Android - 获取 JSONArray 问题

Question

在我的安卓应用程序中，我想从网站获取JSON数据。 我创建它是为了使用以下结构获取数据：

[{"id":"1","name":"a"},{"id":"2","name":"a"},{"id":"3","name":"a"},{"id":"4","name":"a"}]

它完全按照应有的方式工作。现在我尝试稍微操作一下代码以获取具有以下结构的其他 JSON data.it：

{"ok":true,"license":"xx","data":"zz","status":"ok","stations":
[{"id":"474","name":"ABC","street":"MARGARETE-STR."},
{"id":"442","name":"XYZ","street":"ABCSTR"}]}

我没有得到任何结果，我认为这可能是因为应该获取的数据位于数组中，但我也认为无论如何我都会得到它。我取错了吗？

我的代码：

public class MainActivity extends AppCompatActivity {
List<GetDataAdapter> GetDataAdapter1;
RecyclerView recyclerView;
RecyclerView.LayoutManager recyclerViewlayoutManager;
RecyclerView.Adapter recyclerViewadapter;
ProgressBar progressBar;
String GET_JSON_DATA_HTTP_URL = "xx.com";
String JSON_ID = "id";
String JSON_NAME = "name";
String JSON_SUBJECT = "email";
String JSON_STREET = "street";
Button button;
JsonArrayRequest jsonArrayRequest;
com.android.volley.RequestQueue requestQueue;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
GetDataAdapter1 = new ArrayList<>();
recyclerView = (RecyclerView) findViewById(R.id.recyclerView1);
progressBar = (ProgressBar) findViewById(R.id.progressBar1);
button = (Button) findViewById(R.id.button);
recyclerView.setHasFixedSize(true);
recyclerViewlayoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(recyclerViewlayoutManager);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
progressBar.setVisibility(View.VISIBLE);
JSON_DATA_WEB_CALL();
}
});
}
public void JSON_DATA_WEB_CALL() {
jsonArrayRequest = new JsonArrayRequest(GET_JSON_DATA_HTTP_URL,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
progressBar.setVisibility(View.GONE);
JSON_PARSE_DATA_AFTER_WEBCALL(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
}
});
requestQueue = Volley.newRequestQueue(this);
requestQueue.add(jsonArrayRequest);
}
public void JSON_PARSE_DATA_AFTER_WEBCALL(JSONArray array) {
for (int i = 0; i < array.length(); i++) {
GetDataAdapter GetDataAdapter2 = new GetDataAdapter();
JSONObject json = null;
try {
json = array.getJSONObject(i);
GetDataAdapter2.setId(json.getInt(JSON_ID));
GetDataAdapter2.setName(json.getString(JSON_NAME));
GetDataAdapter2.setStreet(json.getString(JSON_STREET));
} catch (JSONException e) {
e.printStackTrace();
}
GetDataAdapter1.add(GetDataAdapter2);
}
recyclerViewadapter = new RecyclerViewAdapter(GetDataAdapter1, this);
recyclerView.setAdapter(recyclerViewadapter);
}
}

Answer 1

第二个 JSON示例不是 JSON 数组;它是一个 JSON 对象。应使用JsonObjectRequest而不是JsonArrayRequest来获取此数据。