import View from 'protonic/src/view.js'

public class | source

View

Extends:

Stream → View

A View is a kind of Stream that is useful for transforming the shape of state for use in components or interfaces. A View caches the result of the function, and will only emit state to subscribers if the new return value is distinct from the previous value.

Constructor Summary

Public Constructor
public	constructor(source: Stream, viewFn: function): View constructor - Takes a source stream, and transforms it through a function.

Method Summary

Public Methods
public	destroy() destroy - Clean up subscriptions.

Inherited Summary

From class Stream
public get	state: Immutable: * get state - a getter for returning the current internal state of the Stream.
public set	state(newState: type): type: * set state - a setter that's probably more clever than it needs to be. Instead of setting the internal state, it calls `next`. `stream.next(newState) // is functionally the same as stream.state = newState` Like I said, maybe too clever, but I thinks allow for a more delarative style when writing transformers.
public	forceState(state: Immutable.Map) forceState - called when hydrating state from another source.
public	logStack(name: string, stack: Stack) logStack - Adds a stack to automatically add state changes.
public	next(newState: Immutable) next - Receives new state (externally, ideally through a transformer) and verifies that the new state is different from the Stream's current state before passing on to `sendState` (and, all the observers, by extension).
public	subscribe(observer: function): object subscribe - takes a callback function that is executed any time the stream received new state.

Public Constructors

public constructor(source: Stream, viewFn: function): View source

constructor - Takes a source stream, and transforms it through a function. The view function takes state from the source stream and transforms it into returns a new shape of the state for use in a component or interface.

Override:

Stream#constructor

Params:

Name	Type	Attribute	Description
source	Stream		A stream to receive state from (can be a source stream or a funnel)
viewFn	function		A function that takes state and returns a new shape for the state.