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TreeIterables

class TreeIterables

Utility methods for iterating over tree structured items.

Since the view hierarchy is a tree - having a method of iterating over its contents is useful.

This is generalized for any object which can display tree like qualities - but this generalization was done for testability concerns (since creating View hierarchies is a pain).

Only public methods of this utility class are considered public API of the test framework.

Summary

Nested types
TreeIterables.ViewAndDistance

Represents the distance a given view is from the root view.

Public constructors

Public functions
java-static (Mutable)Iterable<View!>!

Returns an iterable which iterates thru the provided view and its children in a breadth-first, row-level-order traversal.
java-static (Mutable)Iterable<View!>!

Returns an iterable which iterates thru the provided view and its children in a depth-first, in-order traversal.
java-static (Mutable)Iterable<TreeIterables.ViewAndDistance!>!

Creates an iterable that traverses the tree formed by the given root.

Public constructors

TreeIterables

TreeIterables()

Public functions

breadthFirstViewTraversal

java-static fun breadthFirstViewTraversal(root: View!): (Mutable)Iterable<View!>!

Returns an iterable which iterates thru the provided view and its children in a breadth-first, row-level-order traversal. That is to say that for a view such as: Root / | \ A R U /| |\ B D G N Will be iterated: Root, A, R, U, B, D, G, N

Parameters
root: View!

the non-null, root view.

depthFirstViewTraversal

java-static fun depthFirstViewTraversal(root: View!): (Mutable)Iterable<View!>!

Returns an iterable which iterates thru the provided view and its children in a depth-first, in-order traversal. That is to say that for a view such as: Root / | \ A R U /| |\ B D G N Will be iterated: Root, A, B, D, R, G, N, U.

Parameters
root: View!

the non-null, root view.

depthFirstViewTraversalWithDistance

java-static fun depthFirstViewTraversalWithDistance(root: View!): (Mutable)Iterable<TreeIterables.ViewAndDistance!>!

Creates an iterable that traverses the tree formed by the given root.

Along with iteration order, the distance from the root element is also tracked.

Parameters
root: View!

the root view to track from.
Returns
(Mutable)Iterable<TreeIterables.ViewAndDistance!>!

An iterable of ViewAndDistance containing the view tree in a depth first order with the distance of a given node from the root.