jiti-meet/react/features/mobile/background/middleware.js

125 lines
3.7 KiB
JavaScript

// @flow
import { AppState } from 'react-native';
import type { Dispatch } from 'redux';
import { APP_WILL_MOUNT, APP_WILL_UNMOUNT } from '../../base/app';
import { MiddlewareRegistry } from '../../base/redux';
import {
_setAppStateListener as _setAppStateListenerA,
_setBackgroundVideoMuted,
appStateChanged
} from './actions';
import {
_SET_APP_STATE_LISTENER,
APP_STATE_CHANGED
} from './actionTypes';
/**
* Middleware that captures App lifetime actions and subscribes to application
* state changes. When the application state changes it will fire the action
* required to mute or unmute the local video in case the application goes to
* the background or comes back from it.
*
* @param {Store} store - The redux store.
* @returns {Function}
* @see {@link https://facebook.github.io/react-native/docs/appstate.html}
*/
MiddlewareRegistry.register(store => next => action => {
switch (action.type) {
case _SET_APP_STATE_LISTENER:
return _setAppStateListenerF(store, next, action);
case APP_STATE_CHANGED:
_appStateChanged(store.dispatch, action.appState);
break;
case APP_WILL_MOUNT: {
const { dispatch } = store;
dispatch(
_setAppStateListenerA(_onAppStateChange.bind(undefined, dispatch)));
break;
}
case APP_WILL_UNMOUNT:
store.dispatch(_setAppStateListenerA(undefined));
break;
}
return next(action);
});
/**
* Handles app state changes. Dispatches the necessary redux actions for the
* local video to be muted when the app goes to the background, and to be
* unmuted when the app comes back.
*
* @param {Dispatch} dispatch - The redux {@code dispatch} function.
* @param {string} appState - The current app state.
* @private
* @returns {void}
*/
function _appStateChanged(dispatch: Function, appState: string) {
let muted;
switch (appState) {
case 'active':
muted = false;
break;
case 'background':
muted = true;
break;
case 'inactive':
default:
// XXX: We purposely don't handle the 'inactive' app state.
return;
}
dispatch(_setBackgroundVideoMuted(muted));
}
/**
* Called by React Native's AppState API to notify that the application state
* has changed. Dispatches the change within the (associated) redux store.
*
* @param {Dispatch} dispatch - The redux {@code dispatch} function.
* @param {string} appState - The current application execution state.
* @private
* @returns {void}
*/
function _onAppStateChange(dispatch: Dispatch<any>, appState: string) {
dispatch(appStateChanged(appState));
}
/**
* Notifies the feature filmstrip that the action
* {@link _SET_IMMERSIVE_LISTENER} is being dispatched within a specific redux
* store.
*
* @param {Store} store - The redux store in which the specified action is being
* dispatched.
* @param {Dispatch} next - The redux dispatch function to dispatch the
* specified action to the specified store.
* @param {Action} action - The redux action {@code _SET_IMMERSIVE_LISTENER}
* which is being dispatched in the specified store.
* @private
* @returns {Object} The value returned by {@code next(action)}.
*/
function _setAppStateListenerF({ getState }, next, action) {
// Remove the old AppState listener and add the new one.
const { appStateListener: oldListener } = getState()['features/background'];
const result = next(action);
const { appStateListener: newListener } = getState()['features/background'];
if (oldListener !== newListener) {
oldListener && AppState.removeEventListener('change', oldListener);
newListener && AppState.addEventListener('change', newListener);
}
return result;
}