WPF Discussion Boards

21-Jul-09 6:57

Hi,
I apologize if this is a n00b question, but Binding in SilverLight 3( well XAML) is making my head hurt...

Ok, I have a UserControl x:Name="Root" with a ItemsControl x:Name="List" that I bind with ItemsSource="{Binding Path=Options}", then I use a DataTemplate which is also a UserControl x:Name="Details", now I need to pass the object that my "Root" control is bound to through to my "Details" control, how would I do that with XAML binding?

An example with classes:
An Invoice has one or more InvoiceLine (List<InvoiceLine>) class instances so I bind the Invoice to my root control, and the InvoiceLine to my ItemsControl and display the Line detail in a user control, but I need to pass the Invoice class instance through to the control that displays the lines...

____________________________________________________________
Be brave little warrior, be VERY brave

Michael Sync23-Jul-09 6:36

Michael Sync

23-Jul-09 6:36

Are your detailed control and listing control in same XAML file?

If yes then you can do that way.

View

<UserControl .....
xmlns:viewmodel="......"
>
<UserControl.DataContext>
<viewmodel:YourViewModel>
</UserControl.DataContext>

<DataGrid
ItemSouce="{Binding YourList}"
SelectedItem="{Binding ActiveYourEntity}"
AutoGeneratedColumns="True"
/>

<StackPanel x:Name="Details">
<StackPanel Orentitation="Horizontal">
<TextBlock Text="Field : " Margin="5" />
<Textbox Text="{Binding ActiveYourEntity.Field}" Margin="5" />
</StackPanel>
</StackPanel>
</UserControl>

ViewModel

class YourViewModel : INotifyPropertyChanged{

private ObserverableCollection<YourEntity> yourlist = new ObserverableCollection<YourEntity>();
public ObserverableCollection<YourEntity> YourList {
get{ return yourlist; }
set {
yourlist = value;
SendPropertyChanged("YourList");
}
}

private YourEntity activeYourEntity = new YourEntity();
public YourEntity ActiveYourEntity {
get{ return activeYourEntity; }
set {
activeYourEntity = value;
SendPropertyChanged("ActiveYourEntity");
}
}

//Do something for implementing INotifyPropertyChanged.
}

Entity

class YourEntity : INotifyPropertyChanged {
private string field = string.Empty;
public string Filed {
get{ return field ; }
set {
field = value;
SendPropertyChanged("Filed");
}
}

//Do something for implementing INotifyPropertyChanged.
}

Thanks and Regards,
Michael Sync ( Blog: http://michaelsync.net)

Microsoft MVP (Silverlight), WPF/Silverlight Insiders

Adriaan Davel23-Jul-09 19:27

23-Jul-09 19:27

Hi Michael,

Thanks for the reply but the answer is no, the UserControl is a seperate XAML file all together... I have managed to work around this by subscribing to the Load event of the child control in the parent control, then using something like ((MyControl)sender).Tag = (Invoice)this.DataContext;, very ugly but seems to work ok'ish...

With the low activity on this thread I'm starting to think that XAML (or SL3) does not allow for this kind of binding, a SERIOUS shortfall in my opinion, this will be a very common requirement in LOB appplications...

____________________________________________________________
Be brave little warrior, be VERY brave

Michael Sync23-Jul-09 20:05

Michael Sync

23-Jul-09 20:05

You can probably use Event Aggregator Pattern or Mediator patten to achieve this. In our project, we are using the Event Aggregator implementation from Prims Framework to deal with this kinda scenero. We used to have MainCRUD.xaml, Listing.xaml and Details.xaml. Listing.xaml and Details.xmal will be shown in MainCRUD.xaml.

There are a few ways to handle it.

Approach #1. MainCRUD will listen the SendPropertyChanged from Listing. If the user select a row, the SelectedEntity property that is binded to the selected item of Datagrid will be triggered the SendPropertyChanged and MainCRUD will get that notification.

Approach #2. use Event Aggregator Pattern or Mediator patten

Hope it helps. Smile | :)

Thanks and Regards,
Michael Sync ( Blog: http://michaelsync.net)

Microsoft MVP (Silverlight), WPF/Silverlight Insiders

Adriaan Davel23-Jul-09 21:21

23-Jul-09 21:21

Hi Micheal,
Thanks for the feedback, I would have to dig into this and play.

____________________________________________________________
Be brave little warrior, be VERY brave

Jeremy Likness26-Jul-09 3:08

Jeremy Likness

26-Jul-09 3:08

I guess I may be missing the boat entirely here, but aren't you doing something like:

<parentcontrol>
<childlistcontrol>
<datatemplate>
<anothercontrolfromsomewhereelse>
</datatemplate>
</childlistcontrol>
</parentcontrol>

If that's the case, binding is hierarchal, right, so you can do this:

<anothercontrolfromsomewhereelse DataContext="{Binding}"/>

And it will inherit the binding from the parent. Is that what you are looking for or did I misunderstand the question?

Jeremy Likness
Latest Article: Hierarchal Data Templates in Silverlight
Blog:
http://csharperimage.jeremylikness.com/

Adriaan Davel27-Jul-09 1:43

27-Jul-09 1:43

Hi Jeremy,

Thanks for the reply, I think this is what I'm after, I'll play with it and let you know

____________________________________________________________
Be brave little warrior, be VERY brave

Global Styles [modified]

#realJSOP21-Jul-09 4:57

21-Jul-09 4:57

I have the following defined in a (merged) resource dictionary:

<Style TargetType="{x:Type TextBox}">
    <Setter Property="BorderBrush" Value="Black" />
    <Setter Property="BorderThickness" Value="1" />
    <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
    <Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
    <Setter Property="Padding" Value="2"/>
    <Setter Property="KeyboardNavigation.TabNavigation" Value="None"/>
    <Setter Property="HorizontalContentAlignment" Value="Left"/>
    <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
    <Setter Property="AllowDrop" Value="true"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type TextBox}">
                <Border x:Name="Bd"
                            CornerRadius="3"
                            Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}">
                    <ScrollViewer x:Name="PART_ContentHost"/>
                </Border>
                <ControlTemplate.Triggers>
                    <Trigger Property="IsEnabled" Value="false">
                        <Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
                        <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
                    </Trigger>
                    <Trigger Property="IsMouseOver" Value="True">
                        <Setter Property="BorderBrush" TargetName="Bd" Value="Purple" />
                    </Trigger>
                    <Trigger Property="IsFocused" Value="True">
                        <Setter Property="BorderBrush" TargetName="Bd" Value="Purple" />
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

If I add a TextBox control to a form, it does not use the global style. Why not?

If I put this style into the form's resources section it works. If I try to use it from it's original location in the resource dictionary, it doesn't.

EDIT ===========================

Why was this 1-voted?

"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001

modified on Tuesday, July 21, 2009 2:33 PM

Pete O'Hanlon21-Jul-09 9:59

21-Jul-09 9:59

John Simmons / outlaw programmer wrote:
Why was this 1-voted?

No idea.

John Simmons / outlaw programmer wrote:
Why not?

Again, no idea. I've just taken your implementation and added it into a dummy application - it works perfectly for me. What I did was add a ResourceDictionary and then pasted your code in. Then, I added the ResourceDictionary into app.xaml like this:

<Application x:Class="ThemeTester.App"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    StartupUri="Window1.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="Dictionary.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

Finally, I added a textbox into a window and it worked perfectly. The only things I can think of are:

1. You haven't merged the resource dictionary in, or
2. You have another style that's being loaded after this one that's overriding the style.

The way to test if it's point 2 is to add this style into a resource dictionary and merge it in as the last style. If it's this problem, the style will start to render properly.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

#realJSOP21-Jul-09 10:18

21-Jul-09 10:18

The way I tried it was to comment out all of the dictionaries that came after the one in question, and it still doesn't work. Does that mean the problem exists in one of the non-dictionary xaml files?

Pete O'Hanlon21-Jul-09 10:24

21-Jul-09 10:24

John Simmons / outlaw programmer wrote:
Does that mean the problem exists in one of the non-dictionary xaml files?

I wouldn't have thought it was the problem, but it's worth having a look.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

#realJSOP21-Jul-09 10:52

21-Jul-09 10:52

No joy in Mudville...

Pete O'Hanlon21-Jul-09 11:31

21-Jul-09 11:31

I've just sent you the code I tried. See how it compares.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

#realJSOP21-Jul-09 23:31

21-Jul-09 23:31

I'm about to look at it, but I wanted to be a sarcastic git first. Smile | :)

I think I've simply put too much code into the application, and have overflowed VS2008's sanity buffer.

Pete O'Hanlon22-Jul-09 0:22

22-Jul-09 0:22

John Simmons / outlaw programmer wrote:
I think I've simply put too much code into the application, and have overflowed VS2008's sanity buffer.

It's a damned shame that they didn't increase the buffer since VS1.

#define SANITY_BUFFER 2048;

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

#realJSOP22-Jul-09 2:21

22-Jul-09 2:21

Here's a new wrinkle for you - when I do this in the textbox element:

Style="{StaticResource {x:Type TextBox}}"

I get the desired results.

Am I correct in assuming that if this works, then my global style is correct and that there is a problem either in the designer or in WPF?

Pete O'Hanlon22-Jul-09 2:23

22-Jul-09 2:23

John Simmons / outlaw programmer wrote:
Am I correct in assuming that if this works, then my global style is correct and that there is a problem either in the designer or in WPF?

It would seem logical. Is it something you could send over to me for me to check out? It would be easier for me to diagnose that way.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

#realJSOP22-Jul-09 2:41

22-Jul-09 2:41

I'm not sure that you would get the same results without getting the entire project, and I'm almost positive the boss wouldn't like it if I shipped off the entire project to someone not in our employ. :/

Pete O'Hanlon22-Jul-09 3:43

22-Jul-09 3:43

It's time for you to snoop then, I'm afraid.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.