Dropdown box not triggering the OnChange Event

[G Gabriel]

Re: Dropdown box not triggering the OnChange Event

Jeff:
Some clarification as to how arrays work is in order:
1-You need array.dump() to show the elements of the array.
2-You do not need the "r" flag in this case.
3-Dynamically populated means you do not tell alpha what are the elements of the array but rather alpha goes and collect those elements from a table or something else
4-In your case, you did tell alpha what the elements are since you specified the colors in the function. Every time you run this functions, it will show the SAME colors you specified, hence the array that appears in the first dropdown is populated statically not dynamically, populated by you not by alpha.
5-array.delte() or ARRAY.CLEAR() is a whole lot faster than iterating over each element of the array

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

Jeff:
Some clarification as to how arrays work is in order:
1-You need array.dump() to show the elements of the array. Which is what I used.
2-You do not need the "r" flag in this case. You do in fact... See the addition in red to the post above...
3-Dynamically populated means you do not tell alpha what are the elements of the array but rather alpha goes and collect those elements from a table or something else. I think some would agree with me that what I'm doing with my array is technically "dynamic population"
4-In your case, you did tell alpha what the elements are since you specified the colors in the function. Every time you run this functions, it will show the SAME colors you specified, hence the array that appears in the first dropdown is populated statically not dynamically.
5-array.delte() is a whole lot faster than iterating over each element of the array. Again, See the addition in red to the post above... .delete works great if you know the position of the value you would like to remove from the array...

Gabe, you're right... the array is STATIC, but the values in the array are NEVER static. There is no FIRST dropdown. The user can select a color from any one of the five dropdowns first. Therefore, it is impossible to determine what the values of the list for any of the dropdowns is going to be. I have attached my database in a previous post...if you would like to see it in action.

[G Gabriel]

Re: Dropdown box not triggering the OnChange Event

I am glad we are making some progress..
The first array, it does not matter where you invoke it from, it comes from your function and in THAT FUNCTION there is a pre-determined list of colors that YOU specified, hence that first list of elements is pre-determined, i.e., it's static.

The second array will be the first array less the chosen color.

Yes you can determine the position of any element in an array: use array.find() and thus you can delete that element with array.clear(), or word_substract().

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

I am glad we are making some progress..
The first array, it does not matter where you invoke it from, it comes from your function and in THAT FUNCTION there is a pre-determined list of colors that YOU specified, hence that first list of elements is pre-determined, i.e., it's static.

The second array will be the first array less the chosen color.

Yes you can determine the position of any element in an array: use array.find() and thus you can delete that element with array.clear(), or word_substract().

Are you saying it's faster to call 2 methods to remove one item in an array than it is to use two for loops?!? I wonder how array.find() locates the item in the list anyway? A loop perhaps? It probably is faster than my code... I'll test it.

I don't know if you call this progress... :D j/k
There's only ONE array. If you go look at my code (posted in the initial post) you'll see this:

' Loop through the array containing all of the colors.
' Compare the each color with the five color fields on the form.
' IF we find a match... set that color = "".
FOR j = 1 TO 19 STEP +1
FOR i = 1 TO 5 STEP +1
IF (color[j] = eval(arrayFld+alltrim(str(i))+".value"))
color[j] = ""
END IF
NEXT
NEXT

[G Gabriel]

Re: Dropdown box not triggering the OnChange Event

arrays function more like a table with an index. with array.find(), you should be able to locate the chosen element and with array.clear() alpha goes straight to that element and remove it from the array.

Of course it's faster, even if we assume that alpha iterates over the array to find that element, it will stop once it finds it and won't have to iterate over the entire list.

In fact, since you specify the original colors, You know where is that particular element is and you could send alpha straight to that element and avoid the iteration .

Yes, I know there is one array. You indicated that you want to present the user with a list of colors, when the user chooses one color, and when you move to the second dropdown, you want the original array that have all the colors to show all the colors except the color the user chose so you do not have the same color for the front and the back.

That "second" array is the "first" one less the chosen color. It is not the same array, the elements are different now.

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

arrays function more like a table with an index. with array.find(), you should be able to locate the chosen element and with array.clear() alpha goes straight to that element and remove it from the array.

Of course it's faster, even if we assume that alpha iterates over the array to find that element, it will stop once it finds it and won't have to iterate over the entire list.

In fact, since you specify the original colors, You know where is that particular element is and you could send alpha straight to that element and avoid the iteration .

Yes, I know there is one array. You indicated that you want to present the user with a list of colors, when the user chooses one color, and when you move to the second dropdown, you want the original array that have all the colors to show all the colors except the color the user chose so you do not have the same color for the front and the back.

That "second" array is the "first" one less the chosen color.

Although this discussion has gotten seriously off track, you make a fine point! I do appreciate your ideas and our discussions. :) I think that main thing we can take from this is that there are many ways of acomplishing the same thing.

FOR j = 1 TO 19 STEP +1
FOR i = 1 TO 5 STEP +1
     IF (color[j] = eval(arrayFld+alltrim(str(i))+".value"))
          color[j] = ""
          [COLOR=red]exit for[/COLOR]
     END IF 
NEXT
NEXT

Adding the exit for to my function should speed things up!

[G Gabriel]

Re: Dropdown box not triggering the OnChange Event

if you wish to keep the same function you have and speed things up, put an escape script for the inner FOR loop once there is a color match so you do not have to check all five fields:

FOR j = 1 TO 19 STEP +1
FOR i = 1 TO 5 STEP +1
IF (color[j] = eval(arrayFld+alltrim(str(i))+".value"))
color[j] = ""
go to match:
END IF
NEXT
Match:
NEXT

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

That's kinda the same as doing the exit for. Just for kicks... I'm trying to get this to work:

FOR i = 1 TO 5 STEP +1
      color.delete(color.find(eval(arrayFld+alltrim(str(i))+".value")),1)
NEXT

For some reason it's not removing any colors. do you see why? I got it... the eval(arrayFld+alltrim(str(i))+".value") is returning a CR-LF at the end.

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

This works...

FOR i = 1 TO 5 STEP +1
  field = strip_trailing_char(eval(arrayFld+alltrim(str(i))+".value"),crlf())
  num = color.find(field)
  color.delete(num,1)
 NEXT

There are tons of function calls in this. I'm going to do some testing on the two versions to see which one works faster.

After all of this.... my original problem is still unsolved....

or even more consice:

FOR i = 1 TO 5 STEP +1
color.delete(color.find(strip_trailing_char(eval(arrayFld+alltrim(str(i))+".value"),crlf())),1)
NEXT

[G Gabriel]

Re: Dropdown box not triggering the OnChange Event

Jeff:
from what Selwyn says, it worked fine for him. I didn't open your zip file. No point if Selwyn already checked it.

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

Where did he say that?

[G Gabriel]

Re: Dropdown box not triggering the OnChange Event

I created a test database to duplicate the problem, but in my test database, it works ok. I don't believe that there is a generic bug here.

There may be something specific to your database, but since you did not post an example that shows how to duplicate the problem, we can't be sure.

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

He, didn't actually open my database. He just created a simple form with a couple of fields and a dropdown box and dynamically populated it.

Would you mind looking at my program? See if you have the same problem?

[Jeff@Listbrokers]

Re: Dropdown box not triggering the OnChange Event

After following Gabe's suggestion of using the .find and .delete functions I was able to derive a significant increase in speed from my original function.

Speed comparison for the two versions of my function:

My original function had a consistent runtime of .063 secs

FOR j = 1 TO 19 STEP +1
    FOR i = 1 TO 5 STEP +1
          IF (color[j] = eval(arrayFld+alltrim(str(i))+".value"))
               color[j] = ""
          END IF     
       NEXT
    NEXT

The second version had a consistent runtime of .016 secs

FOR i = 1 TO 5 STEP +1
color.delete(color.find(strip_trailing_char(eval(arrayFld+alltrim(str(i))+".value"),crlf())),1)
NEXT

Thanks again, Gabe!

[Mike Wilson]

Re: Dropdown box not triggering the OnChange Event

Jeff,
I am a little confused. Clear one thing up for me please. Do you or do you not want two of the Font color fields to have the same value? It seems that if you are trying to eliminate the color just chosen from the array to populate the next choice list, then the answer I imagine is NO, you want the Font fields to be singular. Correct?

I, like Gabriel thought there was and order to the entries and there was an orderly sequence, and the process was to reduce the list so not to have duplicate colors.