How to switch between tabs via pushbutton ? using pyqt - python-3.x

Question

I am newbie and maybe this is silly question.
I want to activate tab by clicking on pushButton . If I click pushButton_1 then it shows/activates tab_1, on the clicking pushButton_2 switches to tab_2, and so on . Bellow there is pic how I tried it but without success. Help me solve this and write correct code down. Thank you in advance.
This is my code :
from spex import *
import sys
class speX (Ui_MainWindow):
def __init__(self, window):
self.setupUi(window)
self.systemButton.clicked.setCurrentIndex(self, 0)
self.cpuButton.clicked.setCurrentIndex(self, 1)
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = speX (MainWindow)
MainWindow.show()
app.exec_()
I want this - when I click systemButton, activate tab indexed as 0, when click cpuButton activate tab indexed as 1.
Error provided there -
Traceback (most recent call last):
File "d:\spex\main.py", line 17, in <module>
ui = speX (MainWindow)
File "d:\spex\main.py", line 9, in __init__
self.systemButton.clicked.setCurrentIndex(self, 0)
AttributeError: 'PyQt5.QtCore.pyqtBoundSignal' object has no attribute 'setCurrentIndex'
This is example of my project - pyuic5 ui to py code
# -*- coding: utf-8 -*-
# Form implementation generated from reading ui file 'D:/spex/example.ui'
#
# Created by: PyQt5 UI code generator 5.13.2
#
# WARNING! All changes made in this file will be lost!
from PyQt5 import QtCore, QtGui, QtWidgets
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(763, 611)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.stackedWidget = QtWidgets.QStackedWidget(self.centralwidget)
self.stackedWidget.setGeometry(QtCore.QRect(270, 70, 361, 361))
self.stackedWidget.setObjectName("stackedWidget")
self.page = QtWidgets.QWidget()
self.page.setObjectName("page")
self.buttonBox = QtWidgets.QDialogButtonBox(self.page)
self.buttonBox.setGeometry(QtCore.QRect(50, 310, 193, 28))
self.buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Cancel|QtWidgets.QDialogButtonBox.Ok)
self.buttonBox.setObjectName("buttonBox")
self.stackedWidget.addWidget(self.page)
self.page_2 = QtWidgets.QWidget()
self.page_2.setObjectName("page_2")
self.commandLinkButton = QtWidgets.QCommandLinkButton(self.page_2)
self.commandLinkButton.setGeometry(QtCore.QRect(70, 190, 222, 48))
self.commandLinkButton.setObjectName("commandLinkButton")
self.stackedWidget.addWidget(self.page_2)
self.pushButton = QtWidgets.QPushButton(self.centralwidget)
self.pushButton.setGeometry(QtCore.QRect(50, 110, 93, 28))
self.pushButton.setObjectName("pushButton")
self.pushButton_2 = QtWidgets.QPushButton(self.centralwidget)
self.pushButton_2.setGeometry(QtCore.QRect(50, 190, 93, 28))
self.pushButton_2.setObjectName("pushButton_2")
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 763, 26))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
self.stackedWidget.setCurrentIndex(0)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.commandLinkButton.setText(_translate("MainWindow", "CommandLinkButton"))
self.pushButton.setText(_translate("MainWindow", "PushButton"))
self.pushButton_2.setText(_translate("MainWindow", "PushButton"))
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)
MainWindow.show()
sys.exit(app.exec_())

Answer 1

In Qt, a signal is emitted when a particular event occurs: a button is clicked, some text is changed, etc.
Signals are then connected to slots, which are functions that can react in some way to those signals. For example, you can create a slot that changes the text in a label, and connect it to a clicked signal of a button: then, when you click on that button, the text is changed.
Why your code does not work?
Well, for instance, setCurrentIndex is a method of a QStackedWidget (similarly to a QTabWidget), so the following doesn't make much sense:
self.systemButton.clicked.setCurrentIndex(self, 0)
Where is the reference to the stacked widget?
In PyQt, you can connect signals and slots like this:
someObject.signal.connect(someFunction)
Note that someFunction is a reference to that function; the following will not work:
someObject.signal.connect(someFunction())
If you want to change the index of a stacked widget after clicking on a button, you have to create a function that changes that index, and connect it to the clicked signal.
class speX (Ui_MainWindow):
def __init__(self, window):
self.setupUi(window)
self.pushButton.clicked.connect(self.goToSecondPage)
def goToSecondPage(self):
self.stackedWidget.setCurrentIndex(1)
I strongly suggest you to carefully study how python classes work and, generally speaking, the Object Oriented programming paradigm.

Answer 2

The simplist solution would be to connect your buttons to a function that changes the tab index on click
tabs = QtWidget.QTabWidget()
tab1 = QtWidget.QWidget()
tabs.addTab(self.tab1, "Tab 1")
systemButton.clicked.connect(tabIndex0)
def tabIndex0():
tabs.setCurrentIndex(0)