Ho to change ListView items count?

Question

I have a ListView with the sections. And when there is a section, then it takes the place of another. That is, if the ListView items count 30, the section takes the place of the first paragraph, and it turns out that the show only 29 points.

Here is a picture, which shows clearly

Tried TYPE_MAX_COUNT = 2, 3. Without confusing.

@Override
public int getViewTypeCount() {
    return TYPE_MAX_COUNT;
}

I think getViewTypeCount() is triggered after getView().

private List<VacancyModel> vacancyModelList;
    private LayoutInflater inflater;
    private SQLHelper sqlHelper;

    private static final int TYPE_SEPARATOR = 1;
    private static final int TYPE_ITEM = 0;
    private int rowType;

    public static String saveLastDate;
    private int newRecs = 0;

    public SuitableAdapter(Context context, int resource, List<VacancyModel> objects) {
        super(context, resource, objects);
        vacancyModelList = objects;

        sqlHelper = new SQLHelper(getContext());

        inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    @NonNull
    @Override
    public View getView(final int position, View convertView, @NonNull final ViewGroup parent) {
        ViewHolder holder = null;

        rowType = getItemViewType(position);

        if (convertView == null) {
            holder = new ViewHolder();

            switch (rowType) {
                case TYPE_SEPARATOR:
                    convertView = inflater.inflate(R.layout.suitable_separator_layout, null);
                    holder.headerTv = (TextView) convertView.findViewById(R.id.section_header);

                    break;

                case TYPE_ITEM:
                    convertView = inflater.inflate(R.layout.row_layout, null);
                    holder.tvProfession = (TextView) convertView.findViewById(R.id.tvProfession);
                    holder.tvHeader = (TextView) convertView.findViewById(R.id.tvHeader);
                    holder.tvSalary = (TextView) convertView.findViewById(R.id.tvSalary);
                    holder.tvDate = (TextView) convertView.findViewById(R.id.tvPostCr);
                    break;
            }

            convertView.setTag(holder);

        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        if (getItemViewType(position) == TYPE_SEPARATOR) {

            holder.headerTv = (TextView) convertView.findViewById(R.id.section_header);

            if (newRecs == 1) {
                holder.headerTv.setText("Новые вакансии");
                newRecs = 0;
            } else {
                holder.headerTv.setText("Ранее просмотренные");
            }
        }

        if (getItemViewType(position) == TYPE_ITEM) {

            final VacancyModel model = vacancyModelList.get(position);

            holder.tvProfession.setText(model.getProfession());
            holder.tvHeader.setText(model.getHeader());
            holder.tvSalary.setText(model.getSalary());
            holder.tvDate.setText(model.getDate());

            Date date;
            try {
                if (saveLastDate == null) {
                    saveLastDate = model.getDate();
                } else {
                    date = stringToDate(saveLastDate);
                    if (date.before(stringToDate(model.getDate()))) {
                        saveLastDate = model.getDate();
                    }
                }

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

        return convertView;
    }

    @Override
    public int getItemViewType(int position) {
        if (GlobalData.LoadDate(getContext()) == null) {
            return TYPE_ITEM;
        } else {
            VacancyModel model = getItem(position);

            if (model != null) {
                String newString = model.getDate();
                String lastString = GlobalData.LoadDate(getContext());

                Date newDate = null;
                Date lastDate = null;

                try {
                    newDate = stringToDate(newString);
                    lastDate = stringToDate(lastString);
                } catch (ParseException e) {
                    e.printStackTrace();
                }

                assert newDate != null;

                if (newDate.equals(lastDate)) {
                    return TYPE_SEPARATOR;
                } else if (position == 0 && newDate.after(lastDate)) {
                    newRecs = 1;
                    return TYPE_SEPARATOR;
                } else {
                    return TYPE_ITEM;
                }
            } else {
                return TYPE_ITEM;
            }
        }
    }

    @Override
    public int getViewTypeCount() {
        return 3;
    }

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

    private Date stringToDate(String string) throws ParseException {
        return new SimpleDateFormat(("yyyy-MM-dd HH:mm:ss"), Locale.getDefault()).parse(string);
    }

    private static class ViewHolder {
        private TextView tvProfession;
        private TextView tvHeader;
        private TextView tvSalary;
        private TextView tvDate;

        private TextView headerTv;
    }

VacancyModel

public class VacancyModel implements Serializable{
    private String profession;
    private String header;
    private String salary;
    private String date;


    public VacancyModel() {
    }

    public String getProfession() {
        return profession;
    }

    public void setProfession(String profession) {
        this.profession = profession;
    }

    public String getHeader() {
        return header;
    }

    public void setHeader(String header) {
        this.header = header;
    }

    public String getSalary() {
        if (salary.equals("0") || salary.isEmpty() || salary.equals("null")){
            return "empty";
        }
        else {
            return salary;
        }
    }

    public void setSalary(String salary) {
        this.salary = salary;
    }

    public String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

}

Question: What I am doing wrong and how to change ListView`s count?

Answer 1

The listItem you are sending in should have the type field as well. So what I am suggesting is instead of doing date check manipulation inside listview. you can do it prior before adding data to RecyclerView.

Adding two more Field to your Serializable Data:

public class VacancyModel implements Serializable{
    private String profession;
    private String header;
    private String salary;
    private String date;
   // set setter and getter for both, by default isHeading will be false,
    private boolean isHeading;
    private String heading;


    public VacancyModel() {
    }

    public String getProfession() {
        return profession;
    }

    public void setProfession(String profession) {
        this.profession = profession;
    }

    public String getHeader() {
        return header;
    }

    public void setHeader(String header) {
        this.header = header;
    }

    public String getSalary() {
        if (salary.equals("0") || salary.isEmpty() || salary.equals("null")){
            return "empty";
        }
        else {
            return salary;
        }
    }

    public void setSalary(String salary) {
        this.salary = salary;
    }

    public String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

}

Do the following thing inside your activity inside activity:

   private void generateListHeading(List<VacancyModel> original_vacany_list)
    {

      List<VacancyModel> vacancy_type_new_record;
     VacancyModel model = new vacacyModel();
      model.setIsHeading(true); 
      model.setHeading("New Record");
    vacancy_type_new_record.add(model);
    List<VacancyModel> vacancy_type_watched;
    model = new vacacyModel();
      model.setIsHeading(true); 
      model.setHeading("Watched");
    vacancy_type_watched.add(model);

      List<VacancyModel> new_vacancy_list;
    for(VacanyModel  data:original_vacany_list)
    {
       //do your date condition check here
       if(data.getDate==newDate)
      {
         vacancy_type_new_record.add(data) 
      } else
      {
           vacancy_type_watched.add(data) 
      }
    }
    //once the whole condition check is add both list to new list
    new_vacancy_list.addAll(vacancy_type_new_record); 
    new_vacancy_list.addAll(vacancy_type_watched); 
    //now the item count will be 32. in the format heading ,data ,heading,data
    adapter.setUpdateddata(new_vacancy_list);
      }

Adapter.class:

  vacanyModelList = new ArrayList<>();
    public SuitableAdapter(Context context, int resource) {
            super(context, resource, objects);
            //don't set your object in constructor
            sqlHelper = new SQLHelper(getContext());

            inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        }

        @NonNull
        @Override
        public View getView(final int position, View convertView, @NonNull final ViewGroup parent) {
            ViewHolder holder = null;

            rowType = getItemViewType(position);

            if (convertView == null) {
                holder = new ViewHolder();

                switch (rowType) {
                    case TYPE_SEPARATOR:
                        convertView = inflater.inflate(R.layout.suitable_separator_layout, null);
                        holder.headerTv = (TextView) convertView.findViewById(R.id.section_header);

                        break;

                    case TYPE_ITEM:
                        convertView = inflater.inflate(R.layout.row_layout, null);
                        holder.tvProfession = (TextView) convertView.findViewById(R.id.tvProfession);
                        holder.tvHeader = (TextView) convertView.findViewById(R.id.tvHeader);
                        holder.tvSalary = (TextView) convertView.findViewById(R.id.tvSalary);
                        holder.tvDate = (TextView) convertView.findViewById(R.id.tvPostCr);
                        break;
                }

                convertView.setTag(holder);

            } else {
                holder = (ViewHolder) convertView.getTag();
            }

            if (getItemViewType(position) == TYPE_SEPARATOR) {

                holder.headerTv = (TextView) convertView.findViewById(R.id.section_header);

                if (newRecs == 1) {
                    holder.headerTv.setText("Новые вакансии");
                    newRecs = 0;
                } else {
                    holder.headerTv.setText("Ранее просмотренные");
                }
            }

            if (getItemViewType(position) == TYPE_ITEM) {

                final VacancyModel model = vacancyModelList.get(position);

                holder.tvProfession.setText(model.getProfession());
                holder.tvHeader.setText(model.getHeader());
                holder.tvSalary.setText(model.getSalary());
                holder.tvDate.setText(model.getDate());

                Date date;
                try {
                    if (saveLastDate == null) {
                        saveLastDate = model.getDate();
                    } else {
                        date = stringToDate(saveLastDate);
                        if (date.before(stringToDate(model.getDate()))) {
                            saveLastDate = model.getDate();
                        }
                    }

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

            return convertView;
        }

        @Override
        public int getItemViewType(int position) {
          VacancyModel model = getItem(position);
            if (model.isHeading) {
                return TYPE_SEPARATOR;
            } else {
              return TYPE_ITEM;
                   }
            }
        }

        @Override
        public int getViewTypeCount() {
            return 2;
        }

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

        private Date stringToDate(String string) throws ParseException {
            return new SimpleDateFormat(("yyyy-MM-dd HH:mm:ss"), Locale.getDefault()).parse(string);
        }

        private static class ViewHolder {
            private TextView tvProfession;
            private TextView tvHeader;
            private TextView tvSalary;
            private TextView tvDate;

            private TextView headerTv;
        }

        public void setUpdatedData(List<VacancyModel> updated_list)
        {
          this.vacancyModelList = updated_list;
          notifyDataSetChanged();
        }