[FIXED] Pyqt check when other window is closed

Issue

Lets say I have 2 windows, one of which opens the other on a menu item click:

class ProjectWindow(QtWidgets.QMainWindow, project_window_qt.Ui_ProjectWindow):
    def __init__(self):
        super(ProjectWindow, self).__init__()

        # Setup the main window UI
        self.setupUi(self)
        self.new_project_window = None

        # Handle menu bar item click events
        self.actionNewProject.triggered.connect(self.new_project)

    def new_project(self):
        self.new_project_window = project_new_window.NewProjectWindow()
        self.new_project_window.show()

    def refresh_projects(self):
        with open(os.path.join(self.directory, 'projects.txt'), 'r') as f:
            projects = json.load(f)

        return projects

and

class NewProjectWindow(QtWidgets.QDialog, project_new_window_qt.Ui_NewProjectWindow):
    def __init__(self,):
        super(NewProjectWindow, self).__init__()

        # Setup the main window UI
        self.setupUi(self)

Once the user closes new_project_window, I want the refresh_projects method to be called in the ProjectWindow class.

I thought about setting up an event listener to check when new_project_window is closed, and then call refresh_projects once that happens, but the window just closes immediately after it opens:

def new_project(self):
    self.new_project_window = project_new_window.NewProjectWindow(self.directory, self.project_list)
    self.new_project_window.onClose.connect(self.refresh_projects)
    self.new_project_window.show()

Is that the correct approach? Or is there a way to call refresh_projects directly from within the new_project_window object?

Solution

If you are using QDialog you should call exec_() instead of show(), this will return a value when the user closes the window, and just call refresh project.

def new_project(self):
    self.new_project_window = project_new_window.NewProjectWindow(self.directory, self.project_list)
    code = self.new_project_window.exec_()
    """code: gets the value of the QDialog.Accepted, or QDialog.Rejected 
    that you can connect it to some accept button
    using the accept() and reject() functions.
    """
    self.refresh_projects()

exec_() is blocking, ie the next line is not executed unless the QDialog has been closed.

Answered By - eyllanesc