mainwindow_controller.py

from PyQt5 import QtWidgets as Qt
from controllers.group_edit_controller import GroupEdit
from controllers.groups_overview_controller import GroupsOverview
from model.qtmodels.group_table_model import GroupTableModel
from model.qtmodels.person_table_model import PersonTableModel
from windows import mainwindow
from globals import Global


class MainWindow(Qt.QMainWindow, mainwindow.Ui_MainWindow):

    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setupUi(self)
        self.btnBack.clicked.connect(self.goBack)
        self.goToGroupsOverview()
        self._last_changed = 0

    # all controllers have to call this when they change data in db
    # it prompts every controller before current widget in stack to reload data
    def dataChanged(self):
        self._last_changed = self.stackedWidget.currentIndex()

    def goToGroupsOverview(self):
        groups_overview = GroupsOverview(self)
        self.stackedWidget.addWidget(groups_overview)
        self.stackedWidget.setCurrentWidget(groups_overview)

    # if group_id unfilled - create new group
    def goToGroupEdit(self, group=GroupEdit.NEW_GROUP):
        if group == GroupEdit.NEW_GROUP:
            self._last_changed = self.stackedWidget.currentIndex() + 1
        group_edit = GroupEdit(self, group)
        self.stackedWidget.addWidget(group_edit)
        self.stackedWidget.setCurrentWidget(group_edit)

    def goBack(self):
        current_index = self.stackedWidget.currentIndex()
        if current_index <= 0:
            # we're on groups overview (do nothing)
            return
        if current_index <= self._last_changed:
            self.stackedWidget.widget(current_index - 1).reloadData()
            self._last_changed -= 1
        self.stackedWidget.removeWidget(self.stackedWidget.currentWidget())
        self.stackedWidget.setCurrentIndex(current_index - 1)