Hierarchy Child Grid Expand/Collapse issue

[Arman]

Hi telerik team,

I notice one issue related with hierarchy child grid. In my simple project I have telerik grid control and also child grids for each row (set via hierarchy child template property). Steps to see the issue.

Steps:
1. Expand all rows from the beginning of the main grid (step1.jpg).
2. Start collapsing of the rows started from the last one (3 rows are enough) (step2.png)
3. Scroll up to the first row of the main grid (step3.png)

You will see empty space on the top of the main grid (step3.png).
Please tell mi how can I resolve this issue.

Here is the code:

XAML:

<UserControl x:Class="Hierarchy_Child.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"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400"
    xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
    xmlns:data="clr-namespace:Hierarchy_Child">
    <UserControl.Resources>
        <data:Data x:Key="Source" />
    </UserControl.Resources>

    <Grid x:Name="LayoutRoot" Background="White">
        <telerik:RadGridView DataContext="{StaticResource Source}"
                             ItemsSource="{Binding Requirements}"
                             AutoGenerateColumns="False"
                             >
            <telerik:RadGridView.Columns>
                <telerik:GridViewDataColumn DataMemberBinding="{Binding F1}"  />
                <telerik:GridViewDataColumn DataMemberBinding="{Binding F2}" />
            </telerik:RadGridView.Columns>
            <telerik:RadGridView.ChildTableDefinitions>
                <telerik:GridViewTableDefinition />
            </telerik:RadGridView.ChildTableDefinitions>
            <telerik:RadGridView.HierarchyChildTemplate>
                <DataTemplate>
                    <telerik:RadGridView
                             ItemsSource="{Binding RequirementsChild}"
                             HorizontalAlignment="Left"
                             Margin="25 0 0 0"
                             AutoGenerateColumns="False"
                             >
                        <telerik:RadGridView.Columns>
                            <telerik:GridViewDataColumn DataMemberBinding="{Binding F3}" />
                            <telerik:GridViewDataColumn DataMemberBinding="{Binding F4}" />
                        </telerik:RadGridView.Columns>
                    </telerik:RadGridView>
                </DataTemplate>
            </telerik:RadGridView.HierarchyChildTemplate>
        </telerik:RadGridView>
    </Grid>
</UserControl>

C#:

public class RequirementModel
    {
        public int F1 { get; set; }

        public int F2 { get; set; }

        public List<RequirementChildModel> RequirementsChild { get; set; }
    }

    public class RequirementChildModel
    {
        public int F3 { get; set; }

        public int F4 { get; set; }
    }

    public class Data
    {
        public List<RequirementModel> Requirements { get; set; }

        public Data()
        {
            Requirements = new List<RequirementModel>();
            for (int i = 0; i < 10; i++)
            {
                RequirementModel rm = new RequirementModel();
                rm.F1 = 13;
                rm.F2 = 15;
                rm.RequirementsChild = new List<RequirementChildModel>();
                for (int j = 0; j < 4; ++j)
                {
                    rm.RequirementsChild.Add(new RequirementChildModel() { F3 = 17, F4 = 90 });
                }
                Requirements.Add(rm);
            }
        }
    }

Thanks,
Arman.

[Yordanka]

Hello Arman,

Can you set RadGridView.GroupRenderMode="Flat" and let me know if the problem still occurs?
 
Regards,
Yordanka
Telerik

[Arman]

Hello Yordanka,

I added GroupRenderMode="Flat" to the main grid.
Now everything is working fine.

Thanks a lot.
Arman.

[Krithiga]

Hi

 

I am using Hierarchical RadGridView , I need to auto expand all the child grid while loading the parent grid , Instead of clicking the Expand Button, Please let me know how I can achieve this

[Stefan]

Hi Krithiga,

For achieving this, you can use the built-in ExpandAllHierarchyItems() method of RadGridView. Can you please give it a try and let me know how it goes?

Regards,
Stefan X1
Telerik