import sys

from PyQt5 import QtCore, uic, QtWidgets
from PyQt5.QtCore import Qt

qt_creator_file = "mainwindow.ui"
Ui_MainWindow, QtBaseClass = uic.loadUiType(qt_creator_file)


class TodoModel(QtCore.QAbstractListModel):
    def __init__(self, *args, todos=None, **kwargs):
        super(TodoModel, self).__init__(*args, **kwargs)
        self.todos = todos or []

    def data(self, index, role):
        if role == Qt.DisplayRole:
            status, text = self.todos[index.row()]
            return text

    def rowCount(self, index):
        return len(self.todos)


class MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        Ui_MainWindow.__init__(self)
        self.setupUi(self)
        self.module = TodoModel(todos=[(False, '我的第一个 Todo 项目')])
        self.todoView.setModel(self.module)

        self.addButton.pressed.connect(self.add)
        self.deleteButton.pressed.connect(self.delete)

    def add(self):
        """
        Add an item to our todo list, getting the text from the QLineEdit.todoEdit
        and then clearing it.
        :return:
        """
        text = self.todoEdit.text()
        if text:
            self.module.todos.append((False, text))
            self.todoEdit.setText("")
            self.module.layoutChanged.emit()

    def delete(self):
        indexes = self.todoView.selectedIndexes()
        if indexes:
            index = indexes[0]
            del self.module.todos[index.row()]
            self.todoView.clearSelection()
            self.module.layoutChanged.emit()


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    window = MainWindow()
    window.show()
    app.exec_()