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Means of generating an editable form from XML

<press_limits value="1055" label="Press Limits" type="single 317" format="object">
<projected_area value="0.052944637336319995" label="Projected area of part" type="real(m*m)"/>
<press_tonnage value="500.0" label="Press tonnage" type="real(g)" units="0Ton"/>
<within_press_limit value="1" label="within limits of press" type="boolean"/>
From XML like the above, the XAML below will generate a form that displays the values, with appropriate controls and value formats. But I can't get the stuff converted back. I fail to see a simple change that will meet the requirements of Binding. Perhaps fixing this requires an architecture change. How can I do this differently?
The magic starts here. Bind this ItemsControl to an XmlElement, and it builds a ControlChooser for each subelement.
<ItemsControl ItemsSource="{Binding XPath=*}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate><WrapPanel/></ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<W3V:ControlChooser Content="{Binding}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
The ControlChooser triggers on the format attribute:
<Style.Triggers>
<DataTrigger Binding="{Binding XPath=#format}" Value="spin">
<Setter Property="ContentTemplate" Value="{StaticResource combo}" />
</DataTrigger>
to pick a DataTemplate:
<DataTemplate x:Key="combo" > <W3V:ComboView /> </DataTemplate>
which instatiates the following control:
<ComboBox Style="{StaticResource ComboButtonStyle}" Width="200"
Text="{Binding Path=., ## PROBLEM, BUT HOW TO AVOID?
Converter={StaticResource valueFormattingConverter },
IsEditable="True" />
valueFormattingConverter uses the #units, #type, and #value attributes to produce properly formatted text. The trouble is, this doesn't convert back. I asked here: TextBox ConvertBack event doesn't fire for XML element, and learned that it is impossible for Path=. to be used as '.' is an object but not a dependency property.
So then, I need a way to provide a DependencyProperty for Binding. So ComboView needs to receive an object that has a property which is or has the XmlElement I want. I think this means I really need to change things around but haven't the slightest idea how. Maybe there's an MVVM approach to doing this??? Any insights will be appreciated.
An upcoming issue is a need to validate the data typed in and process the information.

The MVVM method: pull the data out of the XML file, and put it a class which is the ViewModel. Each property in the ViewModel corresponds to an item of data in the XML file. Then use a custom DataTemplate to render the contents of the ViewModel to the screen.
We can extend this to render a list of items. Each item in the list is a ViewModel. A DataTemplate always renders based on the type of the property it is attached to. So you can have a list of objects, and a custom DataTemplate for each item in the list. Of course, all of the items in the list would have to inherit from the same type.
This means you can have a list of items, and each item can render differently depending on the type of data in the XML file. This means that each item in the list can have a custom look and feel with different number of decimal places, colors, etc.
I've used this technique before, and it works well.
Update
For examples, see:
http://www.wpftutorial.net/datatemplates.html
http://www.stackoverflow.com/questions/3400532/display-multiple-types-from-a-single-list-in-a-wpf-listbox.

If I was solving this, I would look at generating C# on the fly. Here is how I would do it:
All XAML compiles to a series of C# commands.
I would set the XAML to format things the way I like it.
I would find the equivalent C# code.
I would then insert the appropriate if/else statements to alter the C# to suit.
Another method that I would try:
Its possible to render custom XAML into an area on the screen.
I would edit the XAML, based on the XML, then display this custom XAML on the screen.
I'd be curious to know if either of these methods work in practice, or if there is a better method that would work.

Windows Phone 8 Font Binding

I'm really stumped on how to go about binding fonts to a textbox. I'd like for my user to be able to choose between 3-4 different fonts. I have something like this right now:
<TextBox x:Name="MyTextBox" AcceptsReturn="True" FontSize="20"
FontFamily="{Binding FontSelection}" />
But I have no clue how the c# should look, and I had no luck googling for it. What is the best way to do this? Do I have to create an observable collection? I've tried adding fonts to the Application.Resources, but it wouldn't let me.
Thanks for any answers!

This FontSelection property has to be single item. You could first try simple valid string (like 'Arial'), it could work. Another approach is FontFamily type as poined out by Romasz.
Also there are Converters available, quite easy to implement. http://channel9.msdn.com/Series/Windows-Phone-8-1-Development-for-Absolute-Beginners/Part-25-Advanced-Binding-with-Value-Converters With this you could save user font selection as simple number for example and convert it to appropriate type with Converter.

WP8 - C# - Getting object value from Telerik RadPickerBox

I am currently having an issue regarding this component.
This is the xaml usage of it in my app:
<telerikPrimitives:RadPickerBox x:Name="box_change" Width="0">
<StackPanel Background="White">
<StackPanel Height="618">
<PasswordBox Name="NewPassword1" Padding="2,8,2,8" Margin="10,0,10,0" Style="{StaticResource PasswordBoxStyle}" />
</StackPanel>
</StackPanel>
</telerikPrimitives:RadPickerBox>
I am currently in need of retrieving, from my C# code, the value "password" of the field "NewPassword1", still I am unable to do that.
I already tried retrieving it with something like this:
box_change.NewPassword1.Password
but, of course, else I wouldn't be asking this question right now, this way doesn't work.
What would you suggest to retrieve the value?
Thanks in advance,
Guido

this.NewPassword1.Password
Glad to help!

Have you considered using Telerik's RadPasswordBox for WP8? It's optimized for passwords with masking characters and other features (and easily provides you with the password):
var userEnteredPassword = myPasswordBox.Password;
That being said, even though your PasswordBox is the child of two StackPanels, you can access the Password box in the same scope via NewPassword1. If you have more complex controls see the control's documentation on how to get the value of a child element.

View / Edit dynamic parameters in a grid

I'm evaluating the possibilities to view and edit parameters in a C#/WPF/MVVM application. I'm currently looking into some custom controls from WPF Woolkit Extended, Telerik, DevExpress and Syncfusion. I see two options, a PropertyGrid or a DataGrid-like control.
The problem: My parameter content is in a collection and PropertyGrids don't seem to like those, they like to be bound to objects with properties. On the other hand my parameters have different value types and that is something the Data Grids do not favor, there the columns always have the same value editor (e.g. Check box, Date picker etc).
Does anybody know a reliable control that supports binding to a collection and individual value editors per row?
Other requirements are hierarchical data representation, validation and a search function.

DataGrid lets you use a DataGridTemplateColumn, where you can specify a template that will be applied to each cell in that column. This template could contain a UserControl that you have defined, which analyzes its DataContext and shows the appropriate control. (This will be quite a bit of work, though, so if there exist out-of-the-box solutions for this, you should use that instead.)

After a while of investigation I found out that all frameworks have the ability to apply individual cell editors in columns.
This is usually done in the column definition. A grid has a Columns collection. Each column can set a CellTemplateSelector which was the key to my initial problem.
Here is a little snippet for the Telerik grid view, but down to the CellTemplateSelector they all behave the same, as far as I can judge. All the vendor of 3rd party UI libs seems to have copied the behviour of the WPF DataGrid, of course.
<telerik:RadGridView x:Name="radGridView"
AutoGenerateColumns="False">
<telerik:RadGridView.Columns>
<telerik:GridViewDataColumn DataMemberBinding="{Binding Name}" Header="Parameter" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding Value}" Header="Value">
<telerik:GridViewDataColumn.CellTemplateSelector>
<telerik:ConditionalDataTemplateSelector>
<telerik:DataTemplateRule Condition="PropertyId < 1">
<DataTemplate>
<TextBox Text="{Binding Value, StringFormat=c}"/>
</DataTemplate>
</telerik:DataTemplateRule>
<telerik:DataTemplateRule Condition="PropertyId > 0">
<DataTemplate>
<CheckBox IsChecked="{Binding Value}" />
</DataTemplate>
</telerik:DataTemplateRule>
</telerik:ConditionalDataTemplateSelector>
</telerik:GridViewDataColumn.CellTemplateSelector>
</telerik:GridViewDataColumn>
</telerik:RadGridView.Columns>
In this example the ItmesSource of the grid is bound to my view model that contains Name, Value and PropertyId properties. Based on the PropertyId a control is selected. The thing I like about the Telerik control is that I don't need code-behind since the ConditionalDataTemplateSelector is available in that framework. Better for MVVM to keep your view clean of code behind, I guess.
UPDATE:
Just received an answer from Syncfusion, they say:
We can load different cell editors in one column. For that we have to Handle dataGrid.Model.QueryCellInfo even and we have to change the CellType based on data. We can't avoid code behind. But this can be achieved using Behaviors.

Can I implement ScrollToHorizontalOffset() functionality in XAML? (for a dynamic list)

Here's the problem: I have a data-bound list of items, basically a way for users to map a request to a response. The response is an xml-based file. I'm letting them queue these up, so I've used a combobox for responses. The responses will include the full path, so they get a bit long. I want the displayed text of the combobox to be right-justified so the user can see the file name. For my static controls, I just use ScrollToHorizontalOffset() when a file is loaded and I'm done. For this dynamic list, I'd like to do it in xaml.
The "somewhat ugly" solution would be to store all the ComboBox objects as they load... then I can call ScrollToHorizontalOffset() directly, but I'd really prefer to do it a cleaner way than that! EDIT: (Actually, this may not be reasonable. A quick look at trying to hack around this issue gets into some really awkward situations trying to map my datasource items to the controls)
I've tried HorizontalContentAlignment, that only impacts the "dropped-down" portion of the ComboBox.
I've also tried to hook other various loading events, but haven't found one that works.

Using an Item template you can decide what will be shown.
You can set tooltip. You can then also use converters to add the dots.
<ComboBox x:Name="ConfigurationComboBox" VerticalContentAlignment="Center" ToolTip="saved configuration" SelectionChanged="ConfigurationComboBox_SelectionChanged">
<ComboBox.ItemTemplate>
<DataTemplate >
<StackPanel>
<TextBlock Text="{Binding}" ToolTip="{Binding Path}"></TextBlock>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
To measure the text, see Measuring text in WPF.