如何将JSOnObject转换为Array

Question

我是JSON的新手，在尝试获取数据时，我会收到以下错误E/Volley: com.android.volley.ParseError: org.json.JSONException:

编辑：

完整堆栈跟踪：

2020-11-10 20:06:48.606 10505-10505/com.madcoderz.jsonparsing E/Volley: com.android.volley.ParseError: org.json.JSONException: Value {"message":{"affenpinscher":[],"african":[],"airedale":[],"akita":[],"appenzeller":[],"australian":["shepherd"],"basenji":[],"beagle":[],"bluetick":[],"borzoi":[],"bouvier":[],"boxer":[],"brabancon":[],"briard":[],"buhund":["norwegian"],"bulldog":["boston","english","french"],"bullterrier":["staffordshire"],"cairn":[],"cattledog":["australian"],"chihuahua":[],"chow":[],"clumber":[],"cockapoo":[],"collie":["border"],"coonhound":[],"corgi":["cardigan"],"cotondetulear":[],"dachshund":[],"dalmatian":[],"dane":["great"],"deerhound":["scottish"],"dhole":[],"dingo":[],"doberman":[],"elkhound":["norwegian"],"entlebucher":[],"eskimo":[],"finnish":["lapphund"],"frise":["bichon"],"germanshepherd":[],"greyhound":["italian"],"groenendael":[],"havanese":[],"hound":["afghan","basset","blood","english","ibizan","plott","walker"],"husky":[],"keeshond":[],"kelpie":[],"komondor":[],"kuvasz":[],"labrador":[],"leonberg":[],"lhasa":[],"malamute":[],"malinois":[],"maltese":[],"mastiff":["bull","english","tibetan"],"mexicanhairless":[],"mix":[],"mountain":["bernese","swiss"],"newfoundland":[],"otterhound":[],"ovcharka":["caucasian"],"papillon":[],"pekinese":[],"pembroke":[],"pinscher":["miniature"],"pitbull":[],"pointer":["german","germanlonghair"],"pomeranian":[],"poodle":["miniature","standard","toy"],"pug":[],"puggle":[],"pyrenees":[],"redbone":[],"retriever":["chesapeake","curly","flatcoated","golden"],"ridgeback":["rhodesian"],"rottweiler":[],"saluki":[],"samoyed":[],"schipperke":[],"schnauzer":["giant","miniature"],"setter":["english","gordon","irish"],"sheepdog":["english","shetland"],"shiba":[],"shihtzu":[],"spaniel":["blenheim","brittany","cocker","irish","japanese","sussex","welsh"],"springer":["english"],"stbernard":[],"terrier":["american","australian","bedlington","border","dandie","fox","irish","kerryblue","lakeland","norfolk","norwich","patterdale","russell","scottish","sealyham","silky","tibetan","toy","westhighland","wheaten","yorkshire"],"vizsla":[],"waterdog":["spanish"],"weimaraner":[],"whippet":[],"wolfhound":["irish"]},"status":"success"} of type org.json.JSONObject cannot be converted to JSONArray

JSON数据：https://dog.ceo/api/breeds/list/all

我在SO挖了很多东西，但似乎找不到正确的方法

这是我迄今为止写的代码：

private void getData() {
final ProgressDialog progressDialog = new ProgressDialog(this);
progressDialog.setMessage("Loading...");
progressDialog.show();
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(url, new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
for (int i = 0; i < response.length(); i++) {
try {
JSONObject jsonObject = response.getJSONObject(i);
Article article = new Article();
article.setImage(jsonObject.getString("image"));
article.setTitle(jsonObject.getString("title"));
article.setBody(jsonObject.getString("body"));
articles.add(article);

} catch (JSONException e) {
e.printStackTrace();
progressDialog.dismiss();
}
}
adaptor.setData(articles);
adaptor.notifyDataSetChanged();
progressDialog.dismiss();
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e("Volley", error.toString());
progressDialog.dismiss();
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(jsonArrayRequest);
}

}

Answer 1

答案是我使用了错误的URL，JSON调用需要一个JSONArray而不是JSONObject。以下是解决问题的代码：

private void fetchElements(){
RequestQueue requestQueue = Volley.newRequestQueue(this);
JsonObjectRequest objectRequest = new JsonObjectRequest(Request.Method.GET, JSON_URL,
null, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
try {
JSONArray breedsList = response.getJSONArray("message");
for (int i=0; i < breedsList.length(); i++){
Cat cat = new Cat();
cat.setCatBreed(breedsList.getString(i));
cats.add(cat);
}
} catch (JSONException e) {
e.printStackTrace();
}
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
catAdapter = new CatAdapter(getApplicationContext(), cats);
recyclerView.setAdapter(catAdapter);
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
requestQueue.add(objectRequest);
}