Digital Workshop

Hi

I'm having real problems getting seemingly simple listbox operations working. The listbox is populated by the user at runtime, but I then need to allow them to remove items from the list. I've tried SetSelection/ReplaceSelection(""), SetListBoxSelection/ReplaceSelection(""), storing the list in a variable with "\n" separators then searching for \n etc. The attached gives an idea about the routes I have tried, but none of them seem to produce any desirable result.

Anyone able to help point to a solution? I've searched here and can't see why the easiest method doesn't work.

Many thanks in anticipation
Dan
(Using V7.04)

Dan,

I've looked at your test.imp. I give you credit for trying all of the available approaches.
(you've got a syntax issue there with an unnecessary '+' sign after the '=' operator)
(the rest is a mixed metaphor)

Let's focus and solve one thing at a time (of the two stated objectives: delete items from LB, and replacing text in a line).
As always there are several ways to accomplish something, so others may suggest better or more direct methods.

Deleting items from Listbox (at runtime).
First, I would set Listbox properties to have a variable, eg. LB01_selected, to 'store selected text'.
Next, I'll just outline one approach you can try:
1. create a FOR LOOP to run through ALL of the lines of the ListBox (see later comments below)
2. you have a variable, 'selectedindex', for the User's choice
3. set a var revisedcontents = "";
4. make an IF statement if ( i != selectedindex)
5. then do something like this:
ListBox.SetListBoxSelection(i)
revisedcontents += LB01_selected ;
6. wait(0) //you may be able to eliminate this and see if it works without it
7. close the LOOP
8. ListBox.SetSelection(0, -1) ;
ListBox.ReplaceSelection( revisedcontents );

For the other part of the problem, here are some hints... you can explore how the following commands work together. Or, you may choose to use some other approach.

[Lar EDIT:] I have changed the index value in the 4th line above to 1 (it was 0, because I was testing those separately -- but we really want to operate on the same line)

Dan, I chose to give this to you in pieces and in outline so you can think through what is going on... and once you get a feel for it I think you'll be able to reuse these methods and extend them later.

One last thing I forgot to mention regarding: ListBox.SetListBoxSelection(1)
That command only activates a 'selection' as a pointer. I do not think it returns any value for you. But if you created the 'associated' variable for a Listbox's selected item, that is a value you can use.

Thanks Lar - I really appreciate the time you have taken there. That was one method I hadn't tried.

The only thing I had to do was store the SelectedIndex first as the original one changed during the 'For' loop. I'm also storing the number of lines in each listbox for another purpose, so used this (others would need the 'Count' first).

Attached file, should anyone need this. The bottom solution is the one that works.

Cheers again
Dan



var RevisedContents = "";
var UserSelectedIndex = SelectedIndex

for (i=0;i<NoLines;i++)
{

if (i != UserSelectedIndex)
{
ListBox3.SetListBoxSelection(i)
RevisedContents += ListText + "\n";
}

}
ListBox3.SetSelection(0, -1) ;
ListBox3.ReplaceSelection(RevisedContents );

D,
Good, you got it. And you remembered to add the +"\n" which I forgot.
(for those who might 'pick-up' on this solution, the variable 'ListText' that Dan uses is probably associated to the listbox items (in Properties) )

As a side-note, I have found some convenient uses for Listbox objects as a way a manipulating SETS of things... and that Listbox does not even have to be visible -- it can be positioned off-page. One example/use is as a way to construct a lookup table. And these match-up very well with Arrays, where you can use the same index from the User's Listbox selection, so not need extra Listbox.

Yes, that's the way I use them. I've added a scribble and an IMP to our website.

http://www.live.interaktiv.co.uk/index. ... Itemid=166

Mack

Hi

I've run into another listbox hitch. I think I must be going mad because I had this working previously in my pub (and the discussion above indicates that this wasn't an issue at the time). However, I've recreated the problem in the attached test file, so am wondering what has happened.

The trouble is that I can't select a list item using the mouse in a clone of a listbox. If I use the button to create a clone in the attached pub, I can only select the list items with the keyboard, not the mouse. The mouse continues to work in the original.

Could someone please check that this problem is an also an issue for you and not just me. I am stumped by the fact that this worked previously.

Many thanks
Dan

It'll only work if the List boxes are level with each other. As far as I'm aware, you'd need to build custom list boxes if you want to clone them.

Mack

Thanks Mack

As usual, you are spot on. I moved the original in my sample vertically downwards a few pixels and bingo. I must have lucked out with the level originally, hence it appearing to work. I'm glad I found this out now.

I'll have a look at a custom list box tomorrow. I presume I need to start with a simple text box and work from there.

Cheers
Dan

Hi Dan,

Our custom one is a frame with Text Boxes.

Mack