The behavior you are describing depends on the configuration of the ComboBox. Generally, the ComboBox makes a request to the server when it needs to load the items. Once the items are loaded, the request to the server is not necessary as the dataSource items are already loaded.
As far as I understand, opening the dropdown in the dataBound
event should fit your case. Here is a Dojo example
representing the described approach.
If it doesn't, would you please provide us more details on the expected behavior and the configuration of the ComboBox. A dojo example or other examples of the desired behavior would be greatly appreciated.
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