public Task ShowAsync(IOperationCallback callback, IDataContext context)
{
ViewModel.NotBeDisposed();
if (IsOpen)
{
throw ExceptionManager.WindowOpened();
}
var tcs = new TaskCompletionSource <object>();
RaiseNavigating(context, NavigationMode.New)
.TryExecuteSynchronously(task =>
{
try
{
if (!task.Result)
{
tcs.TrySetCanceled();
if (callback != null)
{
callback.Invoke(OperationResult.CreateCancelResult <bool?>(OperationType.WindowNavigation, ViewModel, context));
}
return;
}
if (context == null)
{
context = DataContext.Empty;
}
if (callback != null)
{
OperationCallbackManager.Register(OperationType.WindowNavigation, ViewModel, callback, context);
}
_isOpen = true;
ShowInternal(context, tcs);
}
catch (Exception e)
{
tcs.TrySetException(e);
if (callback != null)
{
callback.Invoke(OperationResult.CreateErrorResult <bool?>(OperationType.WindowNavigation, ViewModel, e, context));
}
}
});
return(tcs.Task);
}
/// <summary>
/// Shows the specified <see cref="IViewModel" />.
/// </summary>
/// <param name="callback">The specified callback, if any.</param>
/// <param name="context">The specified context.</param>
public void Show(IOperationCallback callback, IDataContext context)
{
ViewModel.NotBeDisposed();
if (IsOpen)
{
throw ExceptionManager.WindowOpened();
}
_isOpen = true;
if (context == null)
{
context = DataContext.Empty;
}
if (callback != null)
{
OperationCallbackManager.Register(OperationType.WindowNavigation, ViewModel, callback, context);
}
OnShow(context);
ShowInternal(context);
}