Question

我正在使用volley来接收来自数据源的数据，如果我在查询上执行某些操作（例如添加参数它不起作用），那么问题就在于回收器视图。 Volley有任何问题吗？

public void getting locations() {
    String url = "URL REMOVED";
    RequestQueue queue = Volley.newRequestQueue(MainActivity.this); // this = context
    JsonObjectRequest jsonObjReq = new JsonObjectRequest(
            Request.Method.GET, url, null,
            new Response.Listener<JSONObject>() {
                @Override
                public void onResponse(JSONObject response) {
                    JSONObject status = null;
                    try {
                        JSONObject jObj = new JSONObject(String.valueOf(response));

                        JSONArray jr = jObj.getJSONArray("products");
                        for(int i=0;i<jr.length();i++)
                        {
                            JSONObject jb1 = jr.getJSONObject(i);
                            String title = jb1.getString("title");
                            Log.d("Title",""+title);
                            String img = jb1.getString("featured_src");
                            JSONArray a = jb1.getJSONArray("categories");
                            String category = "";

                            lstBook.add(new Book(title,"rAJA","Description book",img));

                        }




                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        }, new Response.ErrorListener() {

    @Override
    public void onErrorResponse(VolleyError error) {
        VolleyLog.d("EROOOOOOOOOOOOOOOOOOOOOR", "Error: " + error.getMessage());
    }
}) {
    @Override
    public Map<String, String> getHeaders() throws AuthFailureError {
        HashMap<String, String> headers = new HashMap<String, String>();
        headers.put("Content-Type", "application/json; charset=utf-8");
        headers.put("User-agent", "My useragent");

        return headers;
    }

};
jsonObjReq.setRetryPolicy(new DefaultRetryPolicy(5000,
        DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
        DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
queue.add(jsonObjReq);

}

问题是，如果URL是产品，它将显示数据，否则不会。

Answer 1

将myAdapter声明为私有变量并更改下面提到的代码。

在myAdapter.notifyDataSetChanged();和lstBook.add(new Book(title,"rAJA","Description book",img));

之后添加第myrv.setAdapter(myAdapter);行

for(int i=0;i<jr.length();i++)
 {
    JSONObject jb1 = jr.getJSONObject(i);
    String title = jb1.getString("title");
    String img = jb1.getString("featured_src");
    JSONArray a = jb1.getJSONArray("categories");
    String category = "";
    lstBook.add(new Book(title,"rAJA","Description book",img));
    myAdapter.notifyDataSetChanged();
}

和

myAdapter = new RecyclerViewAdapter(this,lstBook);
myrv.setLayoutManager(new GridLayoutManager(this,2));
myrv.setAdapter(myAdapter);
myAdapter.notifyDataSetChanged();

Recycler查看没有阅读大型排球数据与android中的params

1 个答案: