This flag (in ashinc:xtree.def) will auto-expand the columns to fill the width of the tree control, eliminating the blank space that will otherwise appear when XTR'CLOSEDENDED=1 and the overall tree control is wider than it needs to be for the current data.
define XTF2_AUTOEXPCOL= &h00000010 ! Auto Expand Columns to fill control
The expansion operation increases the width of the visible columns by a uniform percentage rather than by a fixed number of pixels, thus preserving the relative widths. The last column will pick up any extra pixels left over from rounding and if there is no vertical scroll bar.
The flag is ignored in split (XTF2_SPLIT) and open-ended (XTR'CLOSEDENDED=0) controls.
