Android - 判斷網絡狀態

Android手機同時支持WIFI和3G, 判斷網絡連接, 判斷網絡類型(WIFI或3G).

權限:

判斷網絡連接

    /**
     * 判斷網絡是否可用, 在使用網絡請求是預先使用此方法進行檢查, 以節省資源.
     *
     * @return 可用狀態
     */
    public static boolean isNetAvailable() {
        Context context = App.getAppContext();
        ConnectivityManager manager = (ConnectivityManager)
             context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo info = manager.getActiveNetworkInfo();
        return (info != null && info.isAvailable() && info.isConnected());
    }

判斷網絡類型

ConnectivityManager conMan = (ConnectivityManager) 
    context.getSystemService(Context.CONNECTIVITY_SERVICE);

// 3G
State mobile = conMan.getNetworkInfo(0).getState();

// WIFI
State wifi = conMan.getNetworkInfo(1).getState();

if (mobile == NetworkInfo.State.CONNECTED 
    || mobile == NetworkInfo.State.CONNECTING) {
    // TODO: in mobile do something
} else if (wifi == NetworkInfo.State.CONNECTED 
            || wifi == NetworkInfo.State.CONNECTING) {
    // TODO: in wifi do something
}

更加精細的網絡類型:
TelephonyManager#getNetworkType or NetworkInfo#getSubtypeName