webgui: enable usage of CEF in canvas painter

gui/canvaspainter/v7/src/TCanvasPainter.cxx

@@ -34,6 +34,30 @@
 #include "TClass.h"
 #include "TBufferJSON.h"
 
+#ifdef WEBGUI_WITH_CEF
+#include "../cef/simple_app.h"
+#include "TApplication.h"
+#include "TTimer.h"
+
+class TCefTimer : public TTimer {
+public:
+   TCefTimer(Long_t milliSec, Bool_t mode) : TTimer(milliSec, mode)
+   {
+      // construtor
+   }
+   virtual ~TCefTimer()
+   {
+      // destructor
+   }
+   virtual void Timeout()
+   {
+      // just dummy workaround
+      CefDoMessageLoopWork();
+   }
+};
+
+#endif
+
 namespace {
 
 /** \class TCanvasPainter
@@ -162,6 +186,76 @@ void TCanvasPainter::PopupBrowser()
 
    addr.Form("%s/web7gui/%s/draw.htm?webcanvas", fAddr.c_str(), GetName());
 
+
+#ifdef WEBGUI_WITH_CEF
+     const char* cef = gSystem->Getenv("CEF_PATH");
+     Info("Show", "CEF %s", cef);
+     if (cef && !gSystem->AccessPathName(cef)) {
+
+        TApplication* root_app = gROOT->GetApplication();
+
+        printf("Start cef window with addr %s app %p\n", addr.Data(), root_app);
+
+        CefMainArgs main_args(root_app->Argc(), root_app->Argv());
+
+        // CEF applications have multiple sub-processes (render, plugin, GPU, etc)
+        // that share the same executable. This function checks the command-line and,
+        // if this is a sub-process, executes the appropriate logic.
+
+/*         int exit_code = CefExecuteProcess(main_args, NULL, NULL);
+        if (exit_code >= 0) {
+          // The sub-process has completed so return here.
+          return exit_code;
+        }
+*/
+
+        // Install xlib error handlers so that the application won't be terminated
+        // on non-fatal errors.
+//         XSetErrorHandler(XErrorHandlerImpl);
+//         XSetIOErrorHandler(XIOErrorHandlerImpl);
+
+        // Specify CEF global settings here.
+        CefSettings settings;
+
+      //  settings.multi_threaded_message_loop = false; // not supported
+      //  settings.external_message_pump = false;
+        const char* rootsys = gSystem->Getenv("ROOTSYS");
+
+        printf("Get build dir %s\n", rootsys);
+
+        TString path, path2, cef_main;
+        path.Form("%s/Resources/", cef);
+        path2.Form("%s/Resources/locales/", cef);
+        cef_main.Form("%s/bin/cef_main", rootsys);
+
+         cef_string_ascii_to_utf16(path.Data(), path.Length(), &settings.resources_dir_path);
+
+         cef_string_ascii_to_utf16(path2.Data(), path2.Length(), &settings.locales_dir_path);
+
+         settings.no_sandbox = true;
+         // settings.single_process = true;
+
+
+        // SimpleApp implements application-level callbacks for the browser process.
+        // It will create the first browser instance in OnContextInitialized() after
+        // CEF has initialized.
+        CefRefPtr<SimpleApp> *app = new CefRefPtr<SimpleApp>(new SimpleApp(addr.Data(), cef_main.Data()));
+
+        // Initialize CEF for the browser process.
+        CefInitialize(main_args, settings, app->get(), NULL);
+
+        // let run CEF message loop, should be improved later
+        TCefTimer *timer = new TCefTimer(10, kTRUE);
+        timer->TurnOn();
+
+        // Shut down CEF.
+        //CefShutdown();
+
+        return;
+     }
+#endif
+
+
    if (gSystem->InheritsFrom("TMacOSXSystem"))
       exec.Form("open %s", addr.Data());
    else