Forum Discussion

John_OR's avatar
John_OR
Occasional Contributor
7 years ago

Python cluelessness with lists

Hi, I'm trying to transition from VBScript to Python and having some trouble understanding lists in Python.  What I'm trying to do is find all the comboboxes in a dialog and add them to a list.  Once...
  • John_OR's avatar
    John_OR
    7 years ago

    It looks like I figured it out.  I changed :

    combos = [(dlg.FindAllChildren(QtClassName,"OnOneComboBox",7))]

     

    to

     

    combos = list(dlg.FindAllChildren(QtClassName,"OnOneComboBox",7))

     

    Removing the brackets per your suggestion and adding "list" did the trick.  Now setting the index is working and I'm able to append to the list.

     

     

     

baxatob's avatar
baxatob
Community Hero
7 years ago

Hi,

 

Try to remove square brackets from your statement:

 

combos = dlg.FindAllChildren(QtClassName,"OnOneComboBox",7)

Otherwise you will receive array in array, something like:

 

[[obj1, obj2, obj3]]
  • John_OR's avatar
    John_OR
    Occasional Contributor
    7 years ago

    Hi, thanks for the tip.  Removing the brackets works but later when I want to append to the combos list/array it's not working.  Following on from my example I tried something like this:

    combos.append (some_other_combo_here)

     

    That gives me the familiar error:  "AttributeError" 'SafeArrayWrapper' object has no attribute 'append'.

     

    Any idea how I can successfully append to combos?

     

    Thanks,

    John

  • John_OR's avatar
    John_OR
    Occasional Contributor
    7 years ago

    It looks like I figured it out.  I changed :

    combos = [(dlg.FindAllChildren(QtClassName,"OnOneComboBox",7))]

     

    to

     

    combos = list(dlg.FindAllChildren(QtClassName,"OnOneComboBox",7))

     

    Removing the brackets per your suggestion and adding "list" did the trick.  Now setting the index is working and I'm able to append to the list.

     

     

     

    • baxatob's avatar
      baxatob
      Community Hero
      7 years ago

      FindAllChildren() returns list anyway. You can omit adding a list():

       

      combos = dlg.FindAllChildren(QtClassName,"OnOneComboBox",7)

       

      • John_OR's avatar
        John_OR
        Occasional Contributor
        7 years ago

        I tried it without List() and iterating through the list and setting the index works fine.  However, if I try to append to the list I get the SafeArrayWrapper error message.  When I use List() the append works as expected.  I have no clue why.

         

        As you suggested the result should be the same but in practice it's not.