Question

我编写了一个代码，用于从服务器检索数据并将其显示在一个简单的列表中，并且它可以成功运行，但是当我使用自定义列表视图“其中每行包含textviews和checkbox”时，它不起作用..

这是我的课程：

public class ItemInList {
private String name;
private float Description;
private boolean selected;

public ItemInList(String name, float Description) {
    this.name = name;
    this.Description =Description;
    selected = false;
}

public String getName() {
    return name;
}

public float getDescription() {
    return Description;
}

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

public void setDescription(float Description) {
    this.Description = Description;
}

public boolean isSelected() {
    return selected;
}

public void setSelected(boolean selected) {
    this.selected = selected;
}

这是适配器类

public class DataAdapter extends ArrayAdapter<ItemInList> {


public ArrayList<ItemInList> list;

public Activity context;
public LayoutInflater inflater;

public DataAdapter(Activity context,int x,ArrayList<ItemInList> list) {
    super(context, 0, list);
    this.context = context;
    this.list = list;
    this.inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

static class ViewHolder {
    protected TextView name,Description;
    protected CheckBox checkbox;
}

public int getCount() {
    // TODO Auto-generated method stub
    return list.size();
}

@Override
public ItemInList getItem(int position) {
    // TODO Auto-generated method stub
    return list.get(position);
}

@Override
public long getItemId(int position) {
    // TODO Auto-generated method stub
    return 0;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    ViewHolder holder;



    if (convertView == null) {

         holder = new ViewHolder();
            convertView = inflater.inflate(R.layout.row1, null);


        holder.name = (TextView) convertView.findViewById(R.id.food_title);
        holder.name.setTextColor(Color.BLACK);

        holder.Description = (TextView) convertView.findViewById(R.id.food_description);
        holder.Description.setTextColor(Color.GRAY);

        holder.checkbox = (CheckBox) convertView.findViewById(R.id.add_food_item);
    //viewHolder.checkbox
                //.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                    //@Override
                    //public void onCheckedChanged(CompoundButton buttonView,
                            //boolean isChecked) {
                        //ItemInList element = (ItemInList) viewHolder.checkbox.getTag();
                        //element.setSelected(buttonView.isChecked());
                        //System.out.println("Checked : " + element.getName());
                    //}
                //});

         convertView.setTag(holder);


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

            ItemInList bean = (ItemInList) list.get(position);

            holder.name.setText( bean.getName());
            holder.Description.setText( bean.getDescription()+"");
            holder.checkbox.setChecked( bean.isSelected());

              return convertView;
    }



    holder.name.setText(list.get(position).getName());
    holder.Description.setText(list.get(position).getDescription()+"");
    holder.checkbox.setChecked(list.get(position).isSelected());

      return convertView;
}

Answer 1

你没有发起

ItemInList item;

在doInBackground（）

中设置值之前

item.setName(foodName);
//...

Answer 2

如果从LoadData.doInBackground（）中删除“return null”，它是否有效？毕竟，它是一个无效函数，不应该返回任何东西。

自定义列表视图中的错误“其中每行包含2个textviews和一个复选框”

2 个答案: