RadzenListBox bug

Radzen.Blazor Components
1

Hello Radzen Team!

There is a bug in the RadzenListBox component, when using these properties:

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For example let's say I have all items checked:
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Then as soon as I try filtering, the group checkbox becomes unchecked:
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To me that's unexpected behavior, since the group checkbox when being defined should consider either the original data source, or the filtered data. In my example, both datas have all their items selected.

Now the bug escalates to some other problems, after I select the group checkbox:
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Then after removing the filter, the unfiltered items become unchecked for some reason:
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This is a tough one, because does checking all the filtered items imply in deselecting the unfiltered items? Personally I don't think that should be the case, as it may confuse the user quite a bit.

From this point on, if I try filtering for the unchecked items, this is the result:
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2

Hi @kim,

Yes, this is how we decided to implement the select all checkbox in the ListBox and DropDown components. Basically this checkbox is checked when the selected item count is equal to the visible (filtered) item count. So when you filter and reduce the visible item count it unchecks.

We just had a one hour long discussion with @enchev and couldn't find the best way to address your comments. We also checked four other vendors only to find four different implementations that all had their own inconsistencies :slight_smile: The closest thing to a "reference" implementation that we know of is Windows Explorer. It however completely clears the selection during filtering which defeats the whole purpose of filtering.

In the past this checkbox behaved in a different way - it was checked only when the user checked it. Filtering didn't update its state. Unchecking a specific item also didn't update its state. People complained that this was inconsistent so we implemented it the way it is now.

3

I see, it is indeed a very complicated component. Maybe it will never fit to everyone's needs, as each user expects different outcomes. Even tough it will not be possible to fix this, I gladly thank you and @enchev for your time.