Edit filtered ArrayCollection messes up Datagrid

Question

I understand Datagrid + itemrenderer is a frustrating issue
sometimes. After Googling around, I got no luck solving my problem.
It goes like this:
I have an ArrayCollection
objectArray as the dataprovider for a datagrid. I applied a
filtered function on
objectArray and the datagrid displayed the filtered array
with no problem. However, when I looped through the filtered array
and made some changes, the datagrid went crazy. The order got
changed and some of the changed values didn't show up as changed.
Did anyone come across the same issue? Can anyone give me
some idea of what's going on?
Thanks.

Answer 1

mmm...
Filter should be working, lets try to change Item for object.
private function changeValue():void {
for each (var item:Object in myArray) {
item.value = true;
myArray.refresh();
"scabbage" <[email protected]> wrote in
message
news:[email protected]...
> Ok, I think I found where the problem is. My code looks
like this:
>
>
>
> ----------
> <mx:Script>
> <![CDATA[
>
> private function applyFilter():void {
> myArray.filterFunction = myFilter;
> myArray.refresh();
> }
>
> private function changeValue():void {
> for each (var item:Item in myArray) {
> item.value = true;
> }
> myArray.refresh();
> }
>
>
> // simple filter
> private function myFilter(item:Object):void {
> if (item.id > 5 && item.id < 20)
> return true;
> else
> return false;
> }
>
> ]]>
> </mx:Script>
>
> <mx:DataGrid dataProvider="{myArray}"/>
> <mx:Button label="filter" click="applyFilter()"/>
> <mx:Button label="change value"
click="changeValue()"/>
>
>
>
> -------------------------
>
> So what causes the problem is the "changeValue"
function. Solution to my
> problem: bring "myArray.refresh()" inside the loop. So
instead of doing a
> refresh after all the values are changed, refresh the
array EVERY TIME you
> change a value. I realized that without doing this, the
"for each" loop
> doesn't
> loop through the filtered array correctly. Some items
gets accessed twice
> and
> some don't get accessed at all. This explains the "true,
false, true,
> false,
> ..." alternating result I got previously.
>
> However, I was not able to reproduce this problem using
a 5000-item toy
> ArrayCollection (different objects). Flex made the right
value changes
> with
> only one array refresh at the end.
>
>
>
quote:
Originally posted by:
Newsgroup User
> Sorry.. I can't help you without see some code.
> Rgds
>
> JFB
>
>
> "scabbage" <[email protected]> wrote in
message
> news:[email protected]...
> > JFB,
> >
> > I followed what you said and did a
myArray.refresh() after I changed all
> > my
> > myArray.someProperty from false to true (myArray is
the filtered array).
> > However, in the Datagrid, the someProperty column
didn't show "true"
> > everywhere, but with true and false alternating
(false, true, false,
> > true,
> > false...) across the datagrid. Any idea how this
coud be solved?
> >
> > Thanks.
> >
>
>
>
>
>
>