Hi Everyone, I think I have solved this.
I started to create a test app to illustrate the issue, and I could recreate the issue. I noticed 2 things I was doing in my main project, that I was not doing with my test app. I was adding data to the ArrayCollection using addItemAt, in my test app I simply used addItem. I was handling the updateComplete event in the Datagrid trying to set the selected Index and verticalScrollPosition. I remove the updateComplete Event handler and changed the way data was added to the ArrayCollection and voia the issue had disappeared. I hope this might help someone in the future, Mark --- In [email protected], "mark_j_ellul" <[EMAIL PROTECTED]> wrote: > > HI, > > I was wondering if anyone has come across this issue, or knows where I > should start looking for a solution. > > My project is as follows, I have a datagrid with an ArrayCollection as > its dataprovider. I use a timer to check a web service every 5 seconds > for new data, pulling a maximum of 40 rows of data at a time. > > So I start my app, and when the first set is loaded up I start to > scroll the datagrid to get to the bottom the loaded data. Then when > the timer loads up the new data into the array collection, my Datagrid > scrolls back to the top. > > The issue is that when I then scroll down, I see there are rows > between the first data that is loaded and the next that are blank. I > edit the row data this via a DoubleClick as I do the editing in a pop > up. When I try to edit one of these blank rows I receive errors, cos I > pass in the caretBookmark to gain access to the object data in my > ArrayCollection. > > I also get errors such as below, when scrolling in the datagrid with > the keyboard and mouse. > > Should I be calling something like itemUpdated in the ArrayCollection > every time I add a new item or remove an item, so the Datagrid is > notified explicitly? > > Has anyone ever come across this error? > > Any ideas on what I should be looking at to solve this? > > The blank rows seems very weird to say the least, I think maybe some > internal counter which links the rows in the ArrayCollection and > DataGrid rows must be going haywire? > > Is there a way to avoid this error? For example to stop the Datagrid > invalidating until the objects are added to the ArrayCollection and > then call an invalidation type redraw? > > Any help would be appreciated. > > Regards > > Mark > > TypeError: Error #1010: A term is undefined and has no properties. > at > mx.controls.listClasses::ListBase/mx.controls.listClasses:ListBase::scrollVertically() > at mx.controls::DataGrid/mx.controls:DataGrid::scrollVertically() > at mx.controls.listClasses::ListBase/set verticalScrollPosition() > at mx.controls::DataGrid/mx.controls:DataGrid::scrollHandler() > at > flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchEventFunction() > at flash.events::EventDispatcher/dispatchEvent() > at mx.core::UIComponent/dispatchEvent() > at > mx.controls.scrollClasses::ScrollBar/http://www.adobe.com/2006/flex/mx/internal::dispatchScrollEvent() > at mx.controls.scrollClasses::ScrollThumb/::mouseMoveHandler() >
