The issue targets a Grid with cell selection and DragToSelect feature disabled where at least one column has Visible="false". With this configuration, when using Shift + Click to select multiple cells, the result is a mismatch in the cells that should be selected, after the position where the invisible column is placed.

Video reproduction attached. Reproduction code: https://blazorrepl.telerik.com/GyFuQwPf37H8riAM19.

I discovered "incell" editing mode on the grid, I love it!  It makes the UI very intuitive and quick to update individual fields. It also works great with a PATCH API endpoint.

One minor glitch with "incell editing".  If I click on a cell in a different row, it immediately takes the previous cell out of edit and puts the new cell in edit with a single click -- VERY cool.  But, if you click on a cell in the same row it takes the previous cell out of edit, but doesn't put the new cell in edit mode.  It would be cool if it worked the same as the "clicking in separate rows" functionality. 

Thanks,

Kenny

Consider the following scenario:

<TelerikGrid Data="Animals" Sortable="true">
  <TelerikGridColumns>
    <TelerikGridColumn Field="Color"></TelerikGridColumn>
    <TelerikGridColumn Field="Breed"></TelerikGridColumn>
  </TelerikGridColumns>
</TelerikGrid>

@functions {
  public List<Animal> Animals { get; set; } = new List<Animal> { new Dog { Breed = "Sheepdog", Color = "Black" } };

  public class Animal { public string Color { get; set; } }
  public class Dog : Animal { public string Breed { get; set; } }
}

Everything renders fine for the grid until you attempt to sort by Breed, which results in the following exception:

Not sure what is going on under the hood here, but perhaps this could be fixed by looking at the type of the object, rather than the underlying list?    I'm aware that this can be fixed by changing the data source to List<Dog> , but I think this use case of using a base-class is useful for many dynamic scenarios (think dynamic columns, etc)

Repro steps:

1. Go to https://demos.telerik.com/blazor-ui/grid/editing-inline
2. Click Add
3. Enter some data in all editable fields
4. Click Update
5. Go to the last page

Actual: The "Name" field is blank

Expected: All fields have the appropriate data

Reproducible below, expected results is that after editing the decimal field you'll get the data under the grid. Actual: either it does not get updated, or the value is always 0.

Reproducible

@using Telerik.Blazor
@using Telerik.Blazor.Components.Grid

<TelerikGrid Data=@GridData
             SelectionMode="GridSelectionMode.Multiple"
             @bind-SelectedItems="SelectedItems"
             Pageable="true"
             Height="400px">
    <TelerikGridToolBar>
        <TelerikGridCommandButton Command="MyDelete" OnClick="DeleteSelectedAsync"
                                         Enabled=@(SelectedItems?.Count() > 0) Icon="delete">Delete</TelerikGridCommandButton>
        <TelerikGridCommandButton Enabled="false" OnClick="DeleteSelectedAsync">I must always be disabled</TelerikGridCommandButton>
</TelerikGridToolBar>
    <TelerikGridColumns>
        <TelerikGridCheckboxColumn />
        <TelerikGridColumn Field=@nameof(Employee.Name) />
        <TelerikGridColumn Field=@nameof(Employee.Team) Title="Team" />
    </TelerikGridColumns>
</TelerikGrid>

@result

@if (SelectedItems != null)
{
    <ul>
        @foreach (Employee employee in SelectedItems)
        {
            <li>
                @employee.Name
            </li>
        }
    </ul>
}

@code {
    void DeleteSelectedAsync()
    {
        result = $"On {DateTime.Now} there are {SelectedItems?.Count()} items selected";
    }
    string result;

    public List<Employee> GridData { get; set; }
    public IEnumerable<Employee> SelectedItems { get; set; }

    protected override void OnInitialized()
    {
        GridData = new List<Employee>();
        for (int i = 0; i < 15; i++)
        {
            GridData.Add(new Employee()
            {
                EmployeeId = i,
                Name = "Employee " + i.ToString(),
                Team = "Team " + i % 3
            });
        }

        // select Employee with 3 through 5
        SelectedItems = GridData.Skip(2).Take(3).ToList();
    }

    public class Employee
    {
        public int EmployeeId { get; set; }
        public string Name { get; set; }
        public string Team { get; set; }
    }
}

You can work around this by disabling virtual scrolling with something like this:

ScrollMode="@(Data.Count() > 30 ? GridScrollMode.Virtual : GridScrollMode.Scrollable)"

Simplest repro code is below - expand a few rows and select items in them, or in the parent grid. I would expect that selection in each grid is independent, but the child grid seems to control the parent selection too, even though it is disabled.

<TelerikGrid Data="salesTeamMembers" PageSize="4" Pageable="true" @bind-SelectedItems="@SelectedItemsMainGrid" SelectionMode="@GridSelectionMode.Single">
    <DetailTemplate>
        @{
            var employee = context as MainModel;
            <TelerikGrid Data="employee.Orders" Pageable="true" PageSize="7" SelectionMode="@GridSelectionMode.None">
                <GridColumns>
                    <GridColumn Field="OrderId"></GridColumn>
                    <GridColumn Field="DealSize"></GridColumn>
                </GridColumns>
            </TelerikGrid>
        }
    </DetailTemplate>
    <GridColumns>
        <GridColumn Field="Id"></GridColumn>
        <GridColumn Field="Name"></GridColumn>
    </GridColumns>
</TelerikGrid>

@foreach (var item in SelectedItemsMainGrid)
{
    <div>@item.Name</div>
}

@code {
    List<MainModel> salesTeamMembers { get; set; }
    public IEnumerable<MainModel> SelectedItemsMainGrid { get; set; } = Enumerable.Empty<MainModel>();

    protected override void OnInitialized()
    {
        salesTeamMembers = GenerateData();
    }

    private List<MainModel> GenerateData()
    {
        List<MainModel> data = new List<MainModel>();
        for (int i = 1; i < 16; i++)
        {
            MainModel mdl = new MainModel { Id = i, Name = $"Name {i}" };
            mdl.Orders = Enumerable.Range(1, 15).Select(x => new DetailsModel { OrderId = x, DealSize = x ^ i }).ToList();
            data.Add(mdl);
        }
        return data;
    }

    public class MainModel
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public List<DetailsModel> Orders { get; set; }
    }

    public class DetailsModel
    {
        public int OrderId { get; set; }
        public double DealSize { get; set; }
    }
}

I would like to be able to edit both Date and Time in Grid editing mode.

===

Telerik edit: Possible since version 3.1.0 with through the column EditorType parameter.

Hi there,

currently the grid component does not provide a feature to set a specific position in virtual scrolling mode.

My team has currently implemented a workaround via javascript interop call to set a specific position. The workaround basically calculates the "scroll value" (we reverse engineered this value by looking at the Telerik js code) and passes it to the jQuery scrollTop() function. This results in an update of the scrollbar which in return triggers the OnReadItems event where we fetch the items based on the given skip and take values.

This workaround does not seem to work in all cases and is somewhat unreliable hence i'm requesting an official feature to set a specific position without the javascript hack.

What do you say?

So lonG

Daniel

Reproducible 

Reproducible

Looking through the examples I can't find one with SelectionMode="GridSelectionMode.Multiple" and using a RowTemplate.

ADMIN EDIT: This is not a bug in the component, an example of how this can be implemented by the app is available in the comments.

I'm not sure what I should be binding my checkbox to so it accurately reflects selection state.

From the RowTemplate Example adding SelectionMode:

<TelerikGrid Data=@GridData
             @bind-SelectedItems="@SelectedItems"             
             SelectionMode="GridSelectionMode.Multiple"
             Height="@Height">
    <RowTemplate Context="product">
         @*Trying to inspect what is generated in the examples I came up with this, but not sure what to bind to checked*@
               <td role="gridcell" colspan=0 data-col-index="0">
                    <span>
                        <input class="k-checkbox k-grid-checkbox telerik-blazor" type="checkbox" />
                    </span>
                </td>
         <td>
            <img class="rounded-circle" src="@($"images/{product.ProductId}.jpg")" alt="Alternate Text" />
            @product.ProductName
        </td>
        <td>
            @(String.Format("{0:C2}", product.UnitPrice))
        </td>
    </RowTemplate>
    <GridColumns>
        <GridColumn Field=@nameof(Product.ProductName) Title="Product Name" />
        <GridColumn Field=@nameof(Product.UnitPrice) Title="Unit Price" />
    </GridColumns>
</TelerikGrid>