7. Network_0

Android Network API
Apache Http Component library
In org.apache.http.* a toolset of low level Java components focused on HTTP and associated protocols.
Berkley socket
How to manage connections?
Scenario:
Phone has Wi-Fi & 3G connections simultaneously User go outside the Wi-Fi area A network connection is available now Application want to route via specific network interface
We need a system module to manage this on Mobile phones
Android use Connectivity Manager
Connectivity Manager
.ConnectivityManager
1. Monitor network connections (Wi-Fi, GPRS, UMTS, etc.) 2. Send broadcast intents when network connectivity changes 3. Attempt to "fail over" to another network when connectivity to a network is lost 4. Provide an API that allows applications to query the coarse-grained or fine-grained state of the available networks
RIL Overview
Android Webview
Dial/Answer phone, Send/Receive SMS (Cellular) Speakers Switch: Ringtone / Bluetooth Earphone(Multimedia System) GPRS/3G Navigation (Network System) Cell Tower Location (Location System) Video Conference (Camera System) Control / Networking on same port (Virtual Device Driver)
List<ScanResult> wifiList; WifiManager wm; WifiReceiver receiverWifi; class WifiReceiver extends BroadcastReceiver { public void onReceive(Context c, Intent intent) { StringBuilder sb = new StringBuilder(); wifiList = wm.getScanResults(); for(int i = 0; i < wifiList.size(); i++){ sb.append(new Integer(i+1).toString() + "."); sb.append((wifiList.get(i)).toString()); sb.append("\n"); } Log.e("WIFI", sb.toString()); } } public void onClick(View v) { registerReceiver(receiverWifi, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)); wm = (WifiManager)getSystemService(Context.WIFI_SERVICE); wm.startScan(); }
More integrated way
/ajax/services/search/web?&a googleService = http:// try { url = new URL(googleService); connection = url.openConnection(); String line; StringBuilder builder = new StringBuilder() BufferedReader reader = new BufferedReader(new InputStreamReader( connection.getInputStream())); while ((line = reader.readLine()) != null) { builder.append(line); } json = new JSONObject(builder.toString()); } catch (Exception e) { e.printStackTrace(); }
Check background data status
ConnectivityManager.getBackgroundDataSetting
Broadcast Receiver of networks status change
ConnectivityManager.CONNECTIVITY_ACTION
Implemented as Android Service. Lightweight
Do not require Pair / Connect or Addressing
Android Telephony
Phone = PC + Cellular
Phone Features:
7. Networking
何宗键 hezongjian@
Agenda
Android Network Overview and Management
Socket and HTTP
Wi-Fi and Bluetooth
Cellular Network and Telephony
Java Networking API
String urltext = ""; URL url; String inputLine; try { url = new URL(urltext); BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream())); while ((inputLine = in.readLine()) != null) { Log.v("TTT", inputLine); } in.close(); } catch (Exception e) { e.printStackTrace(); }
Short Message Service
Android Network Overview
Connect using peripherals
Wireless LAN Bluetooth USB bridge to PC
Self-owned network
Cellular Network
Wi-Fi Management
Android provide .wifi package to manage wifi connection, including:
Search Authentication Connection / Disconnection Status Status change notification ……
Why HTTP
REST API everL-RPC)/ Weibo API
RSS
…..
Demo: Search Google in Android
With Intent
Intent intent = new Intent(); intent.setAction(Intent.ACTION_WEB_SEARCH); intent.putExtra(SearchManager.QUERY,"张三"); startActivity(intent);
if (null == info) { Log.e("NETWORK", "No network"); } Log.e("NETWORK", String.valueOf(info.isConnected()));
// Press F8 to connect / disconnect network in emulator
Share network to other devices
Wi-Fi Tethering …
Advantage to Application
Always online
Programmer can assume connectivity present
Integrated APIs
Java Networking API
In .* Basic features
Apache HTTP library
HttpClient client = new DefaultHttpClient(); HttpPost post = new HttpPost(""); try { HttpResponse response = client.execute(post); BufferedReader rd = new BufferedReader(new InputStreamReader( response.getEntity().getContent())); String line = ""; while ((line = rd.readLine()) != null) { Log.e("HTTP", line); } } catch (IOException e) { e.printStackTrace(); }