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).

If you have WriteOnly property in your Data Item and you set a collection of DataItems as ItemsSource of LocalDataSourceProvider, RadPivotGrid and RadPivotFieldList will not show any data.

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.

Applying "% Difference From" total format to a calculated description formats the calculated data in RadPivotGrid as double, instead of as a percent.

Available with the R3 2016 SP1 release.

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

See the attached image.

Steps to reproduce:
1. I checked the checkboxes 'Product' and 'Price'. The Product field added to row labels, and price to values.
2. Unchecked the 'Price', the price field removed from the pivot.
3. Unchecked the Product, doesn't  remove the products from the pivot.

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;
}

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>();
}

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

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.

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.

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; }
    }//

Setting the Expanded property of the GroupsExpandBehavior assigned to the RowGroupsExpandBehavior property of RadPivotGrid to True, and the RowSubTotalsPosition to None, leads to an error. 

To work this around set the RowSubTotalsPosition to Top. 

Or set the IsExpanded property of the corresponding PivotGroupHeader controls manually.

public MainWindow()
{
InitializeComponent();

// the Opacity is used to avoid the flicker that appears because the groups are rendered just before the collapse logic kicks-in.
this.pivotGrid.Opacity = 0;
this.pivotGrid.Loaded += PivotGrid_Loaded;            
}

private void PivotGrid_Loaded(object sender, RoutedEventArgs e)
{
Dispatcher.BeginInvoke(new Action(() => { 
var headers = this.pivotGrid.ChildrenOfType<PivotGroupHeader>();
foreach (var header in headers)
{
header.IsExpanded = false;
}
this.pivotGrid.Opacity = 1;
}), (DispatcherPriority)3);
}

Add filtering support for the aggregate descriptions (PropertyAggregateDescription).

Currently, there is such feature for the row and column group descriptions.
https://docs.telerik.com/devtools/wpf/controls/radpivotgrid/features/localdatasourceprovider/filtering