New Features in Silverlight 3

Re: vb version

andrewaggb — Fri, 28 Aug 2009 16:39:37 GMT

you could try

http://www.developerfusion.com/tools/convert/csharp-to-vb

http://www.carlosag.net/Tools/CodeTranslator/

I've used similiar tools in the past to convert vb to c# (I know you're going the other way) and they work ok. They get 80-90% of it right from my experience.

Re: Re: Re: Re: Re: Datepicker problem or bug?

estern — Sat, 25 Jul 2009 16:02:40 GMT

unforetuneately I'm using vb, translation of the above solutions is not going well, is there a vb solution for this problem?

Re: Re: Re: Re: Datepicker problem or bug?

wackyphill — Fri, 24 Jul 2009 19:11:04 GMT

This was broken in the Beta. I don't really know why it wasn't fixed for RTM. I have a hard time believing no one could find a way.

Re: Re: Re: Re: Datepicker problem or bug?

estern — Fri, 24 Jul 2009 18:49:06 GMT

I've just spent 4 hours chasing this problem. Thanks for the suggestions and workarounds. Doesn't a regression like this warrant a hotfix?

Re: Re: Re: Datepicker problem or bug?

Brian Braeckel — Wed, 22 Jul 2009 19:40:35 GMT

Another possible workaround is to hook up to the DataGrid's CellEditEnding event and finalize the DatePicker's value. The DatePicker doesn't typically finalize its value until LostFocus, but this will cause it to do so synchronously.

void dataGrid_CellEditEnding(object sender, DataGridCellEditEndingEventArgs e)
{
    DatePicker datePicker = e.EditingElement as DatePicker;
    if (datePicker != null)
    {
        Queue children = new Queue();
        children.Enqueue(datePicker);
        while (children.Count > 0)
        {
            DependencyObject child = children.Dequeue();
            TextBox textBox = child as TextBox;
            if (textBox != null)
            {
                datePicker.Text = textBox.Text;
                return;
            }
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(child); i++)
            {
                children.Enqueue(VisualTreeHelper.GetChild(child, i));
            }
        }
    }
}

Re: Re: Re: Datepicker problem or bug?

avbersSL — Thu, 16 Jul 2009 15:29:43 GMT

I was wondering what the SL team had to say about this issue....

Re: Datepicker problem or bug?

yifung — Mon, 13 Jul 2009 18:01:08 GMT

Thanks, I'm sorry about the inconvenience. This is definitely one of the worst issues in the SL 3 DataGrid.

Re: Datepicker problem or bug?

wackyphill — Sat, 11 Jul 2009 21:14:57 GMT

Unfortunately this problem still exists in SL3 RTW, but thank you yifung for the example. I had not seen a DataGridBoundColumn implementation before. I learned something.

Thanks.

Re: Re: Datepicker problem or bug?

avbersSL — Fri, 26 Jun 2009 07:26:56 GMT

I'm hitting this problem this week also, and it is very unfortunate..

This 'workaround' is in my opinion a dirty hack ;) so I hope the SL team is able to fix it in the final SL 3... (which will be very very final if the july 10th release date still stands..)

Re: Datepicker problem or bug?

yifung — Fri, 26 Jun 2009 01:30:20 GMT

Basak is correct. The DataGrid changed to use explicty binding for editing for Silverlight 3, and this looks like an unfortunate side effect of that change. As a workaround, please use the following DateColumn implementation. I know this isn't ideal, and even the implementation of the DateColumn below isn't ideal, but I believe it's the best choice at this time.

The usage of the DateColumn is simple. It's similar to using the TextColumn. Of course in your case, you could modify it slightly so that it has a readonly Binding and an editing Binding

        <data:DataGrid x:Name="dataGrid">
            <data:DataGrid.Columns>
                <local:DataGridDateColumn Binding="{Binding Date}" />
            </data:DataGrid.Columns>
        </data:DataGrid>

    public class DataGridDateColumn : DataGridBoundColumn
    {
        private DatePicker _datePicker;
        private TextBox _textBox;

        protected override FrameworkElement GenerateEditingElement(DataGridCell cell, object dataItem)
        {
            if (_datePicker == null)
            {
                _datePicker = new DatePicker();
                _datePicker.SetBinding(DatePicker.SelectedDateProperty, this.Binding);
            }
            return _datePicker;
        }

        protected override FrameworkElement GenerateElement(DataGridCell cell, object dataItem)
        {
            TextBlock textBlock = new TextBlock();
            textBlock.Margin = new Thickness(6);
            textBlock.VerticalAlignment = VerticalAlignment.Center;
            textBlock.SetBinding(TextBlock.TextProperty, this.Binding);
            return textBlock;
        }

        protected override object PrepareCellForEdit(FrameworkElement editingElement, RoutedEventArgs editingEventArgs)
        {
            if (_textBox == null)
            {
                SetUpTextBox(_datePicker);
            }
            return _datePicker.SelectedDate;
        }

        private void SetUpTextBox(DependencyObject parent)
        {
            _textBox = parent as TextBox;
            if (_textBox == null && parent != null)
            {
                for (int i = 0; i < VisualTreeHelper.GetChildrenCount(parent); i++)
                {
                    SetUpTextBox(VisualTreeHelper.GetChild(parent, i));
                    if (_textBox != null)
                    {
                        break;
                    }
                }
            }
            if (_textBox != null)
            {
                _textBox.TextChanged += TextBox_TextChanged;
            }
        }
        
        private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
        {
            string dateText = _textBox.Text;
            DateTime date;
            if (DateTime.TryParse(dateText, out date))
            {
                _textBox.TextChanged -= TextBox_TextChanged;
                int selectionStart = _textBox.SelectionStart;
                int selectionLength = _textBox.SelectionLength;
                _datePicker.SelectedDate = date;
                this.Dispatcher.BeginInvoke(delegate
                {
                    _textBox.Text = dateText;
                    _textBox.SelectionStart = selectionStart;
                    _textBox.SelectionLength = selectionLength;
                    _textBox.TextChanged += TextBox_TextChanged;
                });
            }
        }
    }

Re: Re: Re: Datepicker problem or bug?

wackyphill — Thu, 25 Jun 2009 22:57:52 GMT

Thank you.

Re: Re: Re: Datepicker problem or bug?

basak — Thu, 25 Jun 2009 17:54:54 GMT

I am a part of the dev team and I was talking about the DatePicker behaviour outside of a DataGrid since nothing has changed in that area in DatePicker since SL2. But the behaviour of DataGrid has changed. I let the teams know about the issue.

Re: Re: Datepicker problem or bug?

wackyphill — Thu, 25 Jun 2009 02:36:59 GMT

OK.....Well I'm not sure if you've actually ever used Silverlight 2 before or not but you don't seem to know what you're talking about.

Here's a link to a very basic Silverlight 2 program written in 5 minutes to demonstrate that in Silverlight 2 if you place a DatePicker in a Datagrid you can type a date in to it, tab to a new cell, and your date will remain.

http://www.sendspace.com/file/7fqli7

I'm hoping someone out there who might be in a position to let the SL3 devs know, would please do so. This seems to be broken in SL3.

Re: Re: Datepicker problem or bug?

basak — Wed, 24 Jun 2009 17:45:34 GMT

It was the same behavior in Silverlight 2. SelectedDate was only committed when Enter key is hit. Can you please post all your project?

Re: Datepicker problem or bug?

wackyphill — Mon, 22 Jun 2009 22:14:54 GMT

Really? Silverlight 2 doesn't work that way. Why change the expected behavior in Silverlight 3?

Plus that's really unintuitive for a user. I have a hard time imagining anyone would want that behavior. When you type into a textbox you expect what you entered to remain unless what you typed was invalid. I can't think of a UI I've used in the past that requires the Enter key be pressed.