RadRating - NumberOfItemsToGenerate property is not working with binding

[catqbat]

Hello,

I'm using RadRating Control for silverlight (2014.1.421.1050). The control is part of my user control and I would like to set number of stars dynamically using binding to dependency property. This however seems not to work - each time the number of stars equals five.

Here are some code snippets:

This is dependency property for my user control, put in code behind:

public partial class my_rating_control : UserControl
{
public my_rating_control()
{
InitializeComponent();

}

public int MaxRating
{
get { return (int)GetValue(MaxRatingProperty); }
set { SetValue(MaxRatingProperty, value); }
}

// Using a DependencyProperty as the backing store for MaxRating.  This enables animation, styling, binding, etc...
public static readonly DependencyProperty MaxRatingProperty =
DependencyProperty.Register("MaxRating", typeof(int), typeof(my_rating_control), new PropertyMetadata(5));

private void UserControl_Loaded(object sender, RoutedEventArgs e)
{
Rating3.NumberOfItemsToGenerate = 7;
}
}

this is xaml for my user control:

<UserControl x:Class="rad_rating_test.my_rating_control"
    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"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400"
    xmlns:telerik="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Input"
             x:Name="UserControl" Loaded="UserControl_Loaded">
    
    <Grid x:Name="LayoutRoot" Background="White">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="Auto" />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>
        <TextBlock Text="Rating set to 7 from xaml" Grid.Row="0" Grid.Column="0" />
        <telerik:RadRating x:Name="Rating1"  Grid.Row="0" HorizontalAlignment="Left" Height="23" Grid.Column="1"  VerticalAlignment="Top"
                             NumberOfItemsToGenerate="7"  />

        <TextBlock Text="Rating set to 7 via binding" Grid.Row="1" Grid.Column="0" />

        <telerik:RadRating x:Name="Rating2" Grid.Row="1" HorizontalAlignment="Left" Height="23" Grid.Column="1"  VerticalAlignment="Top"
                             NumberOfItemsToGenerate="{Binding MaxRating, ElementName=UserControl}"  />

        <TextBlock Text="Rating set to 7 after loaded event" Grid.Row="2" Grid.Column="0" />

        <telerik:RadRating x:Name="Rating3"  Grid.Row="2" HorizontalAlignment="Left" Height="23" Grid.Column="1"  VerticalAlignment="Top"
                            />

    </Grid>
</UserControl>

this is how I use this control in my main page:

<UserControl
    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:local="clr-namespace:rad_rating_test" x:Class="rad_rating_test.MainPage"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400">

<Grid x:Name="LayoutRoot" Background="White">

<local:my_rating_control Margin="0" MaxRating="7"/>

</Grid>
</UserControl>

If you run the application, only the first rating has seven stars: the one which is explicitly set to 7 in xaml: NumberOfItemsToGenerate="7". The rest have 5 stars. 

Could you please tell me how to achieve the desired effect? 

[Martin Ivanov]

Hi Agata,

I can confirm that this is a bug in the RadRating component. I logged it in our feedback portal where you can track its status. I also updated your Telerik points as a small gesture of compensation for the inconvenience caused.

As a workaround you can bind the ItemsSource property of the rating control to the MaxRating property. Then with a converter create a new empty collection with length set to the value of the MaxRating property.

<telerik:RadRating ItemsSource="{Binding MaxRating, RelativeSource={RelativeSource AncestorType=UserControl}, Converter={StaticResource ratingToItemsSourceConverter}}" />
......

public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
    return new object[(int)value];
}

In addition I attached a sample project which demonstrates this approach. 

Regards,
Martin
Telerik

 

 

[catqbat]

Thank you! :)