Add ActionListener util for global listening

test/listen-to-actions.js

@@ -0,0 +1,45 @@
+import assert from 'assert'
+import Alt from '../dist/alt-with-runtime'
+
+import ActionListeners from '../utils/ActionListeners'
+
+let alt = new Alt()
+
+class MyActions {
+ constructor() {
+ this.generateActions('updateName')
+ }
+}
+
+let myActions = alt.createActions(MyActions)
+
+let listener = new ActionListeners(alt)
+
+export default {
+ 'listen to actions globally'() {
+ let id = listener.addActionListener(myActions.UPDATE_NAME, (name) => {
+ assert.equal(name, 'yes', 'proper data was passed in')
+ })
+
+ assert.equal(typeof id, 'string', 'the dispatcher id is returned for the listener')
+
+ myActions.updateName('yes')
+
+ listener.removeActionListener(id)
+
+ myActions.updateName('no')
+ assert.equal(true, true, 'no error was thrown by above action since listener was removed')
+
+ listener.addActionListener(myActions.UPDATE_NAME, (name) => {
+ assert.equal(name, 'mud', 'proper data was passed in again')
+ })
+
+ myActions.updateName('mud')
+
+ listener.removeAllActionListeners()
+
+ myActions.updateName('bill')
+
+ assert.equal(true, true, 'all listeners were removed')
+ }
+}

utils/ActionListeners.js

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+/**
+ * ActionListeners(alt: AltInstance): ActionListenersInstance
+ *
+ * > Globally listen to individual actions
+ *
+ * If you need to listen to an action but don't want the weight of a store
+ * then this util is what you can use.
+ *
+ * Usage:
+ *
+ * ```js
+ * var actionListener = new ActionListeners(alt);
+ *
+ * actionListener.addActionListener(Action.ACTION_NAME, function (data) {
+ * // do something with data
+ * })
+ * ```
+ */
+module.exports = ActionListeners
+
+var Symbol = require('es-symbol')
+var ALT_LISTENERS = Symbol('global dispatcher listeners')
+
+function ActionListeners(alt) {
+ this.dispatcher = alt.dispatcher
+ this[ALT_LISTENERS] = {}
+}
+
+/*
+ * addActionListener(symAction: symbol, handler: function): number
+ * Adds a listener to a specified action and returns the dispatch token.
+ */
+ActionListeners.prototype.addActionListener = function (symAction, handler) {
+ var id = this.dispatcher.register(function (payload) {
+ symAction === payload.action && handler(payload.data)
+ })
+ this[ALT_LISTENERS][id] = true
+ return id
+}
+
+/*
+ * removeActionListener(id: number): undefined
+ * Removes the specified dispatch registration.
+ */
+ActionListeners.prototype.removeActionListener = function (id) {
+ delete this[ALT_LISTENERS][id]
+ this.dispatcher.unregister(id)
+}
+
+/**
+ * Remove all listeners.
+ */
+ActionListeners.prototype.removeAllActionListeners = function () {
+ Object.keys(this[ALT_LISTENERS]).forEach(
+ this.removeActionListener.bind(this)
+ )
+ this[ALT_LISTENERS] = {}
+}