Avoid UI locking/freezing when assigning datasource?

Question

I'm using MVP pattern, so I have a View that has almost no logic in it and a Presenter that knows how to react to the user's interactions with the view. Everytime I need to get data from a service or such my code does so asynchronously, the problem I'm having is that lets say I get 10,000 items that need to be databound to a Grid, when I assign those (marshalling them through the UI thread) my UI locks for short periods of time (because of the Grid control/CurrencyManager locking the thread I think)

Does anybody know possible ways to avoid this?

I've tried assigning the data in incremental chunks with a timer, but still ends making the UI freeze randomly

Cheers

Answer 1

You need to download the data from the server in chunks on a background thread then append them to a client side collection object. If that collection object implements INotifyCollectionChanged then the grid should update automatically. You can get this with ObservableCollection , or with Bindable Linq which may be a better choice.

The problem you will run into is that you have a grid re-drawing 10,000 items over and over again. This is generally not that good of a solution but it can work if you get a grid with UI Virtualization. For example I use the Telerik GridView control and I have had good results with around 5000 records.

Having tried to answer your question directly, let me give you some advice that may lead you in a better direction. Direct query of 10,000 items over the network isn't going to be blazing fast no matter how cool your grid control is. You may want to consider using a service bus to communicate async to the server and store a copy of the data in a local database. I am working on a project that will use Rhino Service Bus to make a smart client that can work even if the network connection goes down for a short time. The service bus approach to smart client development should make your UI locking pains go away and make your app more stable and resilient to network traffic.

Answer 2

You should use some sort of virtual data mod e for your grid. This will remove such kind of problem definitively.