//workflow/com.squareup.workflow1.ui.container/BackStackScreen

BackStackScreen¶

class BackStackScreen<StackedT : Screen>(bottom: StackedT, rest: List<StackedT>) : Screen

Represents an active screen (top), and a set of previously visited screens to which we may return (backStack). By rendering the entire history we allow the UI to do things like maintain cached view state, implement drag-back gestures without waiting for the workflow, etc.

Effectively a list that can never be empty.

UI kits are expected to provide handling for this class by default.

Parameters¶

jvm


bottom	the bottom-most entry in the stack
rest	the rest of the stack, empty by default

Constructors¶


BackStackScreen	[jvm] fun <StackedT : Screen> BackStackScreen(bottom: StackedT, vararg rest: StackedT)Creates a screen with elements listed from the bottom to the top.
BackStackScreen	[jvm] fun <StackedT : Screen> BackStackScreen(bottom: StackedT, rest: List<StackedT>)the bottom-most entry in the stack

Functions¶

Name	Summary
equals	[jvm] Content open operator override fun equals(other: Any?): Boolean
get	[jvm] Content operator fun get(index: Int): StackedT
hashCode	[jvm] Content open override fun hashCode(): Int
map	[jvm] Content fun <R : Screen> map(transform: (StackedT) -> R): BackStackScreen<R>
mapIndexed	[jvm] Content fun <R : Screen> mapIndexed(transform: (index: Int, StackedT) -> R): BackStackScreen<R>
plus	[jvm] Content operator fun plus(other: BackStackScreen<StackedT>?): BackStackScreen<StackedT>
toString	[jvm] Content open override fun toString(): String

Properties¶

Name	Summary
backStack	[jvm] val backStack: List<StackedT>Screens to which we may return.
frames	[jvm] val frames: List<StackedT>
top	[jvm] val top: StackedTThe active screen.