在Volley上进行GET时，如何发送请求标头为“ Content-Type”：“ application / json”

@Override public Map<String, String> getHeaders() throws AuthFailureError {     Map<String, String> params = new HashMap<String, String>();         params.put("Content-Type", "application/json");    return params; }

在您的实施

public class MainActivity extends AppCompatActivity {    String url = "http://114.35.246.42:2212/MobileApp/DEST_WebService.asmx/GetNews";    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        RequestQueue mQueue = Volley.newRequestQueue(getApplicationContext());        JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(url, jsonBody, new Response.Listener<JSONObject>() {     @Override     public void onResponse(JSonObject response) {         Log.d("TAG", response.toString());     } }, new Response.ErrorListener() {     @Override     public void onErrorResponse(VolleyError error) {         Log.e("TAG", error.getMessage(), error);     } }) { //no semicolon or coma @Override  public Map<String, String> getHeaders() throws AuthFailureError {      Map<String, String> params = new HashMap<String, String>();          params.put("Content-Type", "application/json");     return params;  }         };        mQueue.add(jsonObjectRequest);    }}