Dynamic Creating TChromium

[salvadordf]

Hi,

The TChromium and TFMXChromium components are created asynchronously.

It's necessary to wait until the TChromium.OnAfterCreated event is triggered before handling the browser. Take a look at the SimpleBrowser2 demo and you will see that it sends a CEF_AFTERCREATED message from the TChromium.OnAfterCreated event to enable the GUI and load the first website.

You can also set TChromium.DefaultUrl before calling TChromium.CreateBrowser to load the default URL as soon as the browser is initialized.

Also remember that you can't call TChromium.CreateBrowser before GlobalCEFApp.GlobalContextInitialized is set to TRUE. The demos have a TTimer to retry TChromium.CreateBrowser until GlobalCEFApp.GlobalContextInitialized is TRUE.

Please read the code comments in the SimpleBrowser2 demo for more information.

[tad.chen]

Hi,

I create the TChromium in OSR mode dynamically, but the browser crashed in libcef.dll.

Code: Select all

var
  FChrmosr: TChromium;

procedure TForm1.FormCreate(Sender: TObject);
begin
  FChrmosr:=TChromium.Create(Self);
  FChrmosr.DefaultUrl:='about:blank';
  FChrmosr.OnAfterCreated:=chrmosrAfterCreated;
end;

procedure TForm1.FormShow(Sender: TObject);
begin
  if FChrmosr.Initialized then
    begin
      FChrmosr.WasHidden(False);
      FChrmosr.SendFocusEvent(True);
    end
   else
    begin
      // opaque white background color
      FChrmosr.Options.BackgroundColor := CefColorSetARGB($FF, $FF, $FF, $FF);

      if FChrmosr.CreateBrowser(nil, '') then
        FChrmosr.InitializeDragAndDrop(Panel1)
       else
        Timer1.Enabled := True;
    end;
  //
end;

I debug the code above and see that CreateBrowser fuction return true and InitializeDragAndDrop is executed.

But after that the program halt in libcef.dll and crash.

At this time, the OnAfterCreated isn't triggered because the break point in chrmosrAfterCreated is not executed.

I use Win7 & Delphi 10.3 communication edition.

[salvadordf]

Please, make sure you are using the CEF binaries from the "Release" and "Resources" directories. Never use the binaries from the "Debug" directory.

If there is no problem with the CEF binaries then create an screenshot of this crash showing the "Call Stack" window.

The PopupBrowser demo creates browsers in OSR mode at run time. It's a complex demo because it has to create popup windows but perhaps you can compare it to your app.

Edit : I just checked the PopupBrowser demo and it crashes too. I'll take a look this weekend.

[tad.chen]

I do use the wrong CEF binaries which come from "debug" directory. But after I change to "release" directory, The program crashes too.

The screenshot of the crash is attached, which has already used the correct "release" directory CEF binaries.

DynamicCreateTChromium.png

My way of creating Tchromium is different from PopupBrowser. The PopupBrowser create a dynamic window in which there is an OSR TChromium. It's placed in the window at design time. My program creates OSR TChromium in the running time.

[salvadordf]

I just updated CEF4Delphi and removed an obsolete parameter in all OSR demos that caused a crash.
I tried all the OSR demos and they work correctly.

Please, check that the TChromium.OnGetViewRect event in your application doesn't have a "Result" parameter.

[tad.chen]

I test the new CEF4Delphi in my dynamic creating TChromium program.

It works now, the crash issue is fixed.

But the TChromium.OnGetViewRect event in my application always doesn't have a "Result" parameter in both crash version and non-crash version.

[salvadordf]

That's estrange...

Perhaps there was an old BPL or DCU file with a different OnGetViewRect declaration and the last CEF4Delphi update overwrote it.

[salvadordf]

Thanks for reporting this issue!

Please, download CEF4Delphi again.

Now there's a default view rect size (800x600) when the app doesn't provide a valid size in TChromium.OnGetViewRect

[tad.chen]

salvadordf,

These issues fixes including this and IME have applied to oldCEF4Delphi? Now many people still use XP.

[salvadordf]

I'm sorry but it's not possible to fix the IME issue in the 2623 branch used by OldCEF4Delphi because CEF3 fixed this issue in the 2883 branch.
https://bitbucket.org/chromiumembedded/ ... rotocol-in

They added several API calls that are not available in the 2623 branch.

The crash creating TChromium dynamically was caused by a recent change in the TChromium.OnGetViewRect event and it doesn't affect OldCEF4Delphi.