Task chaining (wait for the previous task to completed)

Question

var tasks = new List();

foreach (var guid in guids)
{
    var task = new Task( ...);
    tasks.Add(task);
}

foreach (var task in tasks)
{
    task.Star         


        

Answer 1

This is not Task Chaining.

You need to do Task chaining using ContinueWith. Last task would need to update the UI.

Task.Factory.StartNew( () => DoThis())
   .ContinueWith((t1) => DoThat())
   .ContinueWith((t2) => UpdateUi(), 
       TaskScheduler.FromCurrentSynchronizationContext());

Note the last line has TaskScheduler.FromCurrentSynchronizationContext() this will ensure task will run in the synchronization context (UI Thread).