Wait until data is loaded from a server with json

On other platforms I've used, a writer can lock the table. It will not write until it gets the lock. The reader if it issues a read will block until the lock is removed by the writer. On many systems this is effisent as no polling is involved the system only checks when lock states change

 

Sounds like you're going about it the wrong way. You should let the tableView go ahead and load empty when the view is loaded. Once the data has been downloaded and stored in your datasource you should set up a delegate method in your table view controller to update the table view to display your new data.

A great way to update the table view is:

Code:

[tableView beginUpdates];

// insert some rows, do whatever updates

[tableView endUpdates];

That will animate all of the updates in the begin/end block in a very nice way. It's pretty neat. For more information check out the documentation on UITableView.

http://developer.apple.com/library/...ce/UITableView_Class/Reference/Reference.html

 

If you like you can add a row to the table that says Loading... or something like that and then remove it when the data arrive.

LazyTableImages does something like this.

 

There is a sample named LazyTableImages in xcode help document.
I think it's just what you wanted.