无法将JSON中的新数据添加到Android中Listview的适配器

我是Android的绝对初学者。我正在学习如何使用截取并将来自截取请求响应的数据绑定到listview。一切正常。但是当我将它绑定到Listview时。这是投掷错误。我的代码有什么问题？这样做正确吗

我的活动课

public class VolleyActivity extends Activity{
    private int lastSawFirstListItem;
    private int itemLoadedOn;
    private ArrayAdapter adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.volley_main);

        Button getBtn = (Button)findViewById(R.id.btn_get_request);
        getBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

            }
        });

        ListView listView = (ListView)findViewById(R.id.volleyListView);
        adapter = new CustomAdapter(this,new Entity[0]);
        listView.setAdapter(adapter);
        String url = "http://api.androidhive.info/feed/feed.json";

        JsonObjectRequest jsonRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject jsonObject) {
                List<Entity> items = new ArrayList<Entity>();
                try{
                    JSONArray jsonArray = jsonObject.getJSONArray("feed");
                    for(int i=0;i<jsonArray.length();i++)
                    {
                        JSONObject item = jsonArray.getJSONObject(i);
                        Entity en = new Entity();
                        en.setId(item.getInt("id"));
                        en.setName(item.getString("name"));
                        en.setUrl(item.getString("url"));
                        items.add(en);
                    }
                    adapter.addAll(items);
                    adapter.notifyDataSetChanged();
                    Toast.makeText(getBaseContext(),"Success",Toast.LENGTH_SHORT).show();
                }
                catch (JSONException e)
                {
                    Toast.makeText(getBaseContext(),e.getMessage(),Toast.LENGTH_SHORT).show();
                }
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {

            }
        });

        Volley.newRequestQueue(getBaseContext()).add(jsonRequest);
  }
}

这是将截击与Listview和绑定数据一起使用的正确方法吗？如何修复此错误

然后，我在自定义适配器中从Entity[]更改为

ArrayList

。这仍然是一个错误

我的带有ArrayList的新自定义适配器类

public class CustomAdapter extends ArrayAdapter<Entity> {
    private final Context context;
    private final ArrayList<Entity> values;

    public CustomAdapter(Context context,ArrayList<Entity> values)
    {
        super(context,-1,values);
        this.context = context;
        this.values = values;
    }

    @Override
    public View getView(int position,View convertView,ViewGroup parent)
    {
        LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View rowView = inflater.inflate(R.layout.list_row,parent,false);
        TextView id_text = (TextView)rowView.findViewById(R.id.row_id);
        TextView name_text = (TextView)rowView.findViewById(R.id.row_name);
        TextView url_text = (TextView)rowView.findViewById(R.id.row_url);
        id_text.setText(values.get(position).getId());
        name_text.setText(values.get(position).getName());
        url_text.setText(values.get(position).getUrl());
        return rowView;
    }
}

01-22 05:09:54.770 1895-1895/? W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0xa6219908)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime: FATAL EXCEPTION: main
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime: android.content.res.Resources$NotFoundException: String resource ID #0x1
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.content.res.Resources.getText(Resources.java:230)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.TextView.setText(TextView.java:3769)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at com.example.newfeeds.newfeeds.CustomAdapter.getView(CustomAdapter.java:36)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.AbsListView.obtainView(AbsListView.java:2159)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.ListView.makeAndAddView(ListView.java:1831)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.ListView.fillDown(ListView.java:674)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.ListView.fillFromTop(ListView.java:735)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.ListView.layoutChildren(ListView.java:1638)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.AbsListView.onLayout(AbsListView.java:1994)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.View.layout(View.java:14008)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewGroup.layout(ViewGroup.java:4373)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1663)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1521)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.LinearLayout.onLayout(LinearLayout.java:1434)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.View.layout(View.java:14008)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewGroup.layout(ViewGroup.java:4373)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.View.layout(View.java:14008)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewGroup.layout(ViewGroup.java:4373)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1663)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1521)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.LinearLayout.onLayout(LinearLayout.java:1434)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.View.layout(View.java:14008)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewGroup.layout(ViewGroup.java:4373)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.View.layout(View.java:14008)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewGroup.layout(ViewGroup.java:4373)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1892)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1711)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.Choreographer.doCallbacks(Choreographer.java:562)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.Choreographer.doFrame(Choreographer.java:532)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:725)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:92)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:137)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5041)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at java.lang.reflect.Method.invokeNative(Native Method)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:511)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
    01-22 05:09:54.774 1895-1895/? E/AndroidRuntime:     at dalvik.system.NativeStart.main(Native Method)
    01-22 05:09:54.778 477-489/? W/ActivityManager:   Force finishing activity com.example.newfeeds.newfeeds/.VolleyActivity
    01-22 05:09:54.894 477-489/? D/dalvikvm: GC_FOR_ALLOC freed 179K, 33% free 9817K/14460K, paused 15ms, total 15ms
    01-22 05:09:55.398 477-490/? W/ActivityManager: Activity pause timeout for ActivityRecord{5334f1a0 u0 com.example.newfeeds.newfeeds/.VolleyActivity}

---

好的，如果我理解正确的话，您使用的是

Entity[]values

，这是一个普通数组，您必须在初始化它时定义它的大小

问题是，使用这个普通数组时，它不能在移动中进行扩展或收缩（我的意思是你不能减少或添加更多项）。所以它的大小和初始化时一样

在您的活动中，您提供的是一个

ArrayList

对象，可以在移动中添加或删除项目

这就是你们在这里面临的冲突

您需要做的是在

Customadapter

中有一个

ArrayList

实例，类似这样

    private final Context context;
    private final ArrayList<Entity> values;

    public CustomAdapter(Context context,ArrayList<Entity> values;
    {
        super(context,-1,values);
        this.context = context;
        this.values = values;
    }

并调用此方法

notifyDataSetChanged（）

，因为您具有使用观察者模式的优势

adapter.notifyDataSetChanged();

您还可以使用

JSON

on查看

listview

population上的一些示例

您必须更像OOP那样思考，创建一个模型类，其实例将为您保存数据

public class Entity {

    private String id;
    private String name;
    private String url;

    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getUrl() {
        return url;
    }
    public void setUrl(String url) {
        this.url = url;
    }
}

更新， 因为有很多困惑，试试这个

公共类ListVewTestThreeActivity扩展了AppCompatActivity{
私有列表视图列表视图；
私有ArrayList实体；
私有MyAdapter MyAdapter；
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity\u list\u vew\u test\u three）；
工具栏工具栏=（工具栏）findViewById（R.id.my\u自定义工具栏）；
设置支持操作栏（工具栏）；
getSupportActionBar（）.setDisplayHomeAsUpEnabled（true）；
初始化（）；
}
private void initializeUI（）{
listView=（listView）findViewById（R.id.ListVewtTestThreeActivity_listView）；
实体=新的ArrayList（）；
myAdapter=新的myAdapter（getApplicationContext（），R.layout.simple\u list\u item\u 1，实体）；
setAdapter（myAdapter）；
新建下载JSON（）.execute（）；
}
私有类下载JSON扩展异步任务{
私有ArrayList实体；
@凌驾
受保护的void onPreExecute（）{
super.onPreExecute（）；
tempEntities=newArrayList（）；
}
@凌驾
受保护的Void doInBackground（Void…参数）{
试一试{
URL=新URL（“http://api.androidhive.info/feed/feed.json");
HttpURLConnection HttpURLConnection=（HttpURLConnection）url.openConnection（）；
httpURLConnection.connect（）；
字符串结果=IOUtils.toString（httpURLConnection.getInputStream（））；
System.out.println（“+”结果）；
JSONObject JSONObject=新JSONObject（结果）；
JSONArray JSONArray=jsonObject.getJSONArray（“提要”）；
for（int i=0；ivalues.addAll(items);

adapter.notifyDataSetChanged();

public class Entity {

    private String id;
    private String name;
    private String url;

    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getUrl() {
        return url;
    }
    public void setUrl(String url) {
        this.url = url;
    }
}

public class ListVewTestThreeActivity extends AppCompatActivity {

    private ListView listView;
    private ArrayList<Entity> entities;
    private MyAdapter myAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list_vew_test_three);
        Toolbar toolbar = (Toolbar) findViewById(R.id.my_custom_toolbar);
        setSupportActionBar(toolbar);

        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        initializeUI();
    }

    private void initializeUI() {
        listView = (ListView) findViewById(R.id.ListVewTestThreeActivity_listView);
        entities = new ArrayList<>();
        myAdapter = new MyAdapter(getApplicationContext(), R.layout.simple_list_item_1, entities);
        listView.setAdapter(myAdapter);

        new DownloadJSON().execute();
    }

    private class DownloadJSON extends AsyncTask<Void, Void, Void> {

        private ArrayList<Entity> tempEntities;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            tempEntities = new ArrayList<>();
        }

        @Override
        protected Void doInBackground(Void... params) {

            try {

                URL url = new URL("http://api.androidhive.info/feed/feed.json");
                HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
                httpURLConnection.connect();

                String result = IOUtils.toString(httpURLConnection.getInputStream());
                System.out.println("" + result);

                JSONObject jsonObject = new JSONObject(result);
                JSONArray jsonArray = jsonObject.getJSONArray("feed");

                for (int i = 0; i < jsonArray.length(); i++) {
                    Entity entity = new Entity();
                    entity.setId(jsonArray.getJSONObject(i).getString("id"));
                    entity.setName(jsonArray.getJSONObject(i).getString("name"));
                    entity.setUrl(jsonArray.getJSONObject(i).getString("image"));
                    System.out.println(""+entity.getName());
                    tempEntities.add(entity);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void aVoid) {
            super.onPostExecute(aVoid);

            if (tempEntities != null) {
                entities.addAll(tempEntities);
                System.out.println("Size: "+entities.size());
                myAdapter.notifyDataSetChanged();
            }

        }
    }


    private class MyAdapter extends ArrayAdapter {

        private ArrayList<Entity> a_productInfos;
        private Context a_context;
        private LayoutInflater a_layoutInflater;

        public MyAdapter(Context context, int resource, ArrayList<Entity> a_productInfos) {
            super(context, resource, a_productInfos);
            this.a_productInfos = a_productInfos;
            this.a_context = context;
            a_layoutInflater = LayoutInflater.from(this.a_context);
        }


        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View row = convertView;
            ViewHolder holder = null;
            if (row == null) {
                row = a_layoutInflater.inflate(R.layout.single_item_listview_test_three, parent, false);
                holder = new ViewHolder();
                holder.id = (TextView) row.findViewById(R.id.ListVewTestThreeActivity_id_textView);
                holder.name = (TextView) row.findViewById(R.id.ListVewTestThreeActivity_name_textView);
                holder.url = (TextView) row.findViewById(R.id.ListVewTestThreeActivity_url_textView);
                row.setTag(holder);
            } else {
                holder = (ViewHolder) row.getTag();
            }

            final Entity productInfo = a_productInfos.get(position);
            holder.id.setText("" + productInfo.getId());
            holder.name.setText("" + productInfo.getName());
            holder.url.setText("" + productInfo.getUrl());
            return row;
        }

        class ViewHolder {
            TextView id;
            TextView name;
            TextView url;
        }

        @Override
        public int getCount() {
            return super.getCount();
        }
    }

    public class Entity {

        private String id;
        private String name;
        private String url;

        public String getId() {
            return id;
        }

        public void setId(String id) {
            this.id = id;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getUrl() {
            return url;
        }

        public void setUrl(String url) {
            this.url = url;
        }
    }
}

    public class VolleyActivity extends Activity{
    private int lastSawFirstListItem;
    private int itemLoadedOn;
    private ArrayAdapter adapter;
    private List<Entity> items;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.volley_main);

        Button getBtn = (Button)findViewById(R.id.btn_get_request);
        getBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

            }
        });
        items = new ArrayList<Entity>();
        ListView listView = (ListView)findViewById(R.id.volleyListView);
        adapter = new CustomAdapter(this, items);
        listView.setAdapter(adapter);
        String url = "http://api.androidhive.info/feed/feed.json";

        JsonObjectRequest jsonRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject jsonObject) {
                List<Entity> items = new ArrayList<Entity>();
                try{
                    JSONArray jsonArray = jsonObject.getJSONArray("feed");
                    for(int i=0;i<jsonArray.length();i++)
                    {
                        JSONObject item = jsonArray.getJSONObject(i);
                        Entity en = new Entity();
                        en.setId(item.getInt("id"));
                        en.setName(item.getString("name"));
                        en.setUrl(item.getString("url"));
                        items.add(en);
                    }
                    adapter.addAll(items);
                    adapter.notifyDataSetChanged();
                    Toast.makeText(getBaseContext(),"Success",Toast.LENGTH_SHORT).show();
                }
                catch (JSONException e)
                {
                    Toast.makeText(getBaseContext(),e.getMessage(),Toast.LENGTH_SHORT).show();
                }
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {

            }
        });

        Volley.newRequestQueue(getBaseContext()).add(jsonRequest);
    }
}

    public class CustomAdapter extends ArrayAdapter<Entity> {
      private final Context context;
      private List<Entity> values;

      public CustomAdapter(Context context,List<Entity> values){
         super(context,-1,values);
         this.context = context;
         this.values = values;
      }

      @Override
      public View getView(int position,View convertView,ViewGroup parent)
      {
          LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
          View rowView = inflater.inflate(R.layout.list_row,parent,false);
          TextView id_text = (TextView)rowView.findViewById(R.id.row_id);
          TextView name_text = (TextView)rowView.findViewById(R.id.row_name);
          TextView url_text = (TextView)rowView.findViewById(R.id.row_url);
          id_text.setText(String.valueOf(values.get(position).getId()));
          name_text.setText(values.get(position).getName());
          url_text.setText(values.get(position).getUrl());
          return rowView;
      }
     }

id_text.setText(String.valueOf(values[position].getId()))

String.valueOf(values.get(position).getId())