I have a scenario there I need to select multiple items. I use multiple dxSelectBox controls. These controls are bound to CustomDataSource that loads data through REST API.
I have a requirement to exclude already selected items from drop down list options if other selected boxes already contain that item. I apply additional filtering on CustomDataSource loading event to exclude certain IDs.
What I noticed is that dxSelectBox does not request data each time it is expanded. It uses internal cache. This is demo of cache usage:
Expand the list. Toast appears.
Exapand the list second time. No toast means no request was made to datasource.
Question is - how can I force dxSelectBox to ignore its cache and refresh datasource on each dropdown expand?
There is no built-in option to disable this behavior.
As an immediate solution you can define onOpened to manually clear items and load data. For instance, check the following example - https://codepen.io/ArtemDevExpress/pen/ymRYNp?editors=0010
Let us know if this suggestion helps.