添加时RecycerView addInArray错误

Question

我尝试在loadordersdata()中的setadapter()之前添加:adapter.notifydatasetchanged()；，但没有任何意义。有人看到是什么引起的吗？

代码如下：

主要活动：

public class CourierActivity extends AppCompatActivity {
    private TableLayout orderTable;
    private RecyclerView recyclerView;
    private RecycleAdapter adapter;
    private List<OrderListItem> listItems;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.courier_main);

        recyclerView = (RecyclerView) findViewById(R.id.rv);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(new LinearLayoutManager(CourierActivity.this));
        adapter = new RecycleAdapter(listItems, getApplicationContext());
        recyclerView.setAdapter(adapter);
        loadOrdersData();
    }

    private void loadOrdersData() {    
        RequestQueue queue = Volley.newRequestQueue(this);
        StringRequest sr = new StringRequest(Request.Method.GET, URL, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                listItems = new ArrayList<>();

                try {
                    String rsp = new String(response.getBytes("ISO-8859-1"), "UTF-8");
                    JSONArray orders = new JSONArray(rsp);

                    for (int i = 0; i < orders.length(); i++) {
                        OrderListItem listItem = new OrderListItem(
                                // .. 
                        );

                        listItems.add(listItem);
                    }

                    adapter = new RecycleAdapter(listItems, getApplicationContext());
                    recyclerView.setAdapter(adapter);
                } catch (JSONException | UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_SHORT);
            }
        }) {

            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                Map<String, String> params = new HashMap<String, String>();
                return params;
            }
        };

        queue.add(sr);
    }
}

public class OrderListItem {
    private String name;
    private String status;
    private String price;
    private String courier;

    public OrderListItem(String name, String status, String price, String courier) {
        this.name = name;
        this.status = status;
        this.price = price;
        this.courier = courier;
    }

    public String getName() { return name; }

    public String getStatus() { return status;}

    public String getPrice() { return price; }

    public String getCourier() { return courier; }
}

public class RecycleAdapter extends RecyclerView.Adapter<RecycleAdapter.ViewHolder> {

    private List<OrderListItem> listItems;
    private Context context;

    public RecycleAdapter(List<OrderListItem> listItems, Context context) {
        this.listItems = listItems;
        this.context = context;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.rv_item, parent, false);

        return new ViewHolder(v);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        OrderListItem listItem = listItems.get(position);

        holder.TextViewName.setText(listItem.getName());
        holder.TextViewStatus.setText(listItem.getStatus());
        holder.TextViewPrice.setText(listItem.getPrice());
        holder.TextViewCourier.setText(listItem.getCourier());
    }

    @Override
    public int getItemCount() {
        int count = 0;

        if (listItems != null && !listItems.isEmpty()) {
            count = listItems.size();
        }

        return count;
    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        public TextView TextViewName;
        public TextView TextViewStatus;
        public TextView TextViewPrice;
        public TextView TextViewCourier;

        public ViewHolder(View itemView) {
            super(itemView);

            TextViewName = (TextView) itemView.findViewById(R.id.orderListName);
            TextViewStatus = (TextView) itemView.findViewById(R.id.orderListStatus);
            TextViewPrice = (TextView) itemView.findViewById(R.id.orderListPrice);
            TextViewCourier = (TextView) itemView.findViewById(R.id.orderListCourier);
        }
    }

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:layout_margin="@dimen/activity_horizontal_margin"
        android:layout_height="wrap_content"
        android:layout_width="match_parent">

        <LinearLayout
            android:padding="@dimen/activity_horizontal_margin"
            android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <TextView
                android:id="@+id/orderListName"
                android:text="Order name"
                android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

            <TextView
                android:id="@+id/orderListStatus"
                android:text="Status"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

            <TextView
                android:id="@+id/orderListPrice"
                android:text="Price"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

            <TextView
                android:id="@+id/orderListCourier"
                android:text="Courier"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
        </LinearLayout>

    </android.support.v7.widget.CardView>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context="com.example.seether.myapplication.CourierActivity"
    android:background="#fff"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/drawerLayout">


    <android.support.v7.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/rv"/>



</android.support.v4.widget.DrawerLayout>

编辑。如果我将自定义数据输入到ListItems中，则不会出现日志警告。

Answer 1

使用

adapter = new RecycleAdapter(listItems, CourierActivity.this);

而不是

adapter = new RecycleAdapter(listItems, getApplicationContext());

还要在RecycerView中添加方向

android:orientation="vertical"

 String rsp = new String(response.getBytes(), "UTF-8");