Tag: complex

TLDR: Is my code following best practices for OOP and PyQt5 regarding inheritance, and is it okay to initialise classes within another class? What can I do to improve my methods, or what would be a better approach to my specific problem?

I’m very new to OOP and PyQt5. My Code creates a GUI with 2 tab widgets, each with multiple tabs, and each tab with its own layouts and widgets.

To make the code manageable (in my beginner opinion), I’ve turned everything into a class. The Window class handles the Window and Layout and creates instances of the tab widgets. The Tabs classes handle Tab layouts and create instances of tablets (pages). The Tablet class handles tablets and their layouts and adds widgets such as buttons, labels etc.

Window Layout

Versions:

python                 3.7.3
PyQt5                  5.15.4
PyQt5-Qt5              5.15.2
PyQt5-sip              12.8.1

CODE

"""
Initialises Window, Sets out the geometry management, and adds Widgets
"""
import sys

from PyQt5.QtCore import pyqtSignal, pyqtSlot
from PyQt5.QtWidgets import (
  QApplication, QGridLayout, QMainWindow, QTableWidgetItem, QWidget
)

from PyQt5.QtWidgets import (
  QComboBox, QFormLayout, QHBoxLayout, QVBoxLayout,
  QLabel, QPushButton, QTabWidget, QTableWidget, QWidget
)


class Window(QMainWindow):
    """Create an instance of Window. Sets up main Window"""
    # my_signal = pyqtSignal(int)
    def __init__(self):
        super().__init__()
        self.setMinimumSize(1000, 800)
        self.centralWgt = QWidget()  # create central widget
        self.setCentralWidget(self.centralWgt)  # set central widget
        self.tabIn = InputTab()  # create input tab widget
        self.tabOut = OutputTab()  # create input tab widget
        self.windowLayout()  # set window layout

        # TODO: Move this and "test" to a class to keep Window minimal
        self.tabIn.tablet1.btnApply.clicked.connect(self.test)

    def test(self):
        """
        When tabIn tablet1 btnApply pressed, Do something in tabOut tablet1
        """
        self.tabOut.tablet1.textGreeting.setText(“Hello”)
        print("Here!")

    def windowLayout(self):
        """Handles the main windows layout"""
        self.layout = QGridLayout()
        self.centralWgt.setLayout(self.layout)
        self.layout.addWidget(self.tabIn, 0, 1)  # Add widgets to layout
        self.layout.addWidget(self.tabOut, 1, 1, 2, 1)  # Add widgets to layout
        # Handle window and widget resizing
        self.layout.setColumnStretch(0, 1)
        self.layout.setColumnStretch(1, 1)
        self.layout.setRowStretch(0, 1)
        self.layout.setRowStretch(1, 1)
        self.layout.setRowStretch(2, 1)


# TAB MANAGEMENT


class Tabs(QTabWidget):
    """Tabs master class"""
    def __init__(self):
        super().__init__()
        self.tabs = QTabWidget()  # Initialise Tab Widget
        self.layout = QVBoxLayout()  # Define Tab Widget Layout
        self.setLayout(self.layout)  # Set Tab Widget Layout
        self.setStyleSheet('QTabBar { font-size: 12pt;}')  # Set tab title size


class InputTab(Tabs):
    """Creates and sets up the InputTab Class. Inherits from Tab Class"""
    def __init__(self):
        super().__init__()
        self.tablet1 = ItemTablet(QWidget())  # Initialise tablet
        self.tabs.addTab(self.tablet1, "Item Queries")  # Add tablet
        self.layout.addWidget(self.tabs)  # Add tablets to layout


class OutputTab(Tabs):
    """Creates and sets up the OutputTab Class. Inherits from Tab Class"""
    def __init__(self):
        super().__init__()
        self.tablet1 = TableTablet(QWidget())  # Initialise tablet
        self.tabs.addTab(self.tablet1, "Output - Item Table")  # Add tablet
        self.layout.addWidget(self.tabs)  # Add tablets to layout


# TABLET MANAGEMENT #


class Tablets(QTableWidget):
    """The Tablets master class. Contains shared methods, variables"""
    def __init__(self, widget):
        super().__init__()
        self.widget = widget  # set tablet widget as given widget type
        self.layout = QVBoxLayout()  # create tablet outer layout
        self.setLayout(self.layout)  # set tablet outer layout
        self.setStyleSheet('font-size: 10pt;')  # Set tablet font size

    def populateForm(self, formFields):
        """Populates a form layout with dict key value pairs"""
        for k, v in formFields.items():
            self.frmLayout.addRow(k, v)  # Add items to tablet form layout

    def stdButtons(self):
        """Adds Apply and Clear buttons to bottom of tablet."""
        self.btnApply = QPushButton(text="Apply")
        self.btnClear = QPushButton(text="Clear")
        self.btnLayout.addWidget(self.btnApply)
        self.btnLayout.addWidget(self.btnClear)

    def stdFormLayout(self):
        """Creates a Form with horizontal buttons at bottom"""
        self.frmLayout = QFormLayout()  # create tablet sublayout
        self.btnLayout = QHBoxLayout()  # create tablet sublayout
        self.layout.addLayout(self.frmLayout)  # set tablet sublayout
        self.layout.addLayout(self.btnLayout)  # set tablet sublayout


class ItemTablet(Tablets):
    """Handles Item Tablet"""
    def __init__(self, widget):
        super().__init__(widget)
        self.stdFormLayout()  # choose stdFormLayout as a sublayout
        self.stdButtons()  # add stdButtons to sublayout
        # create form items
        self.lblItems = QLabel("Item name")
        self.cmbItems = QComboBox()
        self.cmbItems.addItems(("1", "2", "3"))

        # add form items to dict to setup widget associations
        self.formFields = {
            self.lblItems: self.cmbItems,
        }
        self.populateForm(self.formFields)  # add items to form layout


class TableTablet(Tablets, QTableWidget):
    """Handles the output table tablet"""
    def __init__(self, widget):
        super().__init__(widget)
        self.style = "::section{Background-color:lightgray;border-radius:9px;}"
        self.header = self.horizontalHeader()
        self.header.setStyleSheet(self.style)
        self.textGreeting = QLineEdit()
        self.layout.addWidget(self.textGreeting)


if __name__ == "__main__":
    app = QApplication(())
    window = Window()
    window.show()
    sys.exit(app.exec_())