package Ġdid . chr is . alt . layout Coord ination . view Transitions Ċ Ċ import Ġandroid . support . constraint . Constraint Layout Ċ import Ġandroid . support . constraint . Constraint Set Ċ import Ġandroid . support . v 4 . app . FragmentManager Ċ import Ġdid . chr is . alt . R Ċ import Ġdid . chr is . alt . ui . interfaces . List Scroll Controller ĊĊ Ċ interface ĠView State Transition Ġ{ ĊĊĠĠĠ Ġ// ĠProperties ĊĠĠĠ Ġval Ġconstraint Set : ĠConstraint Set ĊĊĠĠĠ Ġ// ĠFunctions ĊĠĠĠ Ġfun Ġpre Execute ( fragment Manager : ĠFragment Manager , Ġconstraint Layout : ĠConstraint Layout ) Ġ{ ĊĠĠĠĠĠĠĠ Ġval Ġfragment Ġ= Ġ Ġfragment Manager . find Fragment ById ( R . id . frame _ bottom ) ĊĠĠĠĠĠĠĠ Ġ( fragment Ġas ? ĠList Scroll Controller )?. stop List Scroll () ĊĠĠĠ Ġ} ĊĠĠĠ Ġfun Ġpost Execute ( fragment Manager : ĠFragment Manager , Ġconstraint Layout : ĠConstraint Layout ) Ċ } Ċ