react-native/Libraries/Network/NetInfo.js

171 lines
4.2 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule NetInfo
* @flow
*/
'use strict';
var NativeModules = require('NativeModules');
var RCTDeviceEventEmitter = require('RCTDeviceEventEmitter');
var RCTReachability = NativeModules.Reachability;
var DEVICE_REACHABILITY_EVENT = 'reachabilityDidChange';
type ChangeEventName = $Enum<{
change: string;
}>;
type ReachabilityStateIOS = $Enum<{
cell: string;
none: string;
unknown: string;
wifi: string;
}>;
/**
* NetInfo exposes info about online/offline status
*
* ### reachabilityIOS
*
* Asyncronously determine if the device is online and on a cellular network.
*
* - `none` - device is offline
* - `wifi` - device is online and connected via wifi, or is the iOS simulator
* - `cell` - device is connected via Edge, 3G, WiMax, or LTE
* - `unknown` - error case and the network status is unknown
*
* ```
* NetInfo.reachabilityIOS.fetch().done((reach) => {
* console.log('Initial: ' + reach);
* });
* function handleFirstReachabilityChange(reach) {
* console.log('First change: ' + reach);
* NetInfo.reachabilityIOS.removeEventListener(
* 'change',
* handleFirstReachabilityChange
* );
* }
* NetInfo.reachabilityIOS.addEventListener(
* 'change',
* handleFirstReachabilityChange
* );
* ```
*
* ### isConnected
*
* Available on all platforms. Asyncronously fetch a boolean to determine
* internet connectivity.
*
* ```
* NetInfo.isConnected.fetch().done((isConnected) => {
* console.log('First, is ' + (isConnected ? 'online' : 'offline'));
* });
* function handleFirstConnectivityChange(isConnected) {
* console.log('Then, is ' + (isConnected ? 'online' : 'offline'));
* NetInfo.isConnected.removeEventListener(
* 'change',
* handleFirstConnectivityChange
* );
* }
* NetInfo.isConnected.addEventListener(
* 'change',
* handleFirstConnectivityChange
* );
* ```
*/
var NetInfo = {};
if (RCTReachability) {
// RCTReachability is exposed, so this is an iOS-like environment and we will
// expose reachabilityIOS
var _reachabilitySubscriptions = {};
NetInfo.reachabilityIOS = {
addEventListener: function (
eventName: ChangeEventName,
handler: Function
): void {
_reachabilitySubscriptions[handler] = RCTDeviceEventEmitter.addListener(
DEVICE_REACHABILITY_EVENT,
(appStateData) => {
handler(appStateData.network_reachability);
}
);
},
removeEventListener: function(
eventName: ChangeEventName,
handler: Function
): void {
if (!_reachabilitySubscriptions[handler]) {
return;
}
_reachabilitySubscriptions[handler].remove();
_reachabilitySubscriptions[handler] = null;
},
fetch: function(): Promise {
return new Promise((resolve, reject) => {
RCTReachability.getCurrentReachability(
function(resp) {
resolve(resp.network_reachability);
},
reject
);
});
},
};
var _isConnectedSubscriptions = {};
var _iosReachabilityIsConnected = function(
reachability: ReachabilityStateIOS
): bool {
return reachability !== 'none' &&
reachability !== 'unknown';
};
NetInfo.isConnected = {
addEventListener: function (
eventName: ChangeEventName,
handler: Function
): void {
_isConnectedSubscriptions[handler] = (reachability) => {
handler(_iosReachabilityIsConnected(reachability));
};
NetInfo.reachabilityIOS.addEventListener(
eventName,
_isConnectedSubscriptions[handler]
);
},
removeEventListener: function(
eventName: ChangeEventName,
handler: Function
): void {
NetInfo.reachabilityIOS.removeEventListener(
eventName,
_isConnectedSubscriptions[handler]
);
},
fetch: function(): Promise {
return NetInfo.reachabilityIOS.fetch().then(
(reachability) => _iosReachabilityIsConnected(reachability)
);
},
};
}
module.exports = NetInfo;