c++builder - TChromium (RAD Studio, C++ Builder): how to use VisitDom and other similar methods? -

i need write windows application uses browser component in it. chose rad studio's c++ builder because have used in past, however, i'm not experienced in c++ programming in web-dev (i'm web-developer: js, php, etc...), so, encountered problems realization of project. hope, i'm missing basic c++ professional specialist solve quick thought.

built-in twebbroswer component has many disadvantages, made decision use chromium (https://github.com/hgourvest/dcef3). took time install , make work not in delphi, in c++ builder well, however, i've got project tchromium in form compiles , works fine @ moment: can navigate pages, execute js , more.

nevertheless, there 1 problem still cannot solve: accessing document's dom. in google search results found nothing helpful: 1 topic same problem , no answers (http://www.cyberforum.ru/cpp-builder/thread996496.html) , documentation.

in documentation has been said have use visitdom method purpose, have no idea how in c++ builder.

in c++ demo: https://code.google.com/p/chromiumembedded/source/browse/trunk/cef3/tests/cefclient/dom_test.cpp?r=689 see following code:

class clientdomvisitor : public cefdomvisitor {  public:   clientdomvisitor() {   }    virtual void visit(cefrefptr<cefdomdocument> document) override {     // register click listener button.     cefrefptr<cefdomnode> button = document->getelementbyid("button");     assert(button.get());     button->addeventlistener("click", new clientdomeventlistener(), false);   }    implement_refcounting(clientdomvisitor); }; 

then, in visitdom method:

visitdom(new clientdomvisitor) 

when i'm trying compile piece of code, errors occur (in c++ builder), such as:

[bcc32 error] unit1.cpp(184): e2303 type name expected 

later, i've tryied use advice topic (not domvisitor - stringvisitor, think, if make 1 of them work have no problems second one): https://groups.google.com/forum/#!msg/delphichromiumembedded/dckdckoclzw/-zguxoutxa4j written in delphi, i'm not sure if correctly translated code c++.

in unit1.h, i've added icefstringvisitor tform1 discussed , added visit method private declaration section:

    class tform1 : public tform, icefstringvisitor     {     __published:    // ide-managed components // ... i've hide part of code, nothing useful here ...         tchromium *chromium1;         void __fastcall chromium1beforebrowse(tobject *sender, const icefbrowser *browser,               const icefframe *frame, const icefrequest *request, bool isredirect,               bool result);         void __fastcall chromium1loadend(tobject *sender, const icefbrowser *browser, const icefframe *frame,               int httpstatuscode);     private:    // user declarations         void __fastcall visit(const unicodestring str);     public:     // user declarations          __fastcall tform1(tcomponent* owner);     }; 

in unit1.cpp i've added:

void __fastcall tform1::visit(const unicodestring str) {    showmessage(str); } void __fastcall tform1::chromium1loadend(tobject *sender, const icefbrowser *browser, const icefframe *frame, int httpstatuscode) {    icefframe * ncframe = const_cast<icefframe *>(frame);    // doesn't compile without const_cast    ncframe->getsource(this);     } 

this code compiles , runs, i'm getting error , application terminates:

pure virtual function called 

i'm tired struggling this. can experienced advice me how use of these visitdom, viewsource , other methods in rad studio c++ builder? in delpi, see, rather easy.

p.s. if somehow, in ceflib.hpp found following declaration:

__interface icefdomvisitor; typedef system::delphiinterface<icefdomvisitor> _di_icefdomvisitor; __interface  interface_uuid("{8fd3d3a6-ea3a-4a72-8501-0276bd5c3d1d}") icefframe  : public icefbase  {  public:     virtual bool __fastcall isvalid(void) = 0 ;     virtual void __fastcall undo(void) = 0 ;     virtual void __fastcall redo(void) = 0 ;     virtual void __fastcall cut(void) = 0 ;     virtual void __fastcall copy(void) = 0 ;     virtual void __fastcall paste(void) = 0 ;     virtual void __fastcall del(void) = 0 ;     virtual void __fastcall selectall(void) = 0 ;     virtual void __fastcall viewsource(void) = 0 ;     virtual void __fastcall getsource(const _di_icefstringvisitor visitor) = 0 ;     virtual void __fastcall getsourceproc(const _di_tcefstringvisitorproc proc) = 0 ;     virtual void __fastcall gettext(const _di_icefstringvisitor visitor) = 0 ;     virtual void __fastcall gettextproc(const _di_tcefstringvisitorproc proc) = 0 ;     virtual void __fastcall loadrequest(const _di_icefrequest request) = 0 ;     virtual void __fastcall loadurl(const ustring url) = 0 ;     virtual void __fastcall loadstring(const ustring str, const ustring url) = 0 ;     virtual void __fastcall executejavascript(const ustring code, const ustring scripturl, int startline) = 0 ;     virtual bool __fastcall ismain(void) = 0 ;     virtual bool __fastcall isfocused(void) = 0 ;     virtual ustring __fastcall getname(void) = 0 ;     virtual __int64 __fastcall getidentifier(void) = 0 ;     virtual _di_icefframe __fastcall getparent(void) = 0 ;     virtual ustring __fastcall geturl(void) = 0 ;     virtual _di_icefbrowser __fastcall getbrowser(void) = 0 ;     virtual _di_icefv8context __fastcall getv8context(void) = 0 ;     virtual void __fastcall visitdom(const _di_icefdomvisitor visitor) = 0 ;     virtual void __fastcall visitdomproc(const _di_tcefdomvisitorproc proc) = 0 ;     __property ustring name = {read=getname};     __property ustring url = {read=geturl};     __property _di_icefbrowser browser = {read=getbrowser};     __property _di_icefframe parent = {read=getparent}; };