Android 如何使用3G连接代替Wi-fi？

如何在Android应用程序中使用3G连接而不是Wi-fi？

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我想连接3G连接，有没有连接到3G而不是Wi-fi的示例代码？

只需从另一篇文章复制和粘贴即可

/**
 * Enable mobile connection for a specific address
 * @param context a Context (application or activity)
 * @param address the address to enable
 * @return true for success, else false
 */
private boolean forceMobileConnectionForAddress(Context context, String address) {
    ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    if (null == connectivityManager) {
        Log.debug(TAG_LOG, "ConnectivityManager is null, cannot try to force a mobile connection");
        return false;
    }

    //check if mobile connection is available and connected
    State state = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE_HIPRI).getState();
    Log.debug(TAG_LOG, "TYPE_MOBILE_HIPRI network state: " + state);
    if (0 == state.compareTo(State.CONNECTED) || 0 == state.compareTo(State.CONNECTING)) {
        return true;
    }

    //activate mobile connection in addition to other connection already activated
    int resultInt = connectivityManager.startUsingNetworkFeature(ConnectivityManager.TYPE_MOBILE, "enableHIPRI");
    Log.debug(TAG_LOG, "startUsingNetworkFeature for enableHIPRI result: " + resultInt);

    //-1 means errors
    // 0 means already enabled
    // 1 means enabled
    // other values can be returned, because this method is vendor specific
    if (-1 == resultInt) {
        Log.error(TAG_LOG, "Wrong result of startUsingNetworkFeature, maybe problems");
        return false;
    }
    if (0 == resultInt) {
        Log.debug(TAG_LOG, "No need to perform additional network settings");
        return true;
    }

    //find the host name to route
    String hostName = StringUtil.extractAddressFromUrl(address);
    Log.debug(TAG_LOG, "Source address: " + address);
    Log.debug(TAG_LOG, "Destination host address to route: " + hostName);
    if (TextUtils.isEmpty(hostName)) hostName = address;

    //create a route for the specified address
    int hostAddress = lookupHost(hostName);
    if (-1 == hostAddress) {
        Log.error(TAG_LOG, "Wrong host address transformation, result was -1");
        return false;
    }
    //wait some time needed to connection manager for waking up
    try {
        for (int counter=0; counter<30; counter++) {
            State checkState = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE_HIPRI).getState();
            if (0 == checkState.compareTo(State.CONNECTED))
                break;
            Thread.sleep(1000);
        }
    } catch (InterruptedException e) {
        //nothing to do
    }
    boolean resultBool = connectivityManager.requestRouteToHost(ConnectivityManager.TYPE_MOBILE_HIPRI, hostAddress);
    Log.debug(TAG_LOG, "requestRouteToHost result: " + resultBool);
    if (!resultBool)
        Log.error(TAG_LOG, "Wrong requestRouteToHost result: expected true, but was false");

    return resultBool;
}

/**
*为特定地址启用移动连接
*@param context上下文（应用程序或活动）
*@param address要启用的地址
*@return true表示成功，否则为false
*/
专用布尔forceMobileConnectionForAddress（上下文、字符串地址）{
ConnectivityManager ConnectivityManager=（ConnectivityManager）context.getSystemService（context.CONNECTIVITY_服务）；
if（null==connectivityManager）{
debug（TAG_Log，“ConnectionManager为空，无法尝试强制移动连接”）；
返回false；
}
//检查移动连接是否可用并已连接
State State=connectivityManager.getNetworkInfo（connectivityManager.TYPE_MOBILE_HIPRI.getState（）；
调试（TAG_Log，“TYPE_MOBILE_HIPRI network state:“+state”）；
如果（0==state.compareTo（state.CONNECTED）| | 0==state.compareTo（state.CONNECTING））{
返回true；
}
//除已激活的其他连接外，还激活移动连接
int resultInt=connectivityManager.startUsingNetworkFeature（connectivityManager.TYPE_MOBILE，“enableHIPRI”）；
调试（TAG_Log，“enableHIPRI结果的startUsingNetworkFeature:”+resultInt）；
//-1表示错误
//0表示已启用
//1表示启用
//可以返回其他值，因为此方法是特定于供应商的
如果（-1==resultInt）{
Log.error（TAG_Log，“StartSingNetworkFeature的错误结果，可能是问题”）；
返回false；
}
if（0==resultInt）{
调试（TAG_Log，“无需执行其他网络设置”）；
返回true；
}
//查找要路由的主机名
String hostName=StringUtil.extractAddressFromUrl（地址）；
调试（标记日志，“源地址：”+地址）；
调试（TAG_Log，“路由的目标主机地址：”+主机名）；
如果（TextUtils.isEmpty（hostName））hostName=address；
//为指定的地址创建路由
int hostAddress=lookupHost（主机名）；
如果（-1==主机地址）{
错误（TAG_Log，“错误的主机地址转换，结果为-1”）；
返回false；
}
//等待连接管理器唤醒所需的时间
试一试{
用于（整数计数器=0；计数器0）{
urlToProcess=url.substring（protocolendix+3）；
}否则{
urlToProcess=url；
}
//如果我们在地址中有端口号，我们将删除所有内容
//在端口号之后
int pos=urlToProcess.indexOf（“：”）；
如果（位置>=0）{
urlToProcess=urlToProcess.substring（0，pos）；
}
//如果我们在地址中有资源位置，那么我们将
//“/”之后的一切
pos=urlToProcess.indexOf（'/'）；
如果（位置>=0）{
urlToProcess=urlToProcess.substring（0，pos）；
}
//如果我们有？在地址里然后我们脱光衣服
//“？”之后的一切
pos=urlToProcess.indexOf（'？'）；
如果（位置>=0）{
urlToProcess=urlToProcess.substring（0，pos）；
}
返回urlToProcess；
}
/**
*在{@link ConnectivityManager.requestRouteToHost}使用的int值中转换主机名
*方法
*
*@param主机名
*@return-1如果主机不存在，则在其他位置显示其翻译
*到整数
*/
专用静态int lookupHost（字符串主机名）{
InetAddress InetAddress；
试一试{
inetAddress=inetAddress.getByName（主机名）；
}捕获（未知后异常e）{
返回-1；
}
字节[]加上字节；
国际地址；
addrBytes=inetAddress.getAddress（）；
addr=（（addrBytes[3]&0xff）谢谢…很抱歉重复
/**
 * This method extracts from address the hostname
 * @param url eg. http://some.where.com:8080/sync
 * @return some.where.com
 */
public static String extractAddressFromUrl(String url) {
    String urlToProcess = null;

    //find protocol
    int protocolEndIndex = url.indexOf("://");
    if(protocolEndIndex>0) {
        urlToProcess = url.substring(protocolEndIndex + 3);
    } else {
        urlToProcess = url;
    }

    // If we have port number in the address we strip everything
    // after the port number
    int pos = urlToProcess.indexOf(':');
    if (pos >= 0) {
        urlToProcess = urlToProcess.substring(0, pos);
    }

    // If we have resource location in the address then we strip
    // everything after the '/'
    pos = urlToProcess.indexOf('/');
    if (pos >= 0) {
        urlToProcess = urlToProcess.substring(0, pos);
    }

    // If we have ? in the address then we strip
    // everything after the '?'
    pos = urlToProcess.indexOf('?');
    if (pos >= 0) {
        urlToProcess = urlToProcess.substring(0, pos);
    }
    return urlToProcess;
}

/**
 * Transform host name in int value used by {@link ConnectivityManager.requestRouteToHost}
 * method
 *
 * @param hostname
 * @return -1 if the host doesn't exists, elsewhere its translation
 * to an integer
 */
private static int lookupHost(String hostname) {
    InetAddress inetAddress;
    try {
        inetAddress = InetAddress.getByName(hostname);
    } catch (UnknownHostException e) {
        return -1;
    }
    byte[] addrBytes;
    int addr;
    addrBytes = inetAddress.getAddress();
    addr = ((addrBytes[3] & 0xff) << 24)
            | ((addrBytes[2] & 0xff) << 16)
            | ((addrBytes[1] & 0xff) << 8 )
            |  (addrBytes[0] & 0xff);
    return addr;
}

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />