Android Volley Post Request - JsonArrayRequest的解决方法

时间:2014-06-23 04:29:38

标签: android android-volley

我知道使用JsonArrayRequest的POST请求不能与Volley一起开箱即用,但我看到这篇帖子here谈到了添加构造函数来处理这个问题。他们的实施是这样的:

public JsonArrayRequest(int method, String url, JSONObject jsonRequest,
        Listener<JSONArray> listener, ErrorListener errorListener) {
    super(method, url, (jsonRequest == null) ? null : jsonRequest.toString(), 
        listener, errorListener);
}

我如何将其添加为构造函数?上述问题提到将其放入Volley工具库中。我将Volley导入为.jar,因此我不确定如何添加这样的构造函数,或者这是否是最好的方法。非常感谢任何帮助。

修改

我已根据建议使用override和constructor创建了以下类。这是班级:

public class PostJsonArrayRequest extends JsonArrayRequest {

    @Override
    protected Map<String, String> getParams() throws AuthFailureError {
        HashMap<String, String> params = new HashMap<String, String>();
        params.put("name", "value");
        return params;
    }

    public PostJsonArrayRequest(int method, String url, JSONObject jsonRequest,
            Listener<JSONArray> listener, ErrorListener errorListener) {
        super(Method.POST, url, null, listener, errorListener);
    }
}

在线路上打电话给我The constructor JsonArrayRequest(int, String, null, Response.Listener<JSONArray>, Response.ErrorListener) is undefined

我该如何纠正?

1 个答案:

答案 0 :(得分:2)

创建一个类并扩展JsonArrayRequest然后覆盖

@Override
protected Map<String, String> getParams() throws AuthFailureError {
    HashMap<String, String> params = new HashMap<String, String>();
    params.put("name", "value");
    return params;
}

并添加一个新的构造函数并在其中调用

super(Method.POST, url, null, listener, errorListener);

或使用此课程

public class PostJsonArrayRequest extends JsonRequest<JSONArray> {

    /**
     * Creates a new request.
     * @param url URL to fetch the JSON from
     * @param listener Listener to receive the JSON response
     * @param errorListener Error listener, or null to ignore errors.
     */
    public PostJsonArrayRequest(String url, Response.Listener<JSONArray> listener, Response.ErrorListener errorListener) {
        super(Method.POST, url, null, listener, errorListener);
    }

    @Override
    protected Map<String, String> getParams() throws AuthFailureError {
        HashMap<String, String> params = new HashMap<String, String>();
        params.put("name", "value");
        return params;
    }

    @Override
    protected Response<JSONArray> parseNetworkResponse(NetworkResponse response) {
        try {
            String jsonString =
                    new String(response.data, HttpHeaderParser.parseCharset(response.headers));
            return Response.success(new JSONArray(jsonString),
                    HttpHeaderParser.parseCacheHeaders(response));
        } catch (UnsupportedEncodingException e) {
            return Response.error(new ParseError(e));
        } catch (JSONException je) {
            return Response.error(new ParseError(je));
        }
    }
}