network: Android 網絡判斷（wifi、3G與其他）

public class NetworkProber {

/**
* 網絡是否可用
*
* @param activity
* @return
*/
public static boolean isNetworkAvailable(Context context) {
ConnectivityManager connectivity = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity == null) {
} else {
NetworkInfo[] info = connectivity.getAllNetworkInfo();
if (info != null) {
for (int i = 0; i < info.length; i++) {
if (info[i].getState() == NetworkInfo.State.CONNECTED) {
return true;
}
}
}
}
return false;
}

/**
* Gps是否打開
*
* @param context
* @return
*/
public static boolean isGpsEnabled(Context context) {
LocationManager locationManager = ((LocationManager) context
.getSystemService(Context.LOCATION_SERVICE));
List accessibleProviders = locationManager.getProviders(true);
return accessibleProviders != null && accessibleProviders.size() > 0;
}

/**
* wifi是否打開
*/
public static boolean isWifiEnabled(Context context) {
ConnectivityManager mgrConn = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
TelephonyManager mgrTel = (TelephonyManager) context
.getSystemService(Context.TELEPHONY_SERVICE);
return ((mgrConn.getActiveNetworkInfo() != null && mgrConn
.getActiveNetworkInfo().getState() == NetworkInfo.State.CONNECTED) || mgrTel
.getNetworkType() == TelephonyManager.NETWORK_TYPE_UMTS);
}

/**
* 判斷當前網絡是否是wifi網絡
* if(activeNetInfo.getType()==ConnectivityManager.TYPE_MOBILE) { //判斷3G網
*
* @param context
* @return boolean
*/
public static boolean isWifi(Context context) {
ConnectivityManager connectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();
if (activeNetInfo != null
&& activeNetInfo.getType() == ConnectivityManager.TYPE_WIFI) {
return true;
}
return false;
}

/**
* 判斷當前網絡是否是3G網絡
*
* @param context
* @return boolean
*/
public static boolean is3G(Context context) {
ConnectivityManager connectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();
if (activeNetInfo != null
&& activeNetInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
return true;
}
return false;
}
}
另外還有兩個方法判斷網絡是否可用：

public static boolean isNetworkAvailable_00(Context context) {
ConnectivityManager cm = ((ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE));
if (cm != null) {
NetworkInfo info = cm.getActiveNetworkInfo();
if (info != null && info.isConnectedOrConnecting()) {
return true;
}
}
return false;
}

public static boolean isNetworkAvailable_01(Context context) {
ConnectivityManager cm = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo network = cm.getActiveNetworkInfo();
if (network != null) {
return network.isAvailable();
}
return false;
}
更加嚴謹的寫法：
public static boolean checkNet(Context context) {

try {
ConnectivityManager connectivity = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity != null) {

NetworkInfo info = connectivity.getActiveNetworkInfo();
if (info != null && info.isConnected()) {

if (info.getState() == NetworkInfo.State.CONNECTED) {
return true;
}
}
}
} catch (Exception e) {
return false;
}
return false;
}