判断网络 获取json展示

==
private String apiurl = “http://120.27.23.105/ad/getAd”;
private ListView listView;
private ArrayList arrayList;

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //找控件
    listView = findViewById(R.id.listView);
    //调用方法
    //接收返回的信息
    boolean netWorkConnected = NetworkUtils.isNetWorkConnected(MainActivity.this);
    if(netWorkConnected) {
        getString1();
    }else{
        Toast.makeText(this, "没网", Toast.LENGTH_SHORT).show();
    }
}
private Handler handler = new Handler(){
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what)
        {
            case 0:
                String json = (String) msg.obj;
                Log.i("xxx",json);
                Gson gson = new Gson();
                JSON fromJson = gson.fromJson(json, JSON.class);

                arrayList = fromJson.getData();
                Toast.makeText(MainActivity.this, arrayList.toString(), Toast.LENGTH_SHORT).show();
                listView.setAdapter(new MyAdapter(arrayList,MainActivity.this));
                break;
        }
    }
};

<---------------------------------------------------------------------->
封装的判断网络的方式
public class NetworkUtils {
//写一个方法传入上下文
public static boolean isNetWorkConnected(Context context){
//获取网络状态’’
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
//得到网路信息
NetworkInfo info = cm.getActiveNetworkInfo();
if (info!=null){
//返回网路状态
return info.isAvailable();
}
return false;
}
}