QComboBox doesn't display selection as long as it has not lost the focus

[Meaulnes]

I am developing a PyQt5 application. It works properly on Linux platform but I meet an issue when running it on a Windows 10 platform. The trouble is with QComboBox. When the user selects an item in a QComboBox it is not displayed as long as the QComboBox has not lost focus. This means that the previously selected item text stays visible and the user has to click elsewhere in the windows to make the text of the newly selected item appear in the combo. Moreover, when hovering an item in the dropdown list of the combo, its text disappears (whitening of the selected line) Can somebody help me fixing this 2 issues ?

[deanhystad]

This is not normal behavior in windows. Can you post a little example?

[Meaulnes]

Thank you for your answer.
My application has a main window that, in its __init__(), instantiates sub-dialogs. The trouble with the QComboBox doesn' exist in the subdialogs. The combo are working properly. The trouble occurs only in the main window.
Here below is the main.py then the MainWindows's __init__().

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from PyQt5 import QtCore from PyQt5.QtWidgets import QApplication import sys from view.MainWindow import MainWindow        if __name__=='__main__':     current_exit_code=-12345678     app=QApplication(sys.argv)     mainWindow=None     while current_exit_code == -12345678 :         translator = QtCore.QTranslator()         app.installTranslator(translator)         if mainWindow:             mainWindow.close()         #restart from beginning         mainWindow = MainWindow(translator)         MainWindow.show(mainWindow)         current_exit_code=app.exec_()         print('exit code is '+str(current_exit_code))

and an extract of the MainWindow's initialiszation

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class MainWindow(QMainWindow,MainWindowUI.Ui_MainWindow):     '''     classdocs     '''     EXIT_CODE_REBOOT = -12345678   ###################################################################################################################################         def __init__(self, translator,parent=None):         super(MainWindow,self).__init__(parent)         self.setupUi(self)         self.translator=translator         self.calculator=None                   'THIS IS FOR PYINSTALLER ONLY'         'Folder structure is quite different when running in a bundle'         'Please see pyinstaller’s documentation'         self.frozen = 'not'         if getattr(sys, 'frozen', False): #return False if the attribute is not found             self.frozen = 'yes'             self.bundle_dir = sys._MEIPASS             self.model = Model(self.bundle_dir)#we pass the path to database             'the path to the translated .qm files'             self.trad_path=os.path.join(self.bundle_dir ,'translate')              else:             self.frozen='not'             'l’import export is reserved to the frozen application (bundled)'             self.actionImport_Export_Databases.setVisible(False)             self.model = Model()             'the path to the .qm translated files'             (filepath,filename)=os.path.split(__file__)             self.trad_path=os.path.join(filepath,'..','translate')                             self.controller = Controller(self.model)         self.unitSetter=UnitSetter(self.model,self)         self.language_setter=LanguageSetter(self.model,self)         if not self.model.language:             self.language_setter.setModal(True)             self.language_setter.show()          else: self.set_language(self.model.language[1])         #IMPORTANT:         #setting of locale is deported in showEvent as language is not ready at this stage of init'                   #colors must be set before all dialogs         'due to the translation into util.init_hop_usage_dic , util should be created after setting the language'         self.util=Utils(self.model)               self.util.init_hop_usage_dic()         self.util.init_yeast_form_dic()         self.style_key_list=self.model.style_list         self.set_active_colors()         self.create_constant_list()         self.constant_setter=ConstantDialog(self.model,self.util,self.constant_list)         self.maltDialog=MaltDialog(self.model,self.controller,self.util)         self.malt_chooser=MaltChooser(self.model,self.controller,self.util,self)         self.sugarDialog=SugarDialog(self.model,self.controller,self.util)         self.hopDialog=HopDialog(self.model,self.controller,self.util)         self.restDialog=RestDialog(self.model,self.controller, self.util)         self.yeastDialog=YeastDialog(self.model,self.controller,self.util)         self.recipeDialog = RecipeDialog(self.model,self.controller,self.util)         self.colorDialog = ColorDialog(self.model,self.controller,self.util)         self.ABV_calculator=ABVCalculator(self.model,self.controller, self.util)         self.priming_calculator=PrimingCalculator(self.model,self.controller,self.util)         self.equipmentDialog=EquipmentDialog(self.model,self.controller,self.util)

[Meaulnes]

I eventually found that it was only a styling issue. I mistakenly applied a color identical to the background-color on the selection.