Delphi XE3 and TChromium

Question

Make out the work with a component in Delphi XE3 TChromium need to get to the content of the page is loaded forums found examples of working code:

procedure DoWork (const doc: ICefDomDocument);
var
  q: ICefDomNode;
begin
  q: = doc.GetElementById ('q');
  if Assigned (q) then q.SetElementAttribute ('value', 'Hello, world');
end;

procedure actDomExecute;
var
  q: ICefDomNode;
begin
   crm.Browser.MainFrame.VisitDomProc (DoWork);
end;

But the debugger somehow bypasses execution of an obstinately DoWork. In what may be a catch?

Depends on version of Chromium you're using. As far as I remember in a few versions, DOM iteration didn't work at all. — TLama
If we're talking about CEF1 wrapper (since there is also CEF3 wrapper), then I'm afraid you've hit just this issue (the same seems to happen in CEF3 as well). You might try some older version of CEF1 (can't tell you which is the latest, where this worked though) and check what has changed since that version. — TLama

Kapytanhook Kapytanhook · Accepted Answer · 2013-04-06T17:20:20

I got tChromium to work under Delphi 7, it should all work the same.

There are the steps I took to read elements from the DOM

First I got a wrapper from this project: https://code.google.com/p/delphichromiumembedded/downloads/detail?name=dcef-r306.7z&can=2&q=

There is also one for XE2, would not take much to convert that to XE3, if you need help with that I will gladly help on request.

Then declare a begin and end in the tchromium

procedure TMainForm.crmLoadStart(Sender: TObject;   const browser: ICefBrowser; const frame: ICefFrame); begin   
  if (browser <> nil) and (browser.GetWindowHandle = crm.BrowserHandle) and ((frame = nil) or (frame.IsMain)) then FLoading := True; 
end;

,

procedure TMainForm.crmLoadEnd(Sender: TObject; const browser: ICefBrowser; const frame: ICefFrame; httpStatusCode: Integer; out Result: Boolean);
begin
  if (browser <> nil) and (browser.GetWindowHandle = crm.BrowserHandle) and ((frame = nil) or (frame.IsMain)) then begin
    FLoading := False;
    // see if loaded
    while(httpStatusCode <> 200) do begin
      Application.ProcessMessages;
      Sleep(50);
    end;
    browser.GetMainFrame.VisitDomProc(DomProc);
  end;
end;

Declare a procedure called domproc like so:

procedure DomProc(const Doc: ICefDomDocument);
var
  Node: ICefDomNode;
begin
  url := Doc.BaseUrl;
  if(url='www.goodwebsite.com') then // check if it is the right page and not add
    Node := Doc.Body.Document.GetElementById('idofwhatyouarelookingfor');
  Node.SetElementAttribute('value','Hello world :D');
end;

That was the most reliable way i have found so far, you need to make sure the page is well loaded and that you are getting the dom for the right frame.

Hope it helps you, make sure to check out the example code in the download link above, that helped me out a lot.

Have fun coding, Delphi rocks!

Delphi XE3 and TChromium

1 Answers