Folderitem.constructor from listbox

General
1

[code] for i = 0 to FilesListbox.ListCount step 1

    Dim openfile As FolderItem
    
    openfile.constructor(FilesListBox.cell(i,0),openfile.PathTypeAbsolute) // <----- This line is producing a NilObjectException bug... WHAT DID I DO?!
    
    if openFile <> nil and openfile.Exists then
      Window1.AddFile(openFile)
    end
    
  next[/code]

What have I done wrong here.

Thank you so much

2

Listbox rows are zero based. The listbox.Listcount is not. Your cell(i, 0) is going out of bounds on the last iteration

Try…
for i = 0 to FilesListbox.ListCount-1 //step 1 <- is not needed

3

openFile IS nil, so can’t call any method on it. What’s more, this is not the way you’d call the Constructor anyway.

dim openFile as FolderItem
openFile = new FolderItem( path, type )

or simply:

dim openFile as new FolderItem( path, type )

The “new” operator will call the appropriate constructor based on the parameters you’ve given.

4 
openfile.constructor(FilesListBox.cell(i,0),openfile.PathTypeAbsolute)

This is invalid syntax for invoking the Constructor method. Constructors are (almost) never called by name but rather by using the New keyword and the name of the class.

openfile = New FolderItem(FilesListBox.cell(i,0),openfile.PathTypeAbsolute) ' invokes the Constructor method

You are receiving a NilObjectException in your original code because the object openfile is Nil. You cannot call a method (even Constructor) on a Nil object.

5

Now, I seem to be getting an OUTOFBOUNDSEXCEPTION error with the code:

[code] for i = 0 to FilesListbox.ListCount step 1

    dim openFile as FolderItem
    openFile = new FolderItem(FilesListBox.cell(i,0),openfile.PathTypeAbsolute) <--- OUTOFBOUNDSEXCEPTION error same line as before
    
    if openFile <> nil and openfile.Exists then
      AddFile(openFile)
    end
    
  next[/code]

Now what :frowning:

Thanks you all!

6 
for i = 0 to FilesListbox.ListCount-1
7

AND THE MAGIC HAPPENED!

8

Not for nothing, but Roger posted that in the second post in this thread.

9

Missed it and reallocated credit for the completion. Thanks for keeping me fair!

10

Cool. And if you haven’t already, you’ll have plenty of opportunities to give @Michel Bujardet credit in the future. We all have. :slight_smile:

11

Indeed Roger gave the solution right away. That base 1 and zero things happens so often, we all have been bitten !

12

One of the best changes in the new framework is making everything zero-based.

13

Indeed.