DennisTW

Application.MainformOnTaskbar := false; It works. Thanks so much.

Clicking mainform won't bring it in front of SubForm The following behaviour is different from Lazarus. procedure TForm1.BtnShowFormClick(Sender: TObject); begin SubForm := TForm.Create(Owner); SubForm.Show;//this will make SubForm appear in front of the current Form1. //Even if I click on Main Form1, it won't bring Form1 in front of SubForm again. //what should I do to bring Form1 in front of SubForm again? //I already tried bringtofront and sendtoback end;

from the demo, (PyArg_ParseTuple( args, 'Lii',@psort, @i, @j) <> 0) defines a procedure of (handle, i, j : integer). function TThreadSortForm.Module_Swap( pself, args : PPyObject ) : PPyObject; cdecl; var psort: NativeInt; i, j: Integer; begin with GetPythonEngine do begin if (PyErr_Occurred() = nil) and {$IFDEF CPU64BITS} (PyArg_ParseTuple( args, 'Lii',@psort, @i, @j) <> 0) {$ELSE} (PyArg_ParseTuple( args, 'iii',@psort, @i, @j) <> 0) {$ENDIF} then begin TSortThread(psort).VisualSwap(i,j); Result := ReturnNone; end else Result := nil; end; end; How do I define a function (TheKey, TheValue : String) : String; I cannot find the definitions of the second parameter of PyArg_ParseTuple .

Excuse me. What is DEB? I googled but can't find it.

Thanks for your advice.

After debugging, I traced the problem to the Py_Finalize inside the procedure TPythonEngine.Finalize. Calling Py_Finalize will freeze the program. And Py_Finalize := Import('Py_Finalize'); so, the problem is within the dll. If I skip calling Py_Finalize, there will be a small memory leak of 89 - 104 bytes of Unknown x 1

Have you found the solution? I seem to have found the solution. I created the pythonengine and pythonmodule etc in a background thread procedure TQuoteThread._CreatePython(TheNil: TObject); begin RichEdit1 := TMemo.Create(nil); PythonGUIInputOutput := TPythonGUIInputOutput.Create(nil); PythonGUIInputOutput.UnicodeIO := true; PythonGUIInputOutput.Output := RichEdit1; modDBFireDac := TPythonModule.Create(nil); modDBFireDac.OnInitialization := modDBFireDacInitialization; modDBFireDac.ModuleName := 'DBFireDac'; PyDelphiWrapper := TPyDelphiWrapper.Create(nil); PythonEngine := TPythonEngine.Create(nil); // 4.17 PythonEngine.IO := PythonGUIInputOutput; modDBFireDac.Engine := PythonEngine; PyDelphiWrapper.Engine := PythonEngine; PythonEngine.LoadDll; pyObj := PyDelphiWrapper.Wrap(self); // 4.15 with GetPythonEngine do begin // Define a new variable "T" in the DB module //4.37 modDBFireDac.SetVar('MainForm', pyObj); modDBFireDac.SetVar('BackgroundThread', pyObj); //4.37 Py_XDecRef(pyObj); // Excecute the script ExecStrings(aLines); end; end; Then in the python script, it assigned the delphi thread to a python object delphithread = DBFireDac.BackgroundThread When I need to pass output to Delphi, from within python script, I simply call the delphi thread method delphithread.AddLine(text) In Delphi, the Delphi Thread method use TThread.ForceQueue to call a Form Method which add the output text to a TStringList procedure TQuoteThread.AddLine(TheLine: String); var aObj: TStringObj; begin if (TheLine <> '') and Assigned(UIEvent_PrintLine) then begin TThread.ForceQueue(nil, procedure begin aObj := TStringObj.CreateWith(TheLine); UIEvent_PrintLine(aObj); FreeAndNil(aObj); end, 1); end; end;

I seem to have successfully created PythonEngine inside a thread: RichEdit1 := TMemo.Create(nil); PythonGUIInputOutput := TPythonGUIInputOutput.Create(nil); PythonGUIInputOutput.UnicodeIO := true; PythonGUIInputOutput.Output := RichEdit1; modDBFireDac := TPythonModule.Create(nil); modDBFireDac.OnInitialization := modDBFireDacInitialization; modDBFireDac.ModuleName := 'DBFireDac'; PyDelphiWrapper := TPyDelphiWrapper.Create(nil); PythonEngine := TPythonEngine.Create(nil); // 4.17 PythonEngine.IO := PythonGUIInputOutput; modDBFireDac.Engine := PythonEngine; PyDelphiWrapper.Engine := PythonEngine; PythonEngine.LoadDll; However, when I tried to unload and free the pythonengine inside the same background thread later, it hanged at PythonEngine.Free: FreeAndNil(PyDelphiWrapper); FreeAndNil(modDBFireDac); FreeAndNil(PythonGUIInputOutput); FreeAndNil(RichEdit1); if PythonEngine <> nil then begin PythonEngine.UnloadDll; PythonEngine.Free;// program hanged here!!!! PythonEngine := nil; end; If I don't PythonEngine.Free, Delphi will report memory leak. What should I do?

Thanks. It works now.

Tried. There is no method named " PythonEngine1.Load", but I found PythonEngine1.LoadDll and it worked. Thanks.

Since I need to run Python4Delphi in a separate thread. I first try to modify demo01 of Python4Delphi to create TPythonEngine and TPythonGUIInputOutput at run time instead of design time. procedure TForm1.FormCreate(Sender: TObject); begin PythonGUIInputOutput1:= TPythonGUIInputOutput.Create(self); PythonGUIInputOutput1.Name := 'PythonGUIInputOutput1'; PythonGUIInputOutput1.Output := Memo2; PythonEngine1 := TPythonEngine.Create(self); PythonEngine1.Name := 'PythonEngine1'; PythonEngine1.IO := PythonGUIInputOutput1; end; However, when I run the demo01.exe now, it pops up the error "Python is not properly initialized"!!! How do fix it? My eventual goal is to create TPythonEngine , TPythonGUIInputOutput and other python4delphi components in a separate thread at run time, so as to make python run in its own thread. Please kindly help.

Python4Delphi demo33 (the multi-thread example) (https://blogs.embarcadero.com/learn-how-to-stop-a-thread-inside-python-in-a-delphi-windows-app/) is not working under Delphi 11.1 and Python 3.10.5 (64-bit). When debugged, the function TThreadSortForm.SortModule_GetValue( pself, args : PPyObject ) : PPyObject; cdecl; throws the exception : "OverflowError: Python int too large to convert to C long". I don't understand why as the values of arrays are very small ( below 170). Please help. I need to call Python in multithread.