just had to change label id in MyV8Accesor code.

Thanks Marshall and you for your patience and amazing job and help!