Stackwidget in Pyqt5 python

Question

I'm creating a screen with StackWidget consist of 3 pages. The problem is that only one page of the stackwidget pages showing all widgets inside it but the other pages cutting three element in the corners, see the photos

the error page:

correct page and i want the other pages show all widgets in the four corners:

    from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(1200, 679)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton.setGeometry(QtCore.QRect(30, 100, 93, 28))
        self.pushButton.setObjectName("pushButton")
        self.pushButton_2 = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton_2.setGeometry(QtCore.QRect(30, 220, 93, 28))
        self.pushButton_2.setObjectName("pushButton_2")
        self.pushButton_3 = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton_3.setGeometry(QtCore.QRect(30, 330, 93, 28))
        self.pushButton_3.setObjectName("pushButton_3")
        self.stackedWidget = QtWidgets.QStackedWidget(self.centralwidget)
        self.stackedWidget.setGeometry(QtCore.QRect(170, 0, 1011, 631))
        self.stackedWidget.setObjectName("stackedWidget")
        self.page_3 = QtWidgets.QWidget()
        self.page_3.setObjectName("page_3")
        self.pushButton_4 = QtWidgets.QPushButton(self.page_3)
        self.pushButton_4.setGeometry(QtCore.QRect(10, 10, 93, 28))
        self.pushButton_4.setObjectName("pushButton_4")
        self.pushButton_5 = QtWidgets.QPushButton(self.page_3)
        self.pushButton_5.setGeometry(QtCore.QRect(880, 20, 93, 28))
        self.pushButton_5.setObjectName("pushButton_5")
        self.pushButton_6 = QtWidgets.QPushButton(self.page_3)
        self.pushButton_6.setGeometry(QtCore.QRect(10, 580, 93, 28))
        self.pushButton_6.setObjectName("pushButton_6")
        self.pushButton_7 = QtWidgets.QPushButton(self.page_3)
        self.pushButton_7.setGeometry(QtCore.QRect(890, 590, 93, 28))
        self.pushButton_7.setObjectName("pushButton_7")
        self.stackedWidget.addWidget(self.page_3)
        self.page_4 = QtWidgets.QWidget()
        self.page_4.setObjectName("page_4")
        self.lineEdit = QtWidgets.QLineEdit(self.page_4)
        self.lineEdit.setGeometry(QtCore.QRect(10, 30, 113, 22))
        self.lineEdit.setObjectName("lineEdit")
        self.lineEdit_2 = QtWidgets.QLineEdit(self.page_4)
        self.lineEdit_2.setGeometry(QtCore.QRect(870, 580, 113, 22))
        self.lineEdit_2.setObjectName("lineEdit_2")
        self.lineEdit_3 = QtWidgets.QLineEdit(self.page_4)
        self.lineEdit_3.setGeometry(QtCore.QRect(30, 570, 113, 22))
        self.lineEdit_3.setObjectName("lineEdit_3")
        self.lineEdit_4 = QtWidgets.QLineEdit(self.page_4)
        self.lineEdit_4.setGeometry(QtCore.QRect(860, 30, 113, 22))
        self.lineEdit_4.setObjectName("lineEdit_4")
        self.stackedWidget.addWidget(self.page_4)
        self.page_5 = QtWidgets.QWidget()
        self.page_5.setObjectName("page_5")
        self.calendarWidget = QtWidgets.QCalendarWidget(self.page_5)
        self.calendarWidget.setGeometry(QtCore.QRect(10, 10, 392, 236))
        self.calendarWidget.setObjectName("calendarWidget")
        self.calendarWidget_2 = QtWidgets.QCalendarWidget(self.page_5)
        self.calendarWidget_2.setGeometry(QtCore.QRect(600, 20, 392, 236))
        self.calendarWidget_2.setObjectName("calendarWidget_2")
        self.calendarWidget_3 = QtWidgets.QCalendarWidget(self.page_5)
        self.calendarWidget_3.setGeometry(QtCore.QRect(610, 380, 392, 236))
        self.calendarWidget_3.setObjectName("calendarWidget_3")
        self.calendarWidget_4 = QtWidgets.QCalendarWidget(self.page_5)
        self.calendarWidget_4.setGeometry(QtCore.QRect(10, 380, 392, 236))
        self.calendarWidget_4.setObjectName("calendarWidget_4")
        self.stackedWidget.addWidget(self.page_5)
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 1200, 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(2)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton.setText(_translate("MainWindow", "1"))
        self.pushButton_2.setText(_translate("MainWindow", "2"))
        self.pushButton_3.setText(_translate("MainWindow", "3"))
        self.pushButton_4.setText(_translate("MainWindow", "PushButton"))
        self.pushButton_5.setText(_translate("MainWindow", "PushButton"))
        self.pushButton_6.setText(_translate("MainWindow", "PushButton"))
        self.pushButton_7.setText(_translate("MainWindow", "PushButton"))

Blockquote

import sys
from PyQt5.QtWidgets import QMainWindow, QApplication, QAction ,QFileDialog
from stackwidgettest import *
class MyForm(QMainWindow):
    def __init__(self):
        super().__init__()
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        
        self.ui.pushButton.clicked.connect(self.moveforward)  
        self.ui.pushButton_2.clicked.connect(self.moveback)
        self.ui.pushButton_3.clicked.connect(self.movebacks)
        
        
    def moveforward(self):
        self.ui.page_3.show()
        self.ui.page_4.hide()
        self.ui.page_5.hide()
        
    def moveback(self):
        self.ui.page_3.hide()
        self.ui.page_4.show()
        self.ui.page_5.hide()
    def movebacks(self):
        self.ui.page_3.hide()
        self.ui.page_4.hide()
        self.ui.page_5.show()

if __name__=="__main__":    
    app = QApplication(sys.argv)
    w = MyForm()
    w.show()
    sys.exit(app.exec_())

Answer 1

The problem solved by setCurrentIndex() method for the stackwidget