Enumerating DOM nodes in TChromium

Question

I am trying to enumerate DOM nodes using the following code (under XE2).

I have borrowed most of this from answers given here in SO, but for some reason it's not doing anything.

IOW, ProcessDOM() is not ever getting called.

And, I am at my wits end.

Could someone show me what I am doing wrong here.

Thanks in advance.

procedure ProcessNode(ANode: ICefDomNode);
var
  Node1: ICefDomNode;
begin
  if Assigned(ANode) then begin
    Node1 := ANode.FirstChild;
    while Assigned(Node1) do begin
      {Do stuff with node}
      ProcessNode(Node1);
      Node1 := Node1.NextSibling;
    end;
  end;
end;

procedure ProcessDOM(const ADocument: ICefDomDocument);
begin
  ProcessNode(ADocument.Body);
end;

procedure TMainForm.Chrome1LoadEnd(Sender: TObject; const ABrowser: ICefABrowser; const AFrame: ICefAFrame; AStatus: Integer);
begin
  if Assigned(AFrame) then AFrame.VisitDomProc(ProcessDOM);
end;

Answer 1

I had the same problem and I used the demo guiclient it comes with dcef3. With the following it works.

type TCustomRenderProcessHandler = class(TCefRenderProcessHandlerOwn)
  protected
    function OnProcessMessageReceived(const browser: ICefBrowser; sourceProcess: TCefProcessId; const message: ICefProcessMessage): Boolean; override;
end;

Chromium1.browser.SendProcessMessage(PID_RENDERER, TCefProcessMessageRef.New('visitdom')); 

function TCustomRenderProcessHandler.OnProcessMessageReceived(browser: ICefBrowser; sourceProcess: TCefProcessId; message: ICefProcessMessage): Boolean;
begin 
  if (message.Name = 'visitdom') then begin
    browser.MainFrame.VisitDomProc(
        procedure(const doc: ICefDomDocument) 
        begin
          ProcessNode(Doc.Body);
        end);
    Result := True;
  end; 
end;

initialization
  CefRenderProcessHandler := TCustomRenderProcessHandler.Create;