What is slow? Fetching the data, post-processing it on the client, or rendering it?
If it's the fetch or pre-processing, you can put up a simple loading screen overlay by using rawChildren (I believe). We do something similar.
If it's rendering, Flash Player is already busy rendering--it won't have time to render an additional loading screen. But you should not be spending that much time rendering anyway.
The events you need to react to will depend on where the slowdown occurrs.
Hi msakrejda, thank you for the reply. The slowness is caused by network and large amounts of data being transfered. I would like to add a loading screen, similar to the rawChildren method that you suggested. I just don't know which events to listen for right now to know when the dataGrid is loading data and when it has completed loading data.
The simplest way to do this would be to add the loading screen when you fire off the remote request for the data (i.e., HttpService.send() or the equivalent) and remove it in the response handler for that method. If, for some reason, you don't have access to these from the component with the grid and you are using an ArrayCollection for the DataGrid dataProvider, you could add a listener for CollectionEvent.COLLECTION_CHANGE to the dataProvider.