Question

I’m trying to manipulate a listbox in Tkinter but I’m having some troubles. I used to have everything in one class, on one page, and it worked fine. I separated the methods into different classes on two different pages (one for displaying things, one for modifying them) and now I’m having some issues.

I’m getting the following error AttributeError: Actions has no attribute ‘listbox’. I’m assuming it’s something inheritance related because it worked fine before I split it into two files.

Here’s the first file

from Tkinter import *
import Tkinter
import SortActions

class MakeList(Tkinter.Listbox):

    def BuildMainWindow(self):
        menubar = Frame(relief=RAISED,borderwidth=1)
        menubar.pack()

        mb_file = Menubutton(menubar,text='file')
        mb_file.menu = Menu(mb_file)
        mb_file.menu.add_command(label='open', command = self.BuildListbox)
        mb_file.pack(side=LEFT)

        mb_edit = Menubutton(menubar,text='edit')
        mb_edit.menu = Menu(mb_edit)
        mb_edit.pack(padx=25,side=RIGHT)

        mb_file['menu'] = mb_file.menu
        mb_edit['menu'] = mb_edit.menu
        return 

    def BuildListbox(self):
        self.listbox = Tkinter.Listbox()
        index = SortActions.Actions()
        self.listbox.bind('<<ListboxSelect>>', index.GetWindowIndex)
        MoveItem = SortActions.Actions()
        self.listbox.bind('<B1-Motion>', index.MoveWindowItem)
        for item in ["one", "two", "three", "four"]:
            self.listbox.insert(END, item)    
        self.listbox.insert(END, "a list entry")
        self.listbox.pack()
        #print self.listbox.get(0, END)
        return

if __name__ == '__main__':
    start = MakeList()
    start.BuildMainWindow()
    mainloop()

And the second file, the one that I’m having issues with

from FileSort import MakeList


class Actions(MakeList):

    #gets the current item that was clicked in the window
    def GetWindowIndex(self, event):
        w = event.widget
        self.curIndex = int(w.curselection()[0])

    #moves the current item in the window when clicked/dragged
    def MoveWindowItem(self, event):
        i = self.listbox.nearest(event.y) #here is where the error is occurring 
        print i

I assumed since I inherit the MakeList class I should have access. I also tried changing it so I directly accessed MakeList (an object) but instead of the error saying “Actions instance has no….” it said “MakeList has no attribute…”

I posted something previously but I accidentally ran an older version of the code, so I was referencing the wrong error. Sorry if you saw that post. It’s gone now

Answer 1

As I see it, there’s no reason for the Actions to be in a class …

#SortActions.py

#gets the current item that was clicked in the window
def GetWindowIndex(self, event):
    w = event.widget
    self.curIndex = int(w.curselection()[0])

#moves the current item in the window when clicked/dragged
def MoveWindowItem(self, event):
    i = self.nearest(event.y) #here is where the error is occurring 
    print i

Now you can use the actions:

   ...
   def BuildListbox(self):
        #self.listbox = Tkinter.Listbox()  #??? This has no master widget ...
        #Since this is already a listbox, there's no point in building another ...

        self.bind('<<ListboxSelect>>', lambda e:SortActions.GetWindowIndex(self,e))

        self.bind('<B1-Motion>', lambda e:SortActions.MoveWindowItem(self,e)
        for item in ("one", "two", "three", "four"):
            self.insert(END, item)    
        self.insert(END, "a list entry")
        self.pack()