Thank you for using Syncfusion Products.
Currently there is no support for “auto layout”. However we have already considered this as a feature and it will be available in our volume 3 SP1 release. We appreciate your patience until then. For now, as a workaround you can achieve your requirement from the sample by manually setting the width of the Columns when the orientation changes.
For your reference, we have prepared a sample based on this in which we have two columns. First column having the width of 3/4th of the frame and the second column having the width of 1/4th of the frame. When the orientation changes we had reapplied the column width in the ViewDidLayoutSubViews override. You can download the sample from the below location.