Event which is fired when a treegrid row(for the most parent layout) is about to be collapsed. Return false in order to cancel row collapsing. Use args.owner to access the treegrid object. Use args.row to access a row element(for the most parent layout) that should be collapsed(jQuery representation). Use args.fixedRow to access a (top most parent fixed)row element that is going to be collapsed(jQuery representation). If there aren't fixed columns it is undefined. Use args.dataBoundDepth to access the databound level of the topmost treegrid row to be collapsed.
Target Platforms: Windows 8.1, Windows 8.1, Windows 8, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
