RadGridView: Style cells of auto generated columns

[ffunke]

Hi, 

I am using a RadGridView to bind a DataTable. In that table I have dynamically generated columns. That's why I chose to set AutoGenerateColumns=true. 

I am now looking for a way to style the cells in depending on the properties of the object within the cell of the DataTable.

What I tried until now:

• I tried using a style selector as described here: https://www.telerik.com/forums/cell-style-based-on-cell-value-with-autogeneratecolumns-true. I set the style selector in OnAutoGeneratingColumn. Rest of the solution is as in the examples application. But unfortunatly the converter I wrote does not get an item of my type, but a type DataRowView.
• I tried this solution as well: https://www.telerik.com/forums/radgridview-celltemplate-on-dynamic-columns#3678858. More or less with the same result. I only have a DataRowView in the DataTemplate to bind.

The first method seem the most promissing to me, so here is some code for that:

<UserControl.Resources>
        <Style x:Key="PilotStyle"
               TargetType="telerik:GridViewCell">
            <Setter Property="Background"
                    Value="Magenta" />
        </Style>
        <Style x:Key="ExpansionStyle"
               TargetType="telerik:GridViewCell">
            <Setter Property="Background"
                    Value="Aqua" />
        </Style>
        <valueConverters:RodTimeTypeConverter x:Key="converter" />
        <local:RodTableCellStyleSelector x:Key="selector"
                                         ConditionConverter="{StaticResource converter}">
            <local:RodTableCellStyleSelector.Rules>
                <local:ConditionalStyleRule Style="{StaticResource PilotStyle}">
                    <local:ConditionalStyleRule.Value>
                        <system:Boolean>True</system:Boolean>
                    </local:ConditionalStyleRule.Value>
                </local:ConditionalStyleRule>
                <local:ConditionalStyleRule Style="{StaticResource ExpansionStyle}">
                    <local:ConditionalStyleRule.Value>
                        <system:Boolean>False</system:Boolean>
                    </local:ConditionalStyleRule.Value>
                </local:ConditionalStyleRule>
            </local:RodTableCellStyleSelector.Rules>
        </local:RodTableCellStyleSelector>
    </UserControl.Resources>

<telerik:RadGridView  Grid.Row="1"
                                  CanUserSortColumns="False"
                                  CanUserSelectColumns="False"
                                  CanUserReorderColumns="False"
                                  CanUserDeleteRows="False"
                                  CanUserGroupColumns="False"
                                  CanUserSelect="False"
                                  IsFilteringAllowed="False"
                                  ShowColumnSortIndexes="False"
                                  ShowGroupPanel="False"
                                  RowHeight="45"
                                  AutoGeneratingColumn="GridViewDataControl_OnAutoGeneratingColumn"
                                  ItemsSource="{Binding RodTimesTable.DefaultView}">
                <telerik:RadGridView.Resources>
                    <Style TargetType="{x:Type TextBlock}">
                        <Setter Property="FontSize"
                                Value="20" />
                    </Style>

                </telerik:RadGridView.Resources>
            </telerik:RadGridView>

public class RodTableCellStyleSelector : StyleSelector
    {
        public override Style SelectStyle(object item, DependencyObject container)
        {
            var conditionValue = this.ConditionConverter.Convert(item, null, null, null);
            foreach (var rule in this.Rules.Where(rule => Equals(rule.Value, conditionValue)))
            {
                return rule.Style;
            }

            return base.SelectStyle(item, container);
        }

        List<ConditionalStyleRule> rules;
        public List<ConditionalStyleRule> Rules
        {
            get
            {
                return this.rules ??= new List<ConditionalStyleRule>();
            }
        }

        public IValueConverter ConditionConverter { get; set; }
    }
    public class ConditionalStyleRule
    {
        public object Value { get; set; }

        public Style Style { get; set; }
    }

private void GridViewDataControl_OnAutoGeneratingColumn(object sender, GridViewAutoGeneratingColumnEventArgs e)
        {
            var grid = (RadGridView)sender;
            var dataGrid = (grid.ItemsSource as DataView)?.Table;
            e.Column.Header = dataGrid?.Columns[e.Column.Header.ToString()].Caption;
            if (e.Column.Header != null && (e.Column.Header.ToString().StartsWith("Pilot") || e.Column.Header.ToString().StartsWith("Expansion")) )
            {
                e.Column.CellStyleSelector = (StyleSelector)this.FindResource("selector");
            }
        }

I would really appreciate any help.

 

Thanks in advance.

[Stenly]

Hello Ferdinand,

The item parameter will be of type DataRowView as you have noticed. Through its Row property, you could retrieve the DataRow instance, which exposes the ItemsArray collection. This collection will provide information about the row's cells' values. 

The following code snippet shows the above suggestion's implementation:

public override Style SelectStyle(object item, DependencyObject container)
{
    DataRowView dataRowView = (DataRowView)item;
    DataRow dataRow = dataRowView.Row;
    object?[] items = dataRow.ItemArray;

    //Find the needed value and return the desired Style property
}

With this being said, I have prepared a sample project for you to test.

Regards,
Stenly
Progress Telerik

[ffunke]

That did the trick. Thanks a lot.