Python pyqt4 从函数访问 QTextEdit

Question

I'm trying to write a notepad application, so far i have a gui without functionality. Every element of my gui is in separate function, and then is called in init method. For example in create_new_file(self) function I was trying to get text from QTextEdit .toPlainText() method, but how can i access this field from text_edit_area(self) function?

import sys
from PyQt4 import QtGui, QtCore


class Editor(QtGui.QMainWindow):

    def __init__(self):
        super(Editor, self).__init__()
        self.setGeometry(100, 100, 500, 500)
        self.setWindowTitle('Text Editor')
        self.setWindowIcon(QtGui.QIcon('editor.png'))

        self.statusBar()
        self.main_menu()
        self.text_edit_area()
        self.toolbar()

        self.show()


    def main_menu(self):

        # CREATE MAIN MENU
        menu = self.menuBar()

        # MENU ACTIONS
        file_exit_action = QtGui.QAction('&Exit', self)
        file_exit_action.setShortcut('Ctrl+Q')
        file_exit_action.setStatusTip('Close application')
        file_exit_action.triggered.connect(self.close_application)

        file_new_file_action = QtGui.QAction('&New File', self)
        file_new_file_action.setShortcut('Ctrl+N')
        file_new_file_action.setStatusTip('Create a new file')
        file_new_file_action.triggered.connect(self.create_new_file)

        file_open_file_action = QtGui.QAction('&Open File', self)
        file_open_file_action.setShortcut('Ctrl+O')
        file_open_file_action.setStatusTip('Open file')
        file_open_file_action.triggered.connect(self.open_file)

        file_save_file_action = QtGui.QAction('&Save File', self)
        file_save_file_action.setShortcut('Ctrl+S')
        file_save_file_action.setStatusTip('Save opened file')
        file_save_file_action.triggered.connect(self.save_file)

        edit_undo_action = QtGui.QAction('&Undo', self)
        edit_undo_action.triggered.connect(self.undo)

        format_change_font_action = QtGui.QAction('&Change Font', self)
        format_change_font_action.triggered.connect(self.change_font)

        view_maximize_action = QtGui.QAction('&Maximize', self)
        view_maximize_action.triggered.connect(self.maximize)

        help_about_action = QtGui.QAction('&About', self)
        help_about_action.triggered.connect(self.about)


        # FILE MENU
        file_menu = menu.addMenu('&File')
        file_menu.addAction(file_exit_action)
        file_menu.addAction(file_new_file_action)
        file_menu.addAction(file_open_file_action)
        file_menu.addAction(file_save_file_action)


        # EDIT MENU
        edit_menu = menu.addMenu('&Edit')
        edit_menu.addAction(edit_undo_action)

        # FORMAT MENU
        format_menu = menu.addMenu('&Format')
        format_menu.addAction(format_change_font_action)

        # VIEW MENU
        view_menu = menu.addMenu('&View')
        view_menu.addAction(view_maximize_action)

        # HELP MENU
        help_menu = menu.addMenu('&Help')
        help_menu.addAction(help_about_action)


    def toolbar(self):

        # CREATE MAIN TOOLBAR
        tool_bar = self.addToolBar('main toolbar')


        # TOOLBAR ACTION
        toolbar_new_file_action = QtGui.QAction(QtGui.QIcon('new_file.png'),
                                                '&New File', self)
        toolbar_new_file_action.triggered.connect(self.create_new_file)

        toolbar_open_file_action = QtGui.QAction(QtGui.QIcon('open_file.png'),
                                                 '&Open File', self)
        toolbar_open_file_action.triggered.connect(self.open_file)


        # ADD TOOLBAR ACTIONS
        tool_bar.addAction(toolbar_new_file_action)
        tool_bar.addAction(toolbar_open_file_action)





    def text_edit_area(self):
        text_edit = QtGui.QTextEdit()
        self.setCentralWidget(text_edit)



    def close_application(self):
        choice = QtGui.QMessageBox.question(self,
                                            'Confirmation',
                                            'Do you really want to quit?',
                                            QtGui.QMessageBox.Yes |
                                            QtGui.QMessageBox.No)
        if choice == QtGui.QMessageBox.Yes:
            sys.exit()
        else:
            pass


    def create_new_file(self):
        print('create new file')


    def open_file(self):
        print('open file')


    def save_file(self):
        print('saving file')


    def undo(self):
        print('undo')


    def maximize(self):
        print('maximize')


    def change_font(self):
        print('change font')


    def about(self):
        print('about')


def main():
    app = QtGui.QApplication(sys.argv)
    gui = Editor()
    sys.exit(app.exec_())



if __name__ == '__main__':
    main()

Answer 1

You either create an instance attribute that stores a reference to the QTextEdit

self.text_edit = QtGui.QTextEdit()

or you retrieve a reference by calling the centralWidget() method of QMainWindow

Answer 2

You should create your own custom QTextEdit. Some class that inherit from QTextEdit and personalize the way you want.

There are many cool tutorials you could go based on.

Here is a really amazing one. Helped me a lot in the very beginning.