Question

我正在创建一个Android应用程序，它从API中提取信息并将其显示在Recyclerview中。但是一切正常，当应用程序打开时我只有1 GET request（使用Volley）。

我想让回收站视图中的信息每5秒更新一次。我是Java的新手，无法在线找到任何其他问题或资源，解释如何最有效地保持活动API中的信息最新。我应该每隔5秒Get Request，如果是这样，你最好如何实现这一点？如果没有，是否有更合适的方式。

任何反馈都会对我有所帮助，而且我确定一群未来的开发者。我目前的代码是为了参考。

MainActivity.java：

public class MainActivity extends AppCompatActivity {


    private static final String URL_DATA = "https://summerproject17.herokuapp.com/api/request/";
    private RecyclerView recyclerView;
    private RecyclerView.Adapter adapter;

    private List<ListItem> listItems;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));

        listItems = new ArrayList<>();

        loadRecyclerViewData();
    }

    private void loadRecyclerViewData(){
        StringRequest stringRequest = new StringRequest(Request.Method.GET,
                URL_DATA,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        try {
                            JSONObject jsonObject = new JSONObject(response);
                            JSONArray array = jsonObject.getJSONArray("results");

                            for(int i = 0; i < array.length(); i++){
                                JSONObject o = array.getJSONObject(i);
                                ListItem item = new ListItem(
                                        o.getString("room"),
                                        o.getString("request"),
                                        o.getString("time")
                                );
                                listItems.add(item);
                            }

                            adapter = new MyAdapter(listItems, getApplicationContext());
                            recyclerView.setAdapter(adapter);

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Log.e("VOLLEY", error.getMessage());
                    }
                });
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        requestQueue.add(stringRequest);
    }
}

MyAdapter.Java：

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

    private List<ListItem> listItems;
    private Context context;

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

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

    }

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

        holder.textViewHead.setText(listItem.getHead());
        holder.textViewDesc.setText(listItem.getDesc());
    }

    @Override
    public int getItemCount() {
        return listItems.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        public TextView textViewHead;
        public TextView textViewDesc;

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

            textViewHead = (TextView) itemView.findViewById(R.id.textViewHead);
            textViewDesc = (TextView) itemView.findViewById(R.id.textViewDesc);
        }
    }
}

Answer 1

请尝试此解决方案

"3.14159265358979323846"

使用Android和Recyclerview保持API数据的新鲜感

1 个答案: