android - volley教學 - volley request json




使用Volley發送帶有JSON數據的POST請求 (6)

JsonObjectRequest實際上接受JSONObject作為body。

這篇博客文章中

final String url = "some/url";
final JSONObject jsonBody = new JSONObject("{\"type\":\"example\"}");

new JsonObjectRequest(url, jsonBody, new Response.Listener<JSONObject>() { ... });

這裡是源代碼和JavaDoc@param jsonRequest ):

/**
 * Creates a new request.
 * @param method the HTTP method to use
 * @param url URL to fetch the JSON from
 * @param jsonRequest A {@link JSONObject} to post with the request. Null is allowed and
 *   indicates no parameters will be posted along with request.
 * @param listener Listener to receive the JSON response
 * @param errorListener Error listener, or null to ignore errors.
 */
public JsonObjectRequest(int method, String url, JSONObject jsonRequest,
        Listener<JSONObject> listener, ErrorListener errorListener) {
    super(method, url, (jsonRequest == null) ? null : jsonRequest.toString(), listener,
                errorListener);
}

我想發送一個新的JsonObjectRequest請求:

  • 我想要接收JSON數據(來自服務器的響應):OK
  • 我想將這個請求的JSON格式的數據發送到服務器

    JsonObjectRequest request = new JsonObjectRequest(
        Request.Method.POST, "myurl.com", null,
        new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject response) {
                //...
            }
        },
        new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                //...
            }
        })
        {
            @Override
            protected Map<String,String> getParams() {
                // something to do here ??
                return params;
            }
    
            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                // something to do here ??
                return params;
            }
        };
    

PS我也在我的項目中使用GSON庫。


您也可以通過重寫JsonObjectRequest類的getBody()方法來發送數據。 如下所示。

    @Override
    public byte[] getBody()
    {

        JSONObject jsonObject = new JSONObject();
        String body = null;
        try
        {
            jsonObject.put("username", "user123");
            jsonObject.put("password", "Pass123");

            body = jsonObject.toString();
        } catch (JSONException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        try
        {
            return body.toString().getBytes("utf-8");
        } catch (UnsupportedEncodingException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }

    final String url = "some/url";

代替:

    final JSONObject jsonBody = "{\"type\":\"example\"}";

您可以使用:

  JSONObject jsonBody = new JSONObject();
    try {
        jsonBody.put("type", "my type");
    } catch (JSONException e) {
        e.printStackTrace();
    }
new JsonObjectRequest(url, jsonBody, new Response.Listener<JSONObject>() { ... });

final Map<String,String> params = new HashMap<String,String>();
        params.put("email", customer.getEmail());
        params.put("password", customer.getPassword());
        String url = Constants.BASE_URL+"login";

doWebRequestPost(url, params);


public void doWebRequestPost(String url, final Map<String,String> json){
        getmDialogListener().showDialog();

    StringRequest post = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
        @Override
        public void onResponse(String response) {
            try {
                getmDialogListener().dismissDialog();
                response....

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Log.d(App.TAG,error.toString());
            getmDialogListener().dismissDialog();

        }
    }){
        @Override
        protected Map<String, String> getParams() throws AuthFailureError {
            Map<String,String> map = json;

            return map;
        }
    };
    App.getInstance().getRequestQueue().add(post);

}

protected Map<String, String> getParams() {
   Map<String, String> params = new HashMap<String, String>();

   JSONObject JObj = new JSONObject();

   try {
           JObj.put("Id","1");
           JObj.put("Name", "abc");

   } catch (Exception e) {
       e.printStackTrace();
   }

   params.put("params", JObj.toString());
   // Map.Entry<String,String>
   Log.d("Parameter", params.toString());
   return params;
}

  • 創建一個RequestQueue類的對象。

    RequestQueue queue = Volley.newRequestQueue(this);
    
  • 用響應和錯誤偵聽器創建一個StringRequest

     StringRequest sr = new StringRequest(Request.Method.POST,"http://api.someservice.com/post/comment", new Response.Listener<String>() {
        @Override
        public void onResponse(String response) {
            mPostCommentResponse.requestCompleted();
        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            mPostCommentResponse.requestEndedWithError(error);
        }
    }){
        @Override
        protected Map<String,String> getParams(){
            Map<String,String> params = new HashMap<String, String>();
            params.put("user",userAccount.getUsername());
            params.put("pass",userAccount.getPassword());
            params.put("comment", Uri.encode(comment));
            params.put("comment_post_ID",String.valueOf(postId));
            params.put("blogId",String.valueOf(blogId));
    
            return params;
        }
    
        @Override
        public Map<String, String> getHeaders() throws AuthFailureError {
            Map<String,String> params = new HashMap<String, String>();
            params.put("Content-Type","application/x-www-form-urlencoded");
            return params;
        }
    };
    
  • 將您的請求添加到RequestQueue

    queue.add(jsObjRequest);
    
  • 創建PostCommentResponseListener接口,以便您可以看到它。 這是異步請求的簡單委託。

    public interface PostCommentResponseListener {
    public void requestStarted();
    public void requestCompleted();
    public void requestEndedWithError(VolleyError error);
    }
    
  • AndroidManifest.xml文件中包含INTERNET權限。

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




android-json