Group header data is not dynamically changing

[Sandro]

Hi

I have a problem on dynamically change the data on the group data row of RadGridView. Our application has a feature of translating the text into different languages like french, german and etc. We are using observablecollection object and binded to a RadGridview. When we change data to the obsevablecollection (by changing language) , the RadGridview is also reacts to the changes on the observablecollection however the group data row data is not changing. I used the GroupDescriptor of RadGridView.
Can you help me solve this problem?
Thank you in advance

[Maya]

Hi Sandro,

Would you clarify a bit what is the exact scenario that you want to accomplish ? Do you try to localize your RadGridView as in our example ?  Or you want only to update the items written in different language ? Do you change the groups in any way ?
Generally, any relevant information or code-snippet describing your settings would be helpful.

Kind regards,
Maya
the Telerik team

[Sandro]

Here are my example code.

I have a combobox with 2 items. When you change the selected index of the combo, it also change dynamically the child record, however the group record is not changing.

<UserControl x:Class="Sample.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:ViewModels="clr-namespace:Sample.ViewModel"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="400" xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation" xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk">

<UserControl.Resources>
<ViewModels:vmMainPage x:Key="ViewMain" />
</UserControl.Resources>

<Grid x:Name="LayoutRoot" Background="White" DataContext="{Binding Source={StaticResource ViewMain}}">
<telerik:RadGridView Height="232" HorizontalAlignment="Left" Margin="22,43,0,0" Name="RadGridView1" VerticalAlignment="Top" Width="347" ItemsSource="{Binding Path=Products}" AutoGenerateColumns="False" ShowGroupPanel="False">
<telerik:RadGridView.Columns>
<telerik:GridViewDataColumn DataMemberBinding="{Binding Category}" IsVisible="False" Header="Category" IsReadOnly="True" Width="100" MinWidth="100"/>
<telerik:GridViewDataColumn DataMemberBinding="{Binding Name}" Header="Product" IsReadOnly="True" Width="100" MinWidth="100"/>
</telerik:RadGridView.Columns>
<telerik:RadGridView.GroupDescriptors>

<telerik:GroupDescriptor Member="Category" />
</telerik:RadGridView.GroupDescriptors>
</telerik:RadGridView>
<sdk:Label Height="26" HorizontalAlignment="Left" Margin="24,6,0,0" Name="Label1" VerticalAlignment="Top" Width="82" Content="Language" />
<ComboBox SelectedIndex="{Binding SelectedLanguage,Mode=TwoWay}" Height="24" HorizontalAlignment="Left" Margin="102,8,0,0" Name="ComboBox1" VerticalAlignment="Top" Width="164">
<ComboBoxItem Content="English" />
<ComboBoxItem Content="German" />
</ComboBox>
</Grid>
</UserControl>

Imports System.ComponentModel

Imports System.Collections.ObjectModel

Namespace ViewModel

Public Class vmMainPage

Implements INotifyPropertyChanged

Sub New()

_SelectedLanguage = 0

_myProduct = New ObservableCollection(Of clsProduct)

_myProduct.Add(New clsProduct With {.Category = "Category 1", .Name = "Product 1"})

_myProduct.Add(New clsProduct With {.Category = "Category 2", .Name = "Product 2"})

End Sub

Private _myProduct As ObservableCollection(Of clsProduct)

Public Property Products As ObservableCollection(Of clsProduct)

Get

Return _myProduct

End Get

Set(ByVal value As ObservableCollection(Of clsProduct))

_myProduct = value

OnPropertyChanged("Products")

End Set

End Property

Private Sub ChangeLanguage()

If _SelectedLanguage = 0 Then

_myProduct(0).Category = "Category 1"

_myProduct(0).Name = "Product 1"

_myProduct(1).Category = "Category 2"

_myProduct(1).Name = "Product 2"

ElseIf _SelectedLanguage = 1 Then

_myProduct(0).Category = "Kategorie 1"

_myProduct(0).Name = "Produkt 1"

_myProduct(1).Category = "Kategorie 2"

_myProduct(1).Name = "Produkt 2"

End If

End Sub

Private _SelectedLanguage As Integer

Public Property SelectedLanguage As Integer

Get

Return _SelectedLanguage

End Get

Set(ByVal value As Integer)

_SelectedLanguage = value

ChangeLanguage()

OnPropertyChanged("SelectedLanguage")

End Set

End Property

Public Event PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged

Protected Overridable Sub OnPropertyChanged(ByVal propName As String)

RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propName))

End Sub

End Class

End Namespace

Public Class clsProduct

Implements INotifyPropertyChanged

Private _Name As String

Public Property Name As String

Get

Return _Name

End Get

Set(ByVal value As String)

_Name = value

OnPropertyChanged("Name")

End Set

End Property

Private _Category As String

Public Property Category As String

Get

Return _Category

End Get

Set(ByVal value As String)

_Category = value

OnPropertyChanged("Name")

End Set

End Property

Public Event PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged

Protected Overridable Sub OnPropertyChanged(ByVal propName As String)

RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propName))

End Sub

End Class

[Maya]

Hello Sandro,

This would be the expected behavior since the groups will be updated on CollectionChanged event, not on PropertyChanged. Please take a look at this forum thread for a reference on how to invoke CollectionChanged in similar scenario. The thread refers to updating the aggregates, but the idea is the same. 

Best wishes,
Maya
the Telerik team

[Sandro]

Hi

Do you have any simple code just like what I sent?
The sample code from the thread is not easy to understand.

Thank you in advance