android23

来源：http://gundumw100.iteye.com/blog/1051235

/** 判断是否有网络 */  
    private boolean checkNetwork() {  
        boolean flag = false;  
        ConnectivityManager cwjManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);  
        if (cwjManager.getActiveNetworkInfo() != null)  
            flag = cwjManager.getActiveNetworkInfo().isAvailable();  
        if (!flag) {  
            Builder b = new AlertDialog.Builder(this).setTitle("没有可用的网络").setMessage("请开启GPRS或WIFI网络连接");  
            b.setPositiveButton("确定", new DialogInterface.OnClickListener() {  
                public void onClick(DialogInterface dialog, int whichButton) {  
                    Intent mIntent = new Intent("/");  
                    ComponentName comp = new ComponentName("com.android.settings",  
                            "com.android.settings.WirelessSettings");  
                    mIntent.setComponent(comp);  
                    mIntent.setAction("<span class="hilite">android</span>.intent.action.VIEW");  
                    startActivity(mIntent);  
                }  
            }).setNeutralButton("取消", new DialogInterface.OnClickListener() {  
                public void onClick(DialogInterface dialog, int whichButton) {  
                    dialog.cancel();  
                }  
            }).create();  
            b.show();  
        }  
  
        return flag;  
    }  

Android编程获取网络连接状态(3G/Wifi)及调用网络配置界面 
http://www.cnblogs.com/mainroadlee/archive/2011/01/11/Android_Network_State_Checking_And_Setting.html 

Java代码  
/** 
     * 检测是否开启wify或gprs 
     * @param context 
     * @return 
     */  
    public boolean checkNetwork(final Context context){  
        ConnectivityManager manager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);  
  
        //mobile 3G Data Network  
        State mobile = manager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE).getState();  
        //wifi  
        State wifi = manager.getNetworkInfo(ConnectivityManager.TYPE_WIFI).getState();  
          
        //如果3G网络和wifi网络都未连接，且不是处于正在连接状态 则进入Network Setting界面 由用户配置网络连接  
        if(mobile==State.CONNECTED||mobile==State.CONNECTING)  
            return true;  
        if(wifi==State.CONNECTED||wifi==State.CONNECTING)  
            return true;  
          
          
        Builder b = new android.app.AlertDialog.Builder(context).setTitle("没有可用的网络").setMessage("请开启GPRS或WIFI网络连接");  
        b.setPositiveButton("设置网络", new DialogInterface.OnClickListener() {  
            public void onClick(DialogInterface dialog, int whichButton) {  
                context.startActivity(new Intent(Settings.ACTION_WIRELESS_SETTINGS));//进入无线网络配置界面  
//              context.startActivity(new Intent(Settings.ACTION_WIFI_SETTINGS)); //进入手机中的wifi网络设置界面  
            }  
        }).setNeutralButton("取消", new DialogInterface.OnClickListener() {  
            public void onClick(DialogInterface dialog, int whichButton) {  
                dialog.cancel();  
            }  
        }).create();  
        b.show();  
        return false;  
          
    }