In a Grid loaded with data made of ExpandoObject, set an aggregate GridAggregateType.Sum breaks the grouping feature while GridAggregateType Max, Min and Count work properly
Please find the attached project: in the grid on Index.razor grouping does not work, just comment Index.razor:43 to restore grouping feature
Exception message:
Error: System.InvalidOperationException: No generic method 'Sum' on type 'System.Linq.Enumerable' is compatible with the supplied type arguments and arguments. No type arguments should be provided if the method is non-generic.
at System.Linq.Expressions.Expression.FindMethod(Type type, String methodName, Type[] typeArgs, Expression[] args, BindingFlags flags)
at System.Linq.Expressions.Expression.Call(Type type, String methodName, Type[] typeArguments, Expression[] arguments)
at Telerik.DataSource.Expressions.EnumerableSelectorAggregateFunctionExpressionBuilder.CreateMethodCallExpression(LambdaExpression memberSelectorExpression)
at Telerik.DataSource.Expressions.EnumerableSelectorAggregateFunctionExpressionBuilder.CreateAggregateExpression()
at Telerik.DataSource.EnumerableSelectorAggregateFunction.CreateAggregateExpression(Expression enumerableExpression, Boolean liftMemberAccessToNull)
at Telerik.DataSource.Expressions.GroupDescriptorExpressionBuilder.<ProjectionPropertyValueExpressions>b__39_0(AggregateFunction f)
at System.Linq.Enumerable.SelectIListIterator`2.ToList()
at Telerik.DataSource.Expressions.GroupDescriptorExpressionBuilder.CreateProjectionInitExpression()
at Telerik.DataSource.Expressions.GroupDescriptorExpressionBuilder.CreateAggregateFunctionsProjectionMemberBinding()
at Telerik.DataSource.Expressions.QueryableAggregatesExpressionBuilder.CreateMemberBindings()+MoveNext()
at System.Collections.Generic.LargeArrayBuilder`1.AddRange(IEnumerable`1 items)
at System.Collections.Generic.EnumerableHelpers.ToArray[T](IEnumerable`1 source)
at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
at System.Dynamic.Utils.CollectionExtensions.ToReadOnly[T](IEnumerable`1 enumerable)
at System.Linq.Expressions.Expression.MemberInit(NewExpression newExpression, IEnumerable`1 bindings)
at Telerik.DataSource.Expressions.GroupDescriptorExpressionBuilder.CreateSelectBodyExpression()
at Telerik.DataSource.Expressions.GroupDescriptorExpressionBuilder.CreateSelectExpression()
at Telerik.DataSource.Expressions.GroupDescriptorExpressionBuilderBase.CreateQuery()
at Telerik.DataSource.Extensions.QueryableExtensions.Aggregate(IQueryable source, IEnumerable`1 aggregateFunctions)
at Telerik.DataSource.Extensions.QueryableExtensions.CreateDataSourceResult[TModel,TResult](IQueryable queryable, DataSourceRequest request, Func`2 selector)
at Telerik.DataSource.Extensions.QueryableExtensions.ToDataSourceResult(IQueryable queryable, DataSourceRequest request)
at Telerik.DataSource.Extensions.QueryableExtensions.ToDataSourceResult(IEnumerable enumerable, DataSourceRequest request)
at Telerik.Blazor.Data.TelerikDataSourceBase.ProcessData(IEnumerable data)
at Telerik.Blazor.Components.Common.DataBoundComponent`1.ProcessDataInternal()
at Telerik.Blazor.Components.Common.DataBoundComponent`1.ProcessDataAsync()
at Telerik.Blazor.Components.TelerikGrid`1.DataBoundProcessData()
at Telerik.Blazor.Components.TelerikGrid`1.ProcessDataAsync()
at Telerik.Blazor.Components.TelerikGrid`1.ApplyFiltersAsync()
at Telerik.Blazor.Components.TelerikGrid`1.OnFilterChange(FilterDescriptorBase filter)
at Telerik.Blazor.Components.Common.Filters.TelerikFilterHeader`1.Filter(FilterDescriptor filterDescriptor)
at Telerik.Blazor.Components.Common.Filters.TelerikFilterHeader`1.OnValueChanged(Object newValue)
at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__139_0(Object state)
at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.ExecuteSynchronously(TaskCompletionSource`1 completion, SendOrPostCallback d, Object state)
at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<.cctor>b__23_0(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location where exception was thrown ---
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.ExecuteBackground(WorkItem item)
Hello everyone,
We created this Feature Request to gather feedback on the way the item expansion is working in the Grid state. Currently, you can expand any items with the ExpandedRows collection of int where you pass the indexes of the rows.
Another option, which we are thinking of, is to provide a Collection<Model>. This would let you pass models, instead of indexes and the Grid would automatically expand those items. This approach would make the need to preserve the indexes redundant, which you should currently do when Filtering/Sorting and Grouping the items in the Grid.
We would appreciate your feedback on both approaches and which you think will be easier to use.
<GridCheckboxColumn SelectAll="true" SelectAllMode="GridSelectAllMode.All">
When I apply filtering to the grid and click the SelectAll checkbox in the select column header, the grid selects all the data. I want it to select only the data that the user sees after the filter is applied.
When you change the data source of the grid, it must re-render the data again.
For example, when you use a custom edit form, you add/edit the data with your own code and not through the grid. This is useful, for example, when you only want to show a few columns in the grid, but the model has many more editable fields. Or, when you want a customized layout/behavior of the edit form.
Minimum repro:
@using Telerik.Blazor.Components.Grid@using Telerik.Blazor.Components.Button<TelerikButton OnClick="@ChangeProduct">Works: Change an existing product</TelerikButton><TelerikButton OnClick="@AddProduct">Does not work: Add a new product</TelerikButton><TelerikButton OnClick="@RemoveProduct">Does not work: Remove an existing product</TelerikButton><TelerikGrid Data=@GridData Pageable="true"> <TelerikGridColumns> <TelerikGridColumn Field=@nameof(Product.ProductName) Title="Product Name" /> <TelerikGridColumn Field=@nameof(Product.UnitPrice) Title="Unit Price"> </TelerikGridColumn> </TelerikGridColumns></TelerikGrid>@functions { public List<Product> GridData { get; set; } void AddProduct() { GridData.Insert(0, new Product() { ProductId = DateTime.Now.Millisecond, ProductName = "some product name", UnitPrice = DateTime.Now.Second }); //after updating the data, the grid should show the item at the top of the first page. //at the moment, you need to page, for example, for the data to be updated } protected void ChangeProduct() { GridData.Where(p => p.ProductId == 2).First().ProductName = "changed at " + DateTime.Now; } protected void RemoveProduct() { GridData.RemoveAt(4); //after updating the data, the grid should remove the fourth item immediately //at the moment, you need to page, for example, for the data to be updated } protected override void OnInit() { GridData = new List<Product>(); for (int i = 0; i < 25; i++) { GridData.Add(new Product() { ProductId = i, ProductName = "Product" + i.ToString(), UnitPrice = (decimal)(i * 3.14), }); } } public class Product { public string ProductName { get; set; } public decimal UnitPrice { get; set; } public int ProductId { get; set; } }}
In my particular scenario we have an existing system which is very flexible and has user created entities. We already have the idea of "view definitions" which are used to define how a list of entities (for example companies or contacts) is displayed in a grid format. This view definition contains our own version of sort descriptors to tell us what the initial sorting should be.
I am getting the data using our existing API in the ReadItems method. Because I already have the view definition I can pass our sort descriptor to our API and it returns the data pre-sorted (it also handles paging). I would then like to be able to tell the grid which columns I have sorted by so it could be represented in the UI with the arrow. The grid doesn't actually have to sort the data.
Here is a more detailed description of the case: https://www.telerik.com/forums/grid-questions-07d1fe846889#RgZmmE2avUaSOsIcprdOMg.
Occasionally I am getting TaskCancellation errors such as:
[13:07:52 ERR] Unhandled exception in circuit 'hQsJqY3F4XbTbzQETSggJClg_e4YRyQkrKHFMHCXugM'.
System.Threading.Tasks.TaskCanceledException: A task was canceled.
at Microsoft.JSInterop.JSRuntime.InvokeAsync[TValue](Int64 targetInstanceId, String identifier, Object[] args)
at Microsoft.JSInterop.JSRuntimeExtensions.InvokeVoidAsync(IJSRuntime jsRuntime, String identifier, Object[] args)
at Telerik.Blazor.Components.TelerikComboBox`2.Dispose()
at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__140_0(Object state)
at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.ExecuteSynchronously(TaskCompletionSource`1 completion, SendOrPostCallback d, Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.ExecuteBackground(WorkItem item)
===========
ADMIN EDIT
===========
The error is related to a Microsoft bug. It occurs one minute after some client component has been disposed.
The exceptions are not bypassed due to memory leak. The bug is expected to be fixed in .NET 6 and this will be respected for the Telerik components, so that the errors do not appear.
I want to edit the Excel file the grid exports before it gets to the user. For example, to add a sheet with data I want to generate, or to change columns, formats, colors.
----
ADMIN EDIT
I have attached to this post an example that shows how you can generate your own exported file so you can customize colors, sheets and so on. It also shows how to cache the DataSourceRequest of the grid so you can extract only the current page or all data, and so you can also apply the current grid sorts/filters and so on to the export. This also lets you add metadata to the sheet such as the current user settings such as filters that resulted in this filter.
----
I have a Grid using checkbox selection and when I un-check a row, the SelectedItemsChanged event is not firing. I'm using an async handler.
The problem appears to happen when a row is selected and then un-selected. The event is firing when it is selected but is not firing when it is un-selected.
<TelerikGrid Data="strategicLevelItems" SelectedItems="selectedStrategic" Width="100%" Height="500px"
ScrollMode="GridScrollMode.Scrollable" SelectionMode="GridSelectionMode.Multiple"
SelectedItemsChanged="@((IEnumerable<GetNavigationNodesModel> strategicItems) => OnStrategicSelectAsync(strategicItems))"
FilterMode="GridFilterMode.FilterRow">
<GridColumns>
<GridCheckboxColumn SelectAll="true" Width="40px" OnCellRender="@GridHelpers.CenterAlign" />
<GridColumn Field="@(nameof(GetNavigationNodesModel.Name))" />
</GridColumns>
</TelerikGrid>
private async Task OnStrategicSelectAsync(IEnumerable<GetNavigationNodesModel> selectedItems)
{
selectedStrategic = selectedItems;
var state = tacticalGrid.GetState();
var compositeFilter = new CompositeFilterDescriptor() { LogicalOperator = FilterCompositionLogicalOperator.Or };
foreach (var item in selectedItems)
{
compositeFilter.FilterDescriptors.Add(new FilterDescriptor()
{
Member = "ParentId",
Operator = FilterOperator.IsEqualTo,
Value = item.Id
});
}
state.FilterDescriptors.Clear();
state.FilterDescriptors.Add(compositeFilter);
await tacticalGrid.SetState(state);
}
At the moment, the focus remains on the cell. It should be in the input so the user does not have to perform an extra action (say, click with the mouse) in order to edit data.
This also applies to inserting a new row - the first cell should be focused.
Greetings!
I've been waiting for a few months now to swap to blazor, but one of the things that's currently holding us back is that the filter row can't be used together with the column menu.
I've always found this to be strange, since it's supported in the Angular and MVC versions, which we currently use.
Our users never filter via the column menu, always via the filter row. They hide/lock their columns via the column menu and sometimes sort.
This functionality is thus critical for us.
I can't find any feature request for it, nor any planned roadmap item.
Will this ever be supported because if not, we're gonna have to start looking for alternatives.
Kind regards.
Hi Telerik team,
When I want to bind the Blazor Grid to an ExpandoObject I need to assign the FieldType. I know I have to use non-nullable types.
But I want to use nullable types (for example int?) to have a blank cell within the Grid when there is no value for it. With "typeof(int)" instead of "typeof(int?)" every empty cell shows "0" which I don't want.
Is there any chance to let FieldType accept nullable types?
Best regards,
Rayko
Using mobile browser (Safari iOS or Chrome Android)
Go to demo grid page
https://demos.telerik.com/blazor-ui/grid/overview
Click any grid's filter menu which contains text field
Try to enter text into textbox.
The filter menu automatically closed, so you can't enter anything
---
ADMIN EDIT
this happens because the keyboard pops up, changes the screen size and may even scroll the page, and both of these events hide the popup menu.
A workaround could be using the filter row mode, with the caveat that it takes up more space on the initial rendering, and that filtering happens immediately.
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I need to know which cell the user right clicked on so I can adjust my context menu. I need the cell value, the row model and the field of the column.
---
ADMIN EDIT
The following KB article shows a solution you can use immediately: https://docs.telerik.com/blazor-ui/knowledge-base/grid-which-cell-context-menu.
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