Currently the header of that column says "Grand Total" instead of the aggregate name.

Add average/min/max built in functions for DateTime and TimeSpan values

Currently, RadPivotGrid supports UI-based selection, which highlights the selected cells. However, the API that handles this is internal and it cannot be used to manually access the selection. Add API that allows to get the selected items and to update the selection.

Currently, the string format (used in the cells generated for the  from the DateTimeGroupDescription) is determined automatically based on the selected Step (Day, Month, etc.). Add an option to easily set custom string format.

At this moment, you can change the format only if you create a custom description and override a considerable amount of code. This is shown in the following SDK example: https://github.com/telerik/xaml-sdk/tree/master/PivotGrid/CustomDateTimeGroupDescription

 

Currently, changing the visibility of the Expand/Collapse icon, via style, will apply it to all of the elements which are of type PivotGroupHeader.  

Currently, the dates in the filter dialogs of RadPivotList are using invariant culture format. Allow the format to respect the currently applied application or data provider culture.

Currently the LocalDataSourceProvider has such support and we can consider introducing the same functionality in the QueryableDataProvider.

All of the functionalities inside the column headers are located in the RadPivotFieldList. Add the same behavior in the RadPivotGrid.

I implemented it for me, but I will be glad to get it out of the box for all providers.

public class ExtendableLocalDataSourceFieldDescriptionsProvider : LocalDataSourceFieldDescriptionsProvider
{
    protected override ContainerNode GetFieldDescriptionHierarchy(IEnumerable<IPivotFieldInfo> fieldInfos)
    {
        var root = base.GetFieldDescriptionHierarchy(fieldInfos);
        var childs = from node in root.Children
                        let info = node.GetFieldInfoNode()
                        let dispAtt = info.FieldInfo.GetDisplayAttribute()
                        let groupName = dispAtt.GetGroupName()
                        where !string.IsNullOrEmpty(groupName)
                        group node by groupName into g
                        select new
                        {
                            g.Key,
                            g
                        };

        foreach (var group in childs.Reverse())
        {
            var newFolder = new ContainerNode(group.Key, ContainerNodeRole.Folder);
            foreach (var item in group.g)
            {
                root.Children.Remove(item);
                newFolder.Children.Add(item);
            }
        }
        return root;
    }

Note: GetFieldInfoNode & GetDisplayAttribute are extension methods.

The implemented is very easily:

public class ExtendableLocalDataSourceFieldDescriptionsProvider : LocalDataSourceFieldDescriptionsProvider
{
    protected override ContainerNode GetFieldDescriptionHierarchy(IEnumerable<IPivotFieldInfo> fieldInfos)
    {
        var infos = from info in fieldInfos
                    orderby info.GetDisplayAttribute()?.GetOrder()
                    select info;
        return base.GetFieldDescriptionHierarchy(fieldInfos);
}

We will be glad to get it out of the box for all data providers.

When I use QueryableDataProvider, the DisplayName of the aggregates is "Sum of MyField" etc., instead of the value of 'Pivot_AggregateSum' localization key.

As you did with PropertyInfoFieldInfo, which expose PropertyInfo property.

This can be very helpful to many custom logic based on the source PropertyInfo.
For example:

private static DisplayAttribute GetDisplayAttribute(QueryableFieldDescription fieldInfo)
{
    return fieldInfo.PropertyInfo.GetCustomAttribute<DisplayAttribute>();
}

With the current implementation the top level header only visually appears as one cell, however it stretches the subheader column below (check PivotGrid(Now).png).


Looking the attach file,now the XAML is following:
<pivot:LocalDataSourceProvider.AggregateDescriptions>
                        <pivot:PropertyAggregateDescription PropertyName="AccValue" CustomName="total"/>
                        <pivot:PropertyAggregateDescription PropertyName="IncValue" CustomName="increased"/>
                 </pivot:LocalDataSourceProvider.AggregateDescriptions>

 <pivot:LocalDataSourceProvider.ColumnGroupDescriptions>
                        <pivot:PropertyGroupDescription PropertyName="SystemDeviceCode"/>
                    </pivot:LocalDataSourceProvider.ColumnGroupDescriptions>
the SystemDeviceCode column just use one column ,like the attach "PivotGrid(Now).png",when the text is long ,the first column "Total" is too wide .
I hope like the attach "PivotGrid(desired).PNG",the SystemDeviceCode column can span two columns.
     and the data struct:

 public class DayStruct1
    {
        public string HourNum { get; set; }
        public string SystemDeviceCode { get; set; }
        public double AccValue { get; set; }
        public double IncValue { get; set; }
        public DateTime Date { get; set; }
    }//

I have Written behavior to auto-format the AggregateDescription.StringFormat.

Now, I need to list all possible AggregateDescription's, with reference to their DLL.
if (e.Description is LocalAggregateDescription)
{
    (e.Description as LocalAggregateDescription).StringFormat = MyStringFormat;
}
else if (e.Description is QueryableAggregateDescription)
{
    (e.Description as QueryableAggregateDescription).StringFormat = MyStringFormat;
}
else if (e.Description is Other_XYZ_AggregateDescription)
{
    (e.Description as Other_XYZ_AggregateDescription).StringFormat = MyStringFormat;
}

But, if IStringFormattableAggregate was public, I would can write it better:
if (e.Description is IStringFormattableAggregate)
{
    (e.Description as IStringFormattableAggregate).StringFormat = MyStringFormat;
}

Currently, you can use the FilterDescriptions of the Olap data providers (like AdomdDataProvider and XamlDataProvider) or the GroupFilter of the group descriptions. 

Add an API that allows you to implement custom filtering behavior using a filtering function or constructing custom filtering expression.

It happens when you change the distinct values selection several times. The PivotGrid disappears after the exception is thrown.
I managed to reproduce it in the demo by repeating this action around ten times.

When a filter dialog is shown (Report Filter or Label Filter) for OLAP Hierarchy, it contains the items only for the selected level. Instead items from all levels could be visible, so you won't have to open additional dialogs to filter them (show them like a tree).

Last row groups and totals are cut off when the FieldListBehavior.ShowInline attached property is set to True on the RadPivotGrid and there is a vertical scrollbar present.

Users should be able to navigate through the elements of RadPivotGrid using a keyboards. For example, moving between cells, collapsing headers with space, etc.