WPF ComboBox Large Data Source MVVM

Question

I have this combobox which is bound to a list of customers with around 5k entries

 <ComboBox  ItemsSource="{Binding Customers}"  Margin="0 0 0 18" 
                       DisplayMemberPath="DisplayMember"
                       SelectedValuePath="Id"
                       SelectedValue="{Binding CustomerId,Mode=OneWay}"
                                 >
                <ComboBox.ItemsPanel>
                    <ItemsPanelTemplate>
                        <VirtualizingStackPanel />
                    </ItemsPanelTemplate>
                </ComboBox.ItemsPanel>
  </ComboBox>

I changed to virtualization and this helped in getting the list faster but when I added SelectedValue to bind to my viewmodel it got very very slow to load.

Is there any way to overcome this problem ?

Regards

You should be using a design that allows the user to search or filter those 5000 down to a more sensible number. Don't use a combobox as a search method and don't make a user scroll more than 2 pages of data. — Andy, Mar 01 '19 at 08:55
Yes you are right. I switched to AutoCompleteText and it did it perfectly, thanks for your comment — user3092984, Mar 01 '19 at 10:33

score 1 · Answer 1 · answered Mar 01 '19 at 07:17

5000 entries in a combobox is quite a burden on the system.

It is also a burden on a user. In general a combobox should not contain more than 10 (debatable) items.

In general I would make the user (or the system) do a pre-selection by adding a filter which decides what items should show in the combobox E.g., all names starting with "A" or, if that set is still too large, all names starting with "Ande".

WPF ComboBox Large Data Source MVVM

1 Answers1