Tukukkk

I have sql query. My push button connects with sql - it takes long time. During it, my GUI is not responding - is it possible to make it responds?

QtCore.QCoreApplication.processEvents() doesnt work.

QApp.py

# -- coding: utf-8 --



from PyQt5 import QtGui, QtWidgets, QtCore

import qdarkstyle

import pyodbc



class MainWindow(QtWidgets.QMainWindow):

    def __init__(self, parent=None):

        super(MainWindow,self).__init__(parent)



        self.main_frame()

        self.center() #center frame

        self.layout_init() #widgets layout



    def main_frame(self):

        ### actions on meenubar

        exitAct = QtWidgets.QAction('&Exit', self)

        exitAct.setShortcut('Ctrl+Q')

        exitAct.setStatusTip('Exit application')

        exitAct.triggered.connect(self.close)

        self.statusBar()



        moreinfo = QtWidgets.QAction('&Help',self)

        moreinfo.setStatusTip('More information')

        moreinfo.triggered.connect(self.information)

        self.statusBar()



        ### menubar

        menubar = self.menuBar()

        fileMenu = menubar.addMenu('&File')

        fileMenu.addAction(exitAct)

        fileMenu = menubar.addMenu('&Help')

        fileMenu.addAction(moreinfo)





        ### basic geometry and color

        self.setWindowTitle('Villain')

        self.setWindowIcon(QtGui.QIcon('dc1.png'))

        self.setStyleSheet((qdarkstyle.load_stylesheet_pyqt5()))





    def layout_init(self):

        self.grid = QtWidgets.QGridLayout()

        central_widget = QtWidgets.QWidget()

        self.setCentralWidget(central_widget)



        ### widgets

        self.tablewidget = QtWidgets.QTableWidget()

        self.tablewidget.setColumnCount(4)

        self.tablewidget.setHorizontalHeaderLabels(["FileNameTransformed", "OrderItemCode", "Imported", "Row"])

        self.tablewidget.horizontalHeader().setDefaultAlignment(QtCore.Qt.AlignLeft | QtCore.Qt.AlignVCenter)

        self.tablewidget.horizontalHeader().setStretchLastSection(True)

        self.tablewidget.resizeColumnsToContents()

        self.tablewidget.setSelectionMode(QtWidgets.QAbstractItemView.SingleSelection)

        self.tablewidget.setEditTriggers(QtWidgets.QAbstractItemView.NoEditTriggers)

        #self.tablewidget.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)



        self.textbox = QtWidgets.QLineEdit()

        self.textbox.setPlaceholderText('IMEI')

        self.textbox.setEnabled(True)

        regexp = QtCore.QRegExp('^(0d+|[1-9][0-9]+)$') #IMEI = only int

        self.textbox.setValidator(QtGui.QRegExpValidator(regexp))



        self.pb = QtWidgets.QPushButton(self.tr("Run process"))

        self.pb.setDisabled(True)

        self.textbox.textChanged.connect(self.disableButton)

        self.pb.clicked.connect(self.on_clicked_pb)





        self.clearbutton = QtWidgets.QPushButton(self.tr("Clear all"))

        self.clearbutton.setDisabled(True)

        self.clearbutton.clicked.connect(self.on_clicked_clear)



        ### make vidgets alive

        self.centralWidget().setLayout(self.grid)

        self.grid.addWidget(self.textbox)

        self.grid.addWidget(self.tablewidget)

        self.grid.addWidget(self.pb)

        self.grid.addWidget(self.clearbutton)





    ### center main window

    def center(self):

        qr = self.frameGeometry()

        cp = QtWidgets.QDesktopWidget().availableGeometry().center()

        qr.moveCenter(cp)

        self.move(qr.topLeft())







    def information(self):

        QtWidgets.QMessageBox.information(self,'Information','Version: 1.19.11.18n'

                                                             'This is the prototype of the applicationnn'

                                                             'Please, contact karol.chojnowski@digitalcaregroup.com for comments and suggestionsnn'

                                          'Digital Care - Data Processing Team')



    def disableButton(self):

        if len(self.textbox.text())> 0:

            self.pb.setDisabled(False)

            self.clearbutton.setDisabled(False)

        else:

            self.pb.setDisabled(True)

            self.clearbutton.setDisabled(True)





    ### run process button

    @QtCore.pyqtSlot()

    def on_clicked_pb(self):

        if len(self.textbox.text()) == 0:

            pass

        else:

            self.sql_query()





    ### clear all

    @QtCore.pyqtSlot()

    def on_clicked_clear(self):

        if len(self.textbox.text())> 0:

            self.textbox.clear()

            self.tablewidget.setRowCount(0)

            self.tablewidget.setColumnWidth(3, 200)



    def setCredentials(self, credentials):

        self._credentials = credentials



    def sql_query(self):

        ser = "10.96.6.14"

        base = "PROD_WAREX2"

        username, pwd = self._credentials



        QtCore.QCoreApplication.processEvents()

        try:

            self.connection = pyodbc.connect(driver='{SQL Server}', server=ser, database=base,

                         user=username, password=pwd)

            cursor = self.connection.cursor()

            self.res = cursor.execute(""" SELECT FI.FileNameTransformed,

                FI.OrderItemCode,

                FIR.Imported,

                FR.Row

                FROM [FileRows] AS FR

                JOIN [FileImportRows] AS FIR ON FR.RowId = FIR.RowId

                JOIN [FileImports] AS FI ON FIR.FileImportId = FI.Id 

                WHERE FR.Row LIKE ? """, ('%' + self.textbox.text() + '%'))

            if not cursor.rowcount:

                QtWidgets.QMessageBox.information(self, 'IMEI', "No items found")

                cursor.close()

                pass

            else:

                self.tablewidget.setRowCount(0)

                for row, form in enumerate(self.res):

                    self.tablewidget.insertRow(row)

                    for column, item in enumerate(form):

                        newitem = QtWidgets.QTableWidgetItem(str(item))

                        self.tablewidget.setItem(row, column, newitem)

                cursor.close()

                self.table_performance()

                self.tablewidget.sortItems(0, order=QtCore.Qt.DescendingOrder)

        except:

            QtWidgets.QMessageBox.warning(self, 'Error', "Something went wrongnn"

                                          "Contact karol.chojnowski@digitalcaregroup.com")

            QtWidgets.QMessageBox.setStyleSheet((qdarkstyle.load_stylesheet_pyqt5()))





    def table_performance(self):

        self.tablewidget.resizeColumnsToContents()

        self.tablewidget.setColumnWidth(3, 2500)

        self.tablewidget.setHorizontalScrollMode(QtWidgets.QAbstractItemView.ScrollPerPixel)

main .py:

Villain.py

# -- coding: utf-8 --



import sys

from PyQt5 import QtWidgets,QtGui

from QLogin import LoginDialog

from QApp import MainWindow

import os





def resource_path(relative_path):

if hasattr(sys, '_MEIPASS'):

    return os.path.join(sys._MEIPASS, relative_path)

return os.path.join(os.path.abspath("."), relative_path)





if __name__ == '__main__':



app = QtWidgets.QApplication(sys.argv)



login = LoginDialog()

login.setWindowIcon(QtGui.QIcon(resource_path('dc1.png')))



if login.exec_() != QtWidgets.QDialog.Accepted:

    sys.exit(-1)



window = MainWindow()

window.setWindowIcon(QtGui.QIcon(resource_path('dc1.png')))

window.setGeometry(500, 150, 800, 500)

window.setCredentials(login.credentials()) # <----

window.show()

sys.exit(app.exec_())

The use of processEvents() implies in most cases a bad design. If you have a heavy task, do not execute it in the main thread, execute it in another thread and send the necessary data to the main thread by means of signals or with QMetaObject::invokeMethod() (this last option will be used since it is not necessary so much connection).

On the other hand you should only add the stylesheet once, if there are new widgets they will take as a basis the stylesheet.

# -- coding: utf-8 --

import threading

from PyQt5 import QtGui, QtWidgets, QtCore

import qdarkstyle

import pyodbc



class MainWindow(QtWidgets.QMainWindow):

    def __init__(self, parent=None):

        super(MainWindow,self).__init__(parent)



        self.main_frame()

        self.center() #center frame

        self.layout_init() #widgets layout



    def main_frame(self):

        ### actions on meenubar

        exitAct = QtWidgets.QAction('&Exit', self, shortcut='Ctrl+Q', statusTip='application')

        exitAct.triggered.connect(self.close)



        moreinfo = QtWidgets.QAction('&Help',self, statusTip='More information')

        moreinfo.triggered.connect(self.information)



        ### menubar

        menubar = self.menuBar()

        fileMenu = menubar.addMenu('&File')

        fileMenu.addAction(exitAct)

        fileMenu = menubar.addMenu('&Help')

        fileMenu.addAction(moreinfo)



        ### basic geometry and color

        self.setWindowTitle('Villain')

        self.setWindowIcon(QtGui.QIcon('dc1.png'))

        self.setStyleSheet((qdarkstyle.load_stylesheet_pyqt5()))



    def layout_init(self):

        central_widget = QtWidgets.QWidget()

        self.setCentralWidget(central_widget)



        ### widgets

        self.tablewidget = QtWidgets.QTableWidget()

        self.tablewidget.setColumnCount(4)

        self.tablewidget.setHorizontalHeaderLabels(["FileNameTransformed", "OrderItemCode", "Imported", "Row"])

        self.tablewidget.horizontalHeader().setDefaultAlignment(QtCore.Qt.AlignLeft | QtCore.Qt.AlignVCenter)

        self.tablewidget.horizontalHeader().setStretchLastSection(True)

        self.tablewidget.resizeColumnsToContents()

        self.tablewidget.setSelectionMode(QtWidgets.QAbstractItemView.SingleSelection)

        self.tablewidget.setEditTriggers(QtWidgets.QAbstractItemView.NoEditTriggers)

        #self.tablewidget.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)



        self.textbox = QtWidgets.QLineEdit()

        self.textbox.setPlaceholderText('IMEI')

        self.textbox.setEnabled(True)

        regexp = QtCore.QRegExp('^(0d+|[1-9][0-9]+)$') #IMEI = only int

        self.textbox.setValidator(QtGui.QRegExpValidator(regexp))



        self.pb = QtWidgets.QPushButton(self.tr("Run process"))

        self.pb.setDisabled(True)

        self.textbox.textChanged.connect(self.disableButton)

        self.pb.clicked.connect(self.on_clicked_pb)



        self.clearbutton = QtWidgets.QPushButton(self.tr("Clear all"))

        self.clearbutton.setDisabled(True)

        self.clearbutton.clicked.connect(self.on_clicked_clear)



        ### make vidgets alive

        grid = QtWidgets.QGridLayout(central_widget)

        grid.addWidget(self.textbox)

        grid.addWidget(self.tablewidget)

        grid.addWidget(self.pb)

        grid.addWidget(self.clearbutton)



        self.table_performance()



    ### center main window

    def center(self):

        qr = self.frameGeometry()

        cp = QtWidgets.QDesktopWidget().availableGeometry().center()

        qr.moveCenter(cp)

        self.move(qr.topLeft())



    def information(self):

        QtWidgets.QMessageBox.information(self,'Information','Version: 1.19.11.18n'

                                                             'This is the prototype of the applicationnn'

                                                             'Please, contact karol.chojnowski@digitalcaregroup.com for comments and suggestionsnn'

                                          'Digital Care - Data Processing Team')





    @QtCore.pyqtSlot()

    def disableButton(self):

        val = bool(self.textbox.text())

        self.pb.setDisabled(not val)

        self.clearbutton.setDisabled(not val)



    ### run process button

    @QtCore.pyqtSlot()

    def on_clicked_pb(self):

        if self.textbox.text():

            threading.Thread(target=self.sql_query, daemon=True).start()

    ### clear all

    @QtCore.pyqtSlot()

    def on_clicked_clear(self):

        if self.textbox.text():

            self.textbox.clear()

            self.tablewidget.setRowCount(0)

            self.tablewidget.setColumnWidth(3, 200)



    def setCredentials(self, credentials):

        self._credentials = credentials



    def table_performance(self):

        self.tablewidget.resizeColumnsToContents()

        self.tablewidget.setColumnWidth(3, 2500)

        self.tablewidget.setHorizontalScrollMode(QtWidgets.QAbstractItemView.ScrollPerPixel)



    @QtCore.pyqtSlot(str, str)

    def show_warning(self, title, msg):

        QtWidgets.QMessageBox.information(self, title, msg)



    @QtCore.pyqtSlot()

    def clear_items(self):

        self.tablewidget.setRowCount(0)



    @QtCore.pyqtSlot(int, int, str)

    def add_item(self, row, column, val):

        if row >= self.tablewidget.rowCount():

            self.tablewidget.insertRow(self.tablewidget.rowCount())

        newitem = QtWidgets.QTableWidgetItem(val)

        self.tablewidget.setItem(row, column, newitem)



    @QtCore.pyqtSlot()

    def sort_items(self):

        self.tablewidget.sortItems(0, order=QtCore.Qt.DescendingOrder)



    def sql_query(self):

        ser = "10.96.6.14"

        base = "PROD_WAREX2"

        username, pwd = self._credentials

        try:

            connection = pyodbc.connect(driver='{SQL Server}', server=ser, database=base,

                         user=username, password=pwd)

            cursor = connection.cursor()

            res = cursor.execute(""" SELECT FI.FileNameTransformed,

                FI.OrderItemCode,

                FIR.Imported,

                FR.Row

                FROM [FileRows] AS FR

                JOIN [FileImportRows] AS FIR ON FR.RowId = FIR.RowId

                JOIN [FileImports] AS FI ON FIR.FileImportId = FI.Id 

                WHERE FR.Row LIKE ? """, ('%' + self.textbox.text() + '%'))

            if not cursor.rowcount:

                QtCore.QMetaObject.invokeMethod(self, "show_warning", 

                    QtCore.Qt.QueuedConnection, 

                    QtCore.Q_ARG(str, 'IMEI'), QtCore.Q_ARG(str, "No items found"))

            else:

                QtCore.QMetaObject.invokeMethod(self, "clear_items", QtCore.Qt.QueuedConnection)

                QtCore.QThread.msleep(10)

                for row, form in enumerate(res):

                    for column, item in enumerate(form):

                        QtCore.QMetaObject.invokeMethod(self, "add_item", 

                            QtCore.Qt.QueuedConnection,

                            QtCore.Q_ARG(int, row), QtCore.Q_ARG(int, column), QtCore.Q_ARG(str, str(item)))

                        QtCore.QThread.msleep(10)

                QtCore.QMetaObject.invokeMethod(self, "sort_items", QtCore.Qt.QueuedConnection)

            cursor.close()

        except:

            QtCore.QMetaObject.invokeMethod(self, "show_warning", 

                    QtCore.Qt.QueuedConnection, 

                    QtCore.Q_ARG(str, 'Error'), QtCore.Q_ARG(str, "Something went wrongnn"

                                          "Contact karol.chojnowski@digitalcaregroup.com"))