解析来自 JSON 的数据后，Recyclerview 中的数据未显示

Question

我正在尝试从本地资产文件夹中解析 JSON 对象。我有一个数组名称联系人。在公司内部，我有对象行名、电子邮件、手机等。我尝试使用以下代码。但是在运行应用程序之后我得到了空页面。我没有弄错哪一行。我的模型 class 看起来像这样。

public class MyColleageModel {
private String _id;
private String dn;
private String mobile;
private String mail;
private String name ;
private String company ;
private String department;
private String title ;
private int __v ;
private String updated_at;

public MyColleageModel() {

}

public MyColleageModel(String mobile, String mail, String name, String company, String department, String title) {
    this.mobile = mobile;
    this.mail = mail;
    this.name = name;
    this.company = company;
    this.department = department;
    this.title = title;
}

public String get_id() {
    return _id;
}

public String getDn() {
    return dn;
}

public String getMobile() {
    return mobile;
}

public String getMail() {
    return mail;
}

public String getName() {
    return name;
}

public String getCompany() {
    return company;
}

public String getDepartment() {
    return department;
}

public String getTitle() {
    return title;
}

public int get__v() {
    return __v;
}

public String getUpdated_at() {
    return updated_at;
}

public void setMobile(String mobile) {
    this.mobile = mobile;
}

public void setMail(String mail) {
    this.mail = mail;
}

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

public void setCompany(String company) {
    this.company = company;
}

public void setDepartment(String department) {
    this.department = department;
}

public void setTitle(String title) {
    this.title = title;
}

}

我的主要 Activity Class 是

public class MyColleaguesPage extends AppCompatActivity {

private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private List<MyColleageModel> colleagueObject;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.mycolleagues_layout);
    recyclerView = (RecyclerView) findViewById(R.id.colleagues_recycler);
    recyclerView.setHasFixedSize(true);
    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
    recyclerView.setLayoutManager(layoutManager);

    colleagueObject = new ArrayList<MyColleageModel>();

    try {

        JSONObject obj = new JSONObject(loadJSONFromAsset());
        JSONArray m_jArry = obj.getJSONArray("contacts");
        ArrayList<HashMap<String, String>> formList = new ArrayList<HashMap<String, String>>();
        HashMap<String, String> m_li;

        MyColleageModel my_clg;
        for (int i = 0; i < m_jArry.length(); i++) {
            JSONObject jo_inside = m_jArry.getJSONObject(i);
            my_clg=new MyColleageModel();
            String val1 = jo_inside.getString("mobile");
            String val2 = jo_inside.getString("mail");
            String val3 = jo_inside.getString("name");
            String val4 = jo_inside.getString("company");
            String val5 = jo_inside.getString("department");
            String val6 = jo_inside.optString("title");

            //Add your values in your `ArrayList` as below:
            m_li = new HashMap<String, String>();
            m_li.put("mobile", val1);
            m_li.put("mail", val2);
            m_li.put("name", val3);
            m_li.put("company", val4);
            m_li.put("department", val5);
            m_li.put("title", val6);

            colleagueObject.add(my_clg);
            formList.add(m_li);
        }


    } catch (JSONException e) {
        e.printStackTrace();
    }

    adapter = new MyColleaguesAdapter(colleagueObject, this);
    recyclerView.setAdapter(adapter);
}

我的 JSON 文件看起来像这样-

  {
  "contacts":[
      {
        "_id": "57f762f1aa44f7230b8f5bb0",
        "dn": "CN=Andreas Oswald,OU=Mitarbeiter,OU=Kelten,DC=blu-pa,DC=com",
        "mobile": "+491733630322",
        "mail": "andreas.oswald@blu-pa.com",
        "name": "Andreas Oswald",
        "company": "blu Portals & Applications GmbH",
        "department": "Roche",
        "title": "externer Mitarbeiter",
        "__v": 0,
        "updated_at": "2016-10-07T08:55:13.909Z"
      },
      {
        "_id": "57f762f2aa44f7230b8f5bb1",
        "dn": "CN=Bernard Landgraf,OU=Mitarbeiter,OU=Kelten,DC=blu-pa,DC=com",
        "mobile": "+4917610660687",
        "mail": "bernard.landgraf@blu-pa.com",
        "name": "Bernard Landgraf",
        "company": "blu Portals & Applications GmbH",
        "department": "Inhouse",
        "__v": 0,
        "updated_at": "2016-10-07T08:55:13.935Z"
      },
      { ........lot of object similar like the above 2

我的适配器Class

public class MyColleaguesAdapter extends RecyclerView.Adapter<MyColleaguesAdapter.ColleagueHolder> {

private List<MyColleageModel> colleagueObject;
private Context context;

public MyColleaguesAdapter(List<MyColleageModel> colleagueObject, Context context) {
    this.colleagueObject = colleagueObject;
    this.context = context;
}

@Override
public ColleagueHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view= LayoutInflater.from(parent.getContext())
            .inflate(R.layout.colleage_row_layout,parent,false);
    return new ColleagueHolder(view);
}

@Override
public void onBindViewHolder(ColleagueHolder holder, int position) {
    MyColleageModel myColleague=colleagueObject.get(position);
    //holder.colleaguePicture.setImageResource(myColleague.getImageResourceId());
    holder.mobile.setText(myColleague.getMobile());
    holder.mail.setText(myColleague.getMail());
    holder.name.setText(myColleague.getName());
    holder.company.setText(myColleague.getCompany());
    holder.department.setText(myColleague.getDepartment());
    holder.title.setText(myColleague.getTitle());

}

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

public class ColleagueHolder extends RecyclerView.ViewHolder{

    public ImageView colleaguePicture;
    public TextView mobile;
    public TextView mail;
    public TextView name;
    public TextView company;
    public TextView department;
    public TextView title;

    public ColleagueHolder(View itemView) {
        super(itemView);
        //colleaguePicture=(ImageView)itemView.findViewById(R.drawable.profile_image);
        mobile=(TextView)itemView.findViewById(R.id.colleague_mobile);
        mail=(TextView) itemView.findViewById(R.id.colleague_mail);
        name=(TextView) itemView.findViewById(R.id.colleague_name);
        company=(TextView)itemView.findViewById(R.id.company_name);
        department=(TextView) itemView.findViewById(R.id.department_name);
        title=(TextView) itemView.findViewById(R.id.job_title);
      }
    }
 }

Answer 1

查看代码。

MyColleageModel my_clg;
for (int i = 0; i < m_jArry.length(); i++) {

        JSONObject jo_inside = m_jArry.getJSONObject(i);

        String val1 = jo_inside.getString("mobile");
        String val2 = jo_inside.getString("mail");
        String val3 = jo_inside.getString("name");
        String val4 = jo_inside.getString("company");
        String val5 = jo_inside.getString("department");
        String val6 = jo_inside.optString("title");

        my_clg = new MyColleageModel(val1,val2,val3,val4,val5,val6);
        // here set the data on my_clg object using setters methods.

        // here add this object to list.
        colleagueObject.add(my_clg);
        formList.add(m_li);
    }

Answer 2

public class MyColleaguesAdapter extends RecyclerView.Adapter {


    private View view;
    Context context;
   List<MyColleageModel> colleagueObject

  public MyColleaguesAdapter(List<MyColleageModel> colleagueObject, Context context) {
    this.colleagueObject = colleagueObject;
    this.context = context;
}
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
     view= LayoutInflater.from(parent.getContext())
            .inflate(R.layout.colleage_row_layout,parent,false);
    return new ColleagueHolder(view);
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder1, int position) {
        final ColleagueHolder holder= (ColleagueHolder ) holder;
       MyColleageModel myColleague=colleagueObject.get(position);

    holder.mobile.setText(myColleague.getMobile());
    holder.mail.setText(myColleague.getMail());
    holder.name.setText(myColleague.getName());
    holder.company.setText(myColleague.getCompany());
    holder.department.setText(myColleague.getDepartment());
    holder.title.setText(myColleague.getTitle());
    }

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

 public class ColleagueHolder extends RecyclerView.ViewHolder{

    public ImageView colleaguePicture;
    public TextView mobile;
    public TextView mail;
    public TextView name;
    public TextView company;
    public TextView department;
    public TextView title;

    public ColleagueHolder(View itemView) {
        super(itemView);
        //colleaguePicture=(ImageView)itemView.findViewById(R.drawable.profile_image);
        mobile=(TextView)itemView.findViewById(R.id.colleague_mobile);
        mail=(TextView) itemView.findViewById(R.id.colleague_mail);
        name=(TextView) itemView.findViewById(R.id.colleague_name);
        company=(TextView)itemView.findViewById(R.id.company_name);
        department=(TextView) itemView.findViewById(R.id.department_name);
        title=(TextView) itemView.findViewById(R.id.job_title);
      }
    }

}

尝试此代码，如果它没有解决您的问题，那么 post 您的 xml

Answer 3

非常感谢你帮我解决了我的问题。这里我修改了正确答案。我在 Main Activity Class.

中遇到问题

public class MyColleaguesPage extends AppCompatActivity {

private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private List<MyColleageModel> colleagueObject;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.mycolleagues_layout);
    recyclerView = (RecyclerView) findViewById(R.id.colleagues_recycler);
    recyclerView.setHasFixedSize(true);
    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
    recyclerView.setLayoutManager(layoutManager);

    colleagueObject = new ArrayList<MyColleageModel>();

    try {

        JSONObject obj = new JSONObject(loadJSONFromAsset());
        JSONArray m_jArry = obj.getJSONArray("contacts");
        ArrayList<HashMap<String, String>> formList = new ArrayList<HashMap<String, String>>();
        HashMap<String, String> m_li;

        MyColleageModel my_clg;
        for (int i = 0; i < m_jArry.length(); i++) {
            JSONObject jo_inside = m_jArry.getJSONObject(i);
            //my_clg=new MyColleageModel();
            String val1 = jo_inside.getString("mobile");
            String val2 = jo_inside.getString("mail");
            String val3 = jo_inside.getString("name");
            String val4 = jo_inside.optString("company");
            String val5 = jo_inside.optString("department");
            String val6 = jo_inside.optString("title");
            my_clg = new MyColleageModel(val1,val2,val3,val4,val5,val6);

            colleagueObject.add(my_clg);

        }


    } catch (JSONException e) {
        e.printStackTrace();
    }

    adapter = new MyColleaguesAdapter(colleagueObject, this);
    recyclerView.setAdapter(adapter);
}

 private String loadJSONFromAsset() {
    String json = null;
    try {

        InputStream is = getAssets().open("colleagues.json");

        int size = is.available();

        byte[] buffer = new byte[size];

        is.read(buffer);

        is.close();

        json = new String(buffer, "UTF-8");


    } catch (IOException ex) {
        ex.printStackTrace();
        return null;
    }
    return json;
  }
}

解析来自 JSON 的数据后，Recyclerview 中的数据未显示

Data in Recyclerview is not showing after parsing data from JSON

android

json

android-json

android-cardview

android-recyclerview