Question

Ok, a bit of a strange one – and it’s probably something simple as I’m pretty new to Silverlight!

I have an object with the following property:-

private int targetID = NULL_TARGET_VALUE;
    [Display(Name="Target", Order=1)]
    [Required]
    public int TargetID
    {
        get
        {
            return targetID;
        }
        set
        {
            if (this.targetID != value)
            {
                this.ValidateProperty("TargetID", value);

                this.targetID = value;

                this.RaisePropertyChanged("TargetID");
            }
        }
    }

This object is created using the DataForm from the toolkit. I use the AutoGeneratingField event to change the item to a combo box drop down with the code below:

if (e.PropertyName == "TargetID")
        {
            ComboBox target = new ComboBox() { DisplayMemberPath = "Title", SelectedValuePath = "ItemID" };
            target.ItemsSource = TaskManager.Manager.GanttItemSource;
            var selectedItem = TaskManager.Manager.GanttItemSource.FirstOrDefault(p => p.ItemID == ParentTargetID);
            target.SelectedItem = selectedItem;
            e.Field.ReplaceTextBox(target, ComboBox.SelectedValueProperty, binding => binding.Converter = new TargetNullValueConverter());
            break;
        }

This does result in a drop down as I would expect. On my save button event I have this code:

if (registerForm.ValidateItem())
        {
            this.task.Save();
        }

If the debugger is attached to the silverlight project this works great. If it’s not then ValidateItem returns false as it thinks I have added an invalid target (“Input is not in a correct format” is the exact validation error I get).

Any ideas really appreciated! (BTW Just to confirm this happens in both release and debug build modes, simply attaching or removing a debugger causes this to occur)

Answer 1

Dammit, the issues was down to this line in the autogeneratingfield event:-

e.Field.ReplaceTextBox(target, ComboBox.SelectedValueProperty, binding => binding.Converter = new TargetNullValueConverter());

This allows it to work

                            e.Field.ReplaceTextBox(target, ComboBox.SelectedValueProperty);

Which makes sense because I’m dealing with ints not objects. Still don’t know why it works with the debugger attached however!