TelerikGrid SelectedItems updated only if SelectedItemsChanged event listening

[Claudio]

Hi, i use a TelerikGrid component and i would like to change the UI on grid selection change, so i have:

<TelerikGrid @ref="Grid" ... />

...

@if (Grid?.SelectedItems.Count() > 0)

{

<span>There are items selected!</span>

}

but the message is never displayed even when i select rows on grid.

I noted who if i bind the event SelectedItemsChanged then the SelectedItems property is updated correctly, and the message is diplayed:

<TelerikGrid @ref="Grid" SelectedItemsChanged="@OnSelectedItemsChanged" ... />

...

@if (Grid?.SelectedItems.Count() > 0)

{

<span>There are items selected!</span>

}

 

Why i need to bind SelectedItemsChanged event even if don't use it?

 

Thanks

 

[Marin Bratanov]

Hello Claudio,

You need to use something like this:

 

<TelerikGrid @bind-SelectedItems="@MySelectedItemsCollection" ... />

@if(MySelectedItemsCollection != null && MySelectedItemsCollection.Any())
{
  <span>something if selected items</span>
}

@code{
  IEnumerable<MyModel> MySelectedItemsCollection {get;set;}  = Enumerable.Empty<MyModel>();
}

 

Here are the key points:

• you must use the view-model data, not component reference for this (you can read more about handling the selectedi items from the grid here and here)
• using two-way binding lets you skip your own handler, the framework will do this for you (you can read more about this here)

This is just how the Blazor framework is designed.

Regards,
Marin Bratanov
Progress Telerik