How do I pass information between pages of a wxPython PyWizardPage wizard?

Question 1

You could pass the values around as msvalkon mentioned. However I think subclassing wx.wizard.Wizard would be simpler. Then you can just create the various widgets inside the class and the their parents to different pages. This allows you to access the variables across pages rather easily. Here's an expansion on the answer I gave to your last question:

import wx
import wx.wizard

class WizardPage(wx.wizard.PyWizardPage):
    def __init__(self, parent, title):
        wx.wizard.PyWizardPage.__init__(self, parent)
        self.next = None
        self.prev = None
        self.initializeUI(title)

    def initializeUI(self, title):      
        # create grid layout manager    
        self.sizer = wx.GridBagSizer()
        self.SetSizerAndFit(self.sizer)

    def addWidget(self, widget, pos, span): 
        self.sizer.Add(widget, pos, span, wx.EXPAND)

    # getters and setters 
    def SetPrev(self, prev):
        self.prev = prev

    def SetNext(self, next):
        self.next = next

    def GetPrev(self):
        return self.prev

    def GetNext(self):
        return self.next

########################################################################
class MyWizard(wx.wizard.Wizard):
    """"""

    #----------------------------------------------------------------------
    def __init__(self):
        """Constructor"""
        wx.wizard.Wizard.__init__(self, None, -1, "Some Title")
        self.SetPageSize((500, 350))

        mypage1 = self.create_page1()

        forward_btn = self.FindWindowById(wx.ID_FORWARD) 
        forward_btn.Disable()

        self.timer = wx.Timer(self)
        self.Bind(wx.EVT_TIMER, self.onUpdate, self.timer)
        self.timer.Start(1)

        self.RunWizard(mypage1)

    #----------------------------------------------------------------------
    def create_page1(self):
        page1 = WizardPage(self, "Page 1")
        d = wx.StaticText(page1, label="test")
        page1.addWidget(d, (2, 1), (1,5))

        self.text1 = wx.TextCtrl(page1)
        page1.addWidget(self.text1, (3,1), (1,5))

        self.text2 = wx.TextCtrl(page1)
        page1.addWidget(self.text2, (4,1), (1,5))

        page2 = WizardPage(self, "Page 2")
        page2.SetName("page2")
        self.text3 = wx.TextCtrl(page2)
        self.Bind(wx.wizard.EVT_WIZARD_PAGE_CHANGED, self.onPageChanged)
        page3 = WizardPage(self, "Page 3")

        # Set links
        page2.SetPrev(page1)
        page1.SetNext(page2)
        page3.SetPrev(page2)
        page2.SetNext(page3)

        return page1

    #----------------------------------------------------------------------
    def onPageChanged(self, event):
        """"""
        page = event.GetPage()
        print
        if page.GetName() == "page2":
            self.text3.SetValue(self.text2.GetValue())

    #----------------------------------------------------------------------
    def onUpdate(self, event):
        """
        Enables the Next button if both text controls have values
        """
        value_one = self.text1.GetValue()
        value_two = self.text2.GetValue()
        if value_one and value_two:
            forward_btn = self.FindWindowById(wx.ID_FORWARD) 
            forward_btn.Enable()
            self.timer.Stop()

#----------------------------------------------------------------------
def main():
    """"""
    wizard = MyWizard()

#----------------------------------------------------------------------
if __name__ == "__main__":
    app = wx.App(False)
    main()
    app.MainLoop()

The idea here is to give each page a unique name and then catch the EVT_WIZARD_PAGE_CHANGED. In the handler, you can check what page you're on and update its contents accordingly.

Question 2

I'm not entirely sure what the most idiomatic way of doing it is but here's how I've dealt with this previously.

Subclass the wx.wizard.Wizard-class and bind the wx events wx.wizard.EVT_WIZARD_ON_PAGE_CHANGING and wx.wizard.EVT_WIZARD_ON_PAGE_CHANGED to methods of your class which make sure that data is consistently transferred back and forth pages.

The wx.wizard.EVT_WIZARD_ON_PAGE_CHANGING will be triggered when you press next. The method which handles this event is responsible for saving the current pages data.

The wx.wizard.EVT_WIZARD_ON_PAGE_CHANGED will trigger when the page has actually changed. The method which handles this event is responsible for populating the data from the previous page to the current pages fields or do whatever it is that you want to do with it.