如何将json数据从json数组解析到recyclerview java android？

Posted 2023-04-19

【中文标题】如何将json数据从json数组解析到recyclerview java android？

【英文标题】：How to parse json data from json array to recyclerview java android?

【发布时间】：2021-11-19 19:58:06

【问题描述】：

我可以将 json 数据解析到我的 recyclerview。但是当我遇到其中包含数组数据的 json 时，当我尝试获取它时，我的应用程序会强制关闭。如何解决这个问题？或者任何人都有与此案例类似的示例代码？

API：

https://v1.nocodeapi.com/fariz/fit/FunuohzdbtxBkVtC/aggregatesDatasets?dataTypeName=steps_count,heart_minutes,weight,activity_summary

Activity_Stepcounter.java

Call<nodeApi> call = jsonPlaceHolderApi.getNode();
        call.enqueue(new Callback<nodeApi>() 
            @Override
            public void onResponse(Call<nodeApi> call, Response<nodeApi> response) 
                progressBar.setVisibility(View.GONE);

                nodeApi resource = response.body();
                List<nodeApi.steps_count> dataList = resource.steps_count;

                Adapter_meeting rv_adapter = new Adapter_meeting(dataList, Activity_Stepcounter.this);
                rv.setLayoutManager(new LinearLayoutManager(Activity_Stepcounter.this));
                rv.setAdapter(rv_adapter);
                rv.hasFixedSize();
                rv_adapter.notifyDataSetChanged();
            

            @Override
            public void onFailure(Call<nodeApi> call, Throwable t) 
                call.cancel();
            
        );

Adapter_meeting.java

public class Adapter_meeting extends RecyclerView.Adapter<Adapter_meeting.viewHolder> 
private final List<nodeApi.steps_count> mitem_meeting;
private final Context mContext;


public Adapter_meeting(List<nodeApi.steps_count> Item_meeting, Context mContext) 
    this.mitem_meeting = Item_meeting;
    this.mContext = mContext;
    

@NonNull
@Override
public viewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) 
    final View view;
    view = LayoutInflater.from(parent.getContext()).inflate(R.layout.rv_step_counter, parent, false);
    final viewHolder vHolder = new viewHolder(view);
    return vHolder;


@Override
public void onBindViewHolder(@NonNull viewHolder holder, int position) 
    holder.tv_namaEvent.setText(mitem_meeting.get(position).getValue());
    holder.tv_lokasiEvent.setText(mitem_meeting.get(position).getStartTime());
    holder.tv_waktuEvent.setText(mitem_meeting.get(position).getEndTime());
    holder.tv_tanggalEvent.setText(mitem_meeting.get(position).getStartTimeMillis());


@Override
public int getItemCount() 
    return mitem_meeting.size();


public class viewHolder extends RecyclerView.ViewHolder 
    private final TextView tv_namaEvent;
    private final TextView tv_lokasiEvent;
    private final TextView tv_waktuEvent;
    private final TextView tv_tanggalEvent;

    public viewHolder(@NonNull View itemView) 
        super(itemView);

        tv_namaEvent = (TextView) itemView.findViewById(R.id.id_tv_namaEvent);
        tv_lokasiEvent = (TextView) itemView.findViewById(R.id.id_tv_lokasiEvent);
        tv_waktuEvent = (TextView) itemView.findViewById(R.id.id_tv_waktuEvent);
        tv_tanggalEvent = (TextView) itemView.findViewById(R.id.id_tv_tanggalEvent);
    

JsonPlaceHolderApi.java

public interface JsonPlaceHolderApi 
   @GET("aggregatesDatasets?dataTypeName=steps_count,heart_minutes,weight,activity_summary")
Call<nodeApi> getNode();

nodeApi.java

public class nodeApi 

    @SerializedName("steps_count")
    public List<steps_count> steps_count = null;

    public class steps_count 
        public Integer value;
        public String startTimeMillis;
        public String endTimeMillis;
        public String startTime;
        public String endTime;

        public steps_count(Integer value, String startTimeMillis, String endTimeMillis, String startTime, String endTime) 
            this.value = value;
            this.startTimeMillis = startTimeMillis;
            this.endTimeMillis = endTimeMillis;
            this.startTime = startTime;
            this.endTime = endTime;
        

        public Integer getValue() 
            return value;
        

        public void setValue(Integer value) 
            this.value = value;
        

        public String getStartTimeMillis() 
            return startTimeMillis;
        

        public void setStartTimeMillis(String startTimeMillis) 
            this.startTimeMillis = startTimeMillis;
        

        public String getEndTimeMillis() 
            return endTimeMillis;
        

        public void setEndTimeMillis(String endTimeMillis) 
            this.endTimeMillis = endTimeMillis;
        

        public String getStartTime() 
            return startTime;
        

        public void setStartTime(String startTime) 
            this.startTime = startTime;
        

        public String getEndTime() 
            return endTime;
        

        public void setEndTime(String endTime) 
            this.endTime = endTime;
        
    

错误

E/androidRuntime: FATAL EXCEPTION: main
    Process: com.iot.testapp, PID: 12849
    android.content.res.Resources$NotFoundException: String resource ID #0x19
        at android.content.res.Resources.getText(Resources.java:335)
        at android.widget.TextView.setText(TextView.java:4555)
        at com.iot.testapp.adapter.Adapter_meeting.onBindViewHolder(Adapter_meeting.java:47)
        at com.iot.testapp.adapter.Adapter_meeting.onBindViewHolder(Adapter_meeting.java:26)

【参考方案1】：

在这些方面：

holder.tv_tanggalEvent.setText(mitem_meeting.get(position).getStartTimeMillis());
holder.tv_lokasiEvent.setText(mitem_meeting.get(position).getStartTime());
holder.tv_waktuEvent.setText(mitem_meeting.get(position).getEndTime());

编译器认为，您传递的是字符串资源，但实际上传递的是简单字符串。只需添加 +"" 即可开始工作。

holder.tv_tanggalEvent.setText(mitem_meeting.get(position).getStartTimeMillis()+"");    
holder.tv_namaEvent.setText(mitem_meeting.get(position).getStartTime()+"");
holder.tv_waktuEvent.setText(mitem_meeting.get(position).getEndTime()+"");

您应该将文本以带有占位符的字符串资源的形式传递给 textviews，但是当您除了更改的值之外什么都不传递时，它实际上没有任何意义。

【参考方案2】：

holder.tv_namaEvent.setText(mitem_meeting.get(position).getValue());

您正在尝试设置 Int. 试试：

String value = String.valueOf(mitem_meeting.get(position).getValue());
holder.tv_namaEvent.setText(value);

请检查所有字段是否为 null 并阅读 Android 中的命名约定 :)

Milis 中的时间也应该以 Long 类型存储。 您还可以阅读 Kotlin 语言、mvvn 模式等。

【参考方案3】：

谢谢，我从 discord 那里得到了帮助

我必须先制作 jsonresponse，然后使用 nodeApi.java 将其转换为 arraylist。

public class JsonResponse 
    private nodeApi[] steps_count;

    public nodeApi[] getStep_count() 
        return steps_count;
    

    public void setnodeApi(nodeApi[] step_count) 
        this.steps_count = step_count;
    

Activity_Stepcounter.java

 Call<JsonResponse> call = jsonPlaceHolderApi.getStep();
        call.enqueue(new Callback<JsonResponse>() 
            @Override
            public void onResponse(Call<JsonResponse> call, Response<JsonResponse> response) 
                progressBar.setVisibility(View.GONE);

                JsonResponse jsonResponse = response.body();
                listStep = new ArrayList<>(Arrays.asList(jsonResponse.getStep_count()));


                Adapter_meeting rv_adapter = new Adapter_meeting(listStep, Activity_Stepcounter.this);
                rv.setLayoutManager(new LinearLayoutManager(Activity_Stepcounter.this));
                rv.setAdapter(rv_adapter);
                rv.hasFixedSize();
                rv_adapter.notifyDataSetChanged();
            

            @Override
            public void onFailure(Call<JsonResponse> call, Throwable t) 
                call.cancel();
            
        );

**有一些重构/重命名。