Straight up to your questions:
Currently, the required information is not accessible outside of the widget and hence detecting which tuple member is expanded would be very hard. We will provide a feasible way to get this information via API. Thus you will be able to check whether the member is expanded or not.
For the time being, lets consider this request as unsupported.
I will write a follow-up to this thread once this functionality is available.
Yes, the widget provides a client-side cube engine. It requires the data locally in order to build the cube and bind the grid. You will need to provide the all data you want to categorize locally.
I could not reproduce this (screencast
). Please note that the convertData function is designed to work with expanded column header and wit at least one row tuple. This can be changed by the developer in order to accomplish his business requirements.
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