incubator-flex-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Carol Frampton <cfram...@adobe.com>
Subject Re: Too much validation occurring in AdvancedDataGrid
Date Wed, 07 Mar 2012 13:36:21 GMT
Did you try the same scenario with the Spark DataGrid?  More performance
work has been done on that since it was suppose to replace
mx:AdvancedDataGrid.

Carol

On 3/6/12 10 :32PM, "Justin Mclean" <justin@classsoftware.com> wrote:

>Hi,
>
>Is a bit quiet around here so I thought I bring up something odd I found
>a while ago.
>
>If you run the sample found here on the whiteboard:
>
>http://svn.apache.org/viewvc/incubator/flex/whiteboard/jmclean/datagrid/sr
>c/TooMuchValidation.mxml
>
>and move the mouse about you'll see how many times validiateNow is being
>called for each cell.
>
>If you move sideways cell to cell you sell that each cell is the row is
>validated twice and the first cell 4 times
>
>If you move up or down a row you'll see that each cell in both rows are
>validated and the first cells twice.
>
>Obviously this could be optimised. With large datagrids (and custom item
>renderers) this slows down things a little.
>
>So a few questions:
>
>Why is the first cell in each row being validated more than once? (I've
>not worked this out so far).
>
>One of the validateNow is being called from drawItem in AdvancedList Base
>(line 4800 or so) like so:
>
>        if (item is IFlexDisplayObject)
>        {
>            if (item is IInvalidating)
>            {
>                IInvalidating(item).invalidateDisplayList();
>                IInvalidating(item).validateNow();
>            }
>        }
>
>
>Do we need to call invalidateDisplayList as validateNow would also call
>updateDisplayList right? As no properties are changed on the item (as far
>as I can tell) I'm not even sure we need to call validateNow at all
>perhaps just invalidateDisplayList is enough? Does drawItem need to
>called at all for the entire row if moving mouse over cell left or right?
>
>Hopefully someone else has encountered into this issue and/or can cast
>some more light on it.
>
>This is not as far as I know an existing issue reported in the Adobe bug
>base.
>
>Thanks,
>Justin


Mime
View raw message