If no chain style is configured, the ConstraintLayout will default to the spread chain style. The chain style can be altered by right-clicking any of the widgets in the chain and selecting the Cycle Chain Mode menu option. Each time the menu option is clicked the style will switch to another setting in the order of spread, spread inside and packed.
Alternatively, the style may be specified in the Attributes tool window unfolding the layout_constraints property and changing either the horizontal_chainStyle or vertical_chainStyle property depending on the orientation of the chain:
Figure 20-3
