Create objects obj0 through objN in Python, for arbitrary N?

Question

I'm working on a GUI and I'd like to create a variable number of buttons, depending on what is input by user. How should I go about this?

More precisely, the user opens a data file with a number of datasets, N. I would like to create N buttons with the ith button having the name of the ith dataset.

Something like... (conceptually, obviously this won't work)

import wx

# create sizer
hbox1=wx.GridBagSizer(4,4)

# create file button and add to sizer
fbtn = wx.Button(dv, label=file)
hbox1.Add(fbtn, pos=(jf,0))

# read file to get dataset names
dsetnames=[<dataset names for file>]

# create bottons for datasets found in file
jd=0 # datasets
for ds in dsetnames:
  self.dbtn<jd> = wx.Button(dv, label=ds)
  hbox1.Add(self.dbtn<jd>, pos=(jd,1))
  jd+=1

Thank you.

I found a solution but I don't have the privilege yet to answer questions, so I'll add it here. Generally, the solution here is to create a dictionary with the object names as the keys and the objects as the values.

import wx

dv=wx.Panel(self)
# create sizer
hbox1=wx.GridBagSizer(4,4)

# create file button and add to sizer
# filename file input by user
fbtn = wx.Button(dv, label=file)
hbox1.Add(fbtn, pos=(jf,0))

# read file to get dataset names
dsetnames=[<dataset names for file>]

# create empty dictionary for objects
self.dbtn=dict()    

# create bottons for datasets found in file
jd=0 # datasets
for ds in dsetnames:
  objname=ds
  self.dbtn.update({objname:wx.Button(dv, label=ds)}) # update dictionary with individual objects
  hbox1.Add(self.dbtn[objname], pos=(jd,1))
  jd+=1

I believe the following may be related.

Create Hash for Arbitrary Objects?

Use list of button objects – Andrew Svetlov Sep 09 '14 at 13:54 — Andrew Svetlov, Sep 09 '14 at 13:54

score 0 · Accepted Answer · answered Sep 09 '14 at 15:50

I prefer using a list so that the items read from the file are in the correct order. Dictionaries do not have a standard order, although you could use an OrderedDict from the collections library. Anyway, here's an approach that uses a list:

import wx

########################################################################
class MyPanel(wx.Panel):
    """"""

    #----------------------------------------------------------------------
    def __init__(self, parent):
        """Constructor"""
        wx.Panel.__init__(self, parent)

        btn_list = self.getButtons()

        btn_sizer = wx.BoxSizer(wx.VERTICAL)

        for index, btn in enumerate(btn_list):
            name = "button%i" % index
            b = wx.Button(self, label=btn, name=name)
            b.Bind(wx.EVT_BUTTON, self.onButton)
            btn_sizer.Add(b, 0, wx.ALL|wx.CENTER, 5)

        self.SetSizer(btn_sizer)

    #----------------------------------------------------------------------
    def getButtons(self):
        """
        Here you would put code to get a list of button labels from a file
        """
        return ["alpha", "bravo", "charlie"]

    #----------------------------------------------------------------------
    def onButton(self, event):
        """"""
        btn = event.GetEventObject()
        print "The button's label is '%s'" % btn.GetLabel()
        print "The button's name is '%s'" % btn.GetName()


########################################################################
class MyFrame(wx.Frame):
    """"""

    #----------------------------------------------------------------------
    def __init__(self):
        """Constructor"""
        wx.Frame.__init__(self, None, title="Buttons")
        panel = MyPanel(self)
        self.Show()

if __name__ == "__main__":
    app = wx.App(False)
    frame = MyFrame()
    app.MainLoop()

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Thanks I didn't realize that was an option also. – jpf Sep 14 '14 at 22:12 — jpf, Sep 14 '14 at 22:12

Create objects obj0 through objN in Python, for arbitrary N?

1 Answers1