Method ExpandAllHierarchyItems() expands GridViewRows with property "IsExpandable" at False ?

[TheFlo]

Hello !

I'm using a custom hierarchy on a RadGridView as defined below :

<telerik:RadGridView x:Name="rgvAttributes" AutoGenerateColumns="False" CanUserDeleteRows="False"
                     IsReadOnlyBinding="{Binding IsEditAttributesGrid,Mode=TwoWay}"
                     ItemsSource="{Binding ListEntries}"
                     SelectedItem="{Binding SelectedAttribute, Mode=TwoWay}" SelectionMode="Single">

    <i:Interaction.Behaviors>

        <helper:IsExpandableBehavior IsExpandableSourcePropertyName="IsExpandable" />

    </i:Interaction.Behaviors>

    <telerik:RadGridView.ChildTableDefinitions>

        <telerik:GridViewTableDefinition />

    </telerik:RadGridView.ChildTableDefinitions>

    <telerik:RadGridView.Columns>

        [...]

    </telerik:RadGridView.Columns>

    <telerik:RadGridView.HierarchyChildTemplate>

        <DataTemplate>

            <Control:ContentStepVisualizer />

        </DataTemplate>

    </telerik:RadGridView.HierarchyChildTemplate>

</telerik:RadGridView>

In order to hide the Expand/Collapse Hierarchy button on several rows, I'm using the following method :

1. As the name explains, the simple behavior "IsExpandableBehavior" is used to bind the "IsExpandable" property of each GridViewRow to the corresponding object property of the ObservableCollection<Attribute> ListEntries in my ViewModel,
2. Setting the "IsExpandable" property of one of the Attribute object to False correctly hide the Expand/Collapse Hierarchy button of the corresponding row in the RadGridView.

When calling ExpandAllHierarchyItems() on the RadGridView, every hidden Expand/Collapse Hierarchy buttons appears back and every row expands.

It seems that the ExpandAllHierarchyItems() of RadGridView methods doesn't consider the state of the "IsExpandable" property before expanding a GridViewRow.

Is this the desired behavior or I have done something wrong provoking it ?

Many thanks for your help !

TheFlo

[Dimitrina]

Hi,

 I have tested how the ExpandAllHierarchyItems() overrides the "IsExpandable" property of the GridViewRow. I was not able to reproduce such a behaviour.

Would it be possible for you to send me a simple running project to show what your behaviour do?

All the best,
Didie
the Telerik team

[TheFlo]

Hi Didie,

Thanks for you reply.

I've opened a support ticket (ID 521701) with a full running project attached.
This project shows two RadGridViews :

• One using the Behavior "IsExpandableBehavior" to hide the Expand / Collapse button of the GridViewRow
• One using the event "RowLoaded" to hide the Expand / Collapse button of the GridViewRow using the code given in the Custom Hierarchy Demo example
• Each RadGridView has a button above to Expand / Collapse all rows.
• As I click on each button, the GridViews expand all GridViewRows Hierarchy even those who have the property "IsExpandable" to False.

Hope this project will help.

May thanks for your support,

TheFlo

[Dimitrina]

Hi,

 Indeed I can confirm that this is a bug into the RadGridView. This issue has been logged into our Public Issue Tracking System under ID 9443. 

We apologise for the inconvenience caused. 

Regards,
Didie
the Telerik team

[Aaron]

It is extremely frustrating that this hasn't yet been resolved.

I'm using the following as a workaround:

private void ReportGrid_RowIsExpandedChanging(object sender, Telerik.Windows.Controls.GridView.RowCancelEventArgs e)
{
    // This is a workaround for "ExpandAllHierarchyItems" issue expanding things that shouldn't be expanded.
    GridViewRow row = e.Row as GridViewRow;
    if (row != null && !row.IsExpandable && !row.IsExpanded)
    {
        e.Cancel = true;
    }
}

private void ReportGrid_RowLoaded(object sender, RowLoadedEventArgs e)
{
    // This is a workaround for "ExpandAllHierarchyItems" issue expanding things that shouldn't be expanded.
    GridViewRow row = e.Row as GridViewRow;
    if (row != null && !row.IsExpandable)
    {
        // Force it to re-evaluate the visual state
        Telerik.Windows.Controls.RadGridView grid = sender as Telerik.Windows.Controls.RadGridView;
        grid.CollapseHierarchyItem(row.Item);

        // Force it to re-evaluate the style
        row.IsExpandable = true;
        row.IsExpandable = false;
    }
}

I'm using this in conjunction with a RowStyleSelector that exists in my xaml that sets "IsExpandable" based upon one of my properties