Destop application in Python with more than one frame!

Question

I have developed many desktop applications in Delphi / Pascal - Here I have used modal forms.

//Mainform
Form1:= TForm1.Create(Self);  
If Form1.Showmodal =mrOK then ….  
In Form1 you cal call vars in Mainform like mainform.X := 1  

(I know – I normaly use try,except, finally)

I will now switch to Python and my problem is the following:

I want an application with a main window (frame) where you can call a number of forms which can have Forms and so on

I can make a program with python and wxpython where a main frame create a new frame and show it – But how do I get back – and how to I have reference to the parent frame – if its possible!

From mainform

Def OnButton1(self, event):  
    self.main2 = Frame2.create(None)  
    self.main2.Show()  
    self.Hide()  

When I am done in main2 who do I return to mainform – It’s hidden !!

I know I can use dialog, but I need a normal frame!! What I am looking for is a small program where have a mainframe – with a button that calls a Frame (Frame1) who have a button that calls a frame (Frame1A)

I am new to Python but have made many applications in C,C++, Pascal I have looked at almost all demos, but none of them could give me a hint!

Regards Mick

Answer 1

Just curious, why can't you use a dialog?

Anyway, a simple solution would be to provide a callback function to the constructor of Frame2, which is called when Frame2 is about to be closed.

class Frame2(wx.wxFrame):
    def __init__(self, parent, callback, ...)
        wx.wxFrame(self, parent)
        self._callback = callback
        self.bind(wx.EVT_CLOSE, self.OnClose(), self)

    def OnClose():
        self.Destroy()
        self._callback()

class Frame1(...):
    ...

    def OnButton1(self, event):
        self.main2 = Frame2(self, self.OnButton1Callback)
        self.main2.Show()
        self.Hide()

    def OnButton1Callback(self)
        self.Show()

    ...

The code above is just a hint, has been never tested!

Answer 2

There are several ways to get a reference to the main frame. When you create the secondary frames, you can pass them either None or a parent. If you pass the main frame as the parent, then you have an easy way to reference it.

Alternatively, you can do this:

topFrame = wx.GetTopLevelParent()

As for showing a secondary frame and hiding the main one, what I do is use Pubsub. When I open the secondary frame, I hide the main one. When I close the secondary frame, it sends a pubsub message to the hidden main frame that is caught and the main frame is re-shown.

There are lots of pubsub examples on the wxPython wiki. There's also this article I wrote:

http://www.blog.pythonlibrary.org/2010/06/27/wxpython-and-pubsub-a-simple-tutorial/

Hope that helps!