Delphi Chromium Embedded And Loop

Question

I have a small problem with Chrome embedded in Delphi.
I would like to get the text of the page loaded from a list of URLs in ListBox (loop).

It seems easy ! My code looks like :

for i := 0 to Form1.ListBox1.Items.Count - 1 do
begin
  // Load URL
  Form1.Chromium1.Browser.MainFrame.LoadUrl(Form1.ListBox1.Items[i]);

  // Put text in StringList
  s := TStringList.Create;
  s.Text := Trim(Form1.Chromium1.Browser.MainFrame.Text);

  // Save with random name
  s.SaveToFile(ExtractFilePath(Application.Exename) +
    IntToStr(RandomRange(1000, 9999)) + '.txt');
end;

The loop works, but take just 1-2 seconds and files saved are empty...
In reality the loop is finished before that pages are loaded :S
It should wait the end of page loading.

Does someone have an idea about that ?
Thanks in advance ! :)

Beny