java - 当所有数据结构都具有有效值时，数组列表和三个数组的客户适配器不会填充 ListView

Question

我有一个数组列表和 3 个数组，它们都包含有效值。我试图将它们显示在数组列表中，但没有显示任何内容。没有任何错误。

这是我的适配器代码:

public class CustomAdapter extends BaseAdapter {
    Context context;
    ArrayList<String> brands;
    int[] ard,chmd,brandTotal;
    LayoutInflater inflater;
    public CustomAdapter(Context context,ArrayList<String> brands,int[] ard, int[] chmd,int[] brandTotal){
        this.context=context;
        this.brands=brands;
        this.ard=ard;
        this.chmd=chmd;
        this.brandTotal=brandTotal;
        inflater = (LayoutInflater)context.
                getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }
    @Override
    public int getCount() {
        return brands.size();
    }

    @Override
    public Object getItem(int position) {
        return position;
    }
    public class Holder
    {
        TextView brand;
        TextView ard;
        TextView chmd;
        TextView total;

    }

    @Override
    public long getItemId(int position) {
        return position;

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Holder holder=new Holder();
        View rowView;
        rowView = inflater.inflate(R.layout.reportview, parent);
        holder.brand=(TextView) rowView.findViewById(R.id.brandText);
        holder.ard=(TextView) rowView.findViewById(R.id.ardCount);
        holder.chmd=(TextView) rowView.findViewById(R.id.chmdCount);
        holder.total=(TextView) rowView.findViewById(R.id.totalCount);
        holder.brand.setText(brands.get(position));
        holder.ard.setText(String.valueOf(ard[position]));
        holder.chmd.setText(String.valueOf(chmd[position]));
        holder.total.setText(String.valueOf(brandTotal[position]));
        return rowView;
    }
}

这是我调用适配器的代码:

public class ReportFragment extends Fragment {


    DatabaseReference db,mdb;
    ArrayList<Item> items=new ArrayList<Item>();
    ArrayList<String> brands =new ArrayList<>();
    Query query;
    ListView listView;
    TextView t1,t2,t3;
    public ReportFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_report, container, false);
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        listView=(ListView)getView().findViewById(R.id.reportList);
        t1=(TextView)getView().findViewById(R.id.ardTotal);
        t2=(TextView)getView().findViewById(R.id.chmdTotal);
        t3=(TextView)getView().findViewById(R.id.total);
        db= FirebaseDatabase.getInstance().getReferenceFromUrl("https://stockmanager-142503.firebaseio.com/Sold");
        mdb=FirebaseDatabase.getInstance().getReferenceFromUrl("https://stockmanager-142503.firebaseio.com/Brands");
        query=db.orderByChild("date");
        query.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot, String s) {
                Item i=dataSnapshot.getValue(Item.class);
                items.add(i);
            }

            @Override
            public void onChildChanged(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onChildRemoved(DataSnapshot dataSnapshot) {

            }

            @Override
            public void onChildMoved(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });
        Query q=mdb.orderByChild("brandName");
        q.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot, String s) {
            brands.add(dataSnapshot.getValue(Brand.class).getBrandName());

            }

            @Override
            public void onChildChanged(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onChildRemoved(DataSnapshot dataSnapshot) {

            }

            @Override
            public void onChildMoved(DataSnapshot dataSnapshot, String s) {

            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });

        }


        t1.setText(String.valueOf(totalArd));
        t2.setText(String.valueOf(totalChmd));
        t3.setText(String.valueOf(itemCount));
    listView.setAdapter(new CustomAdapter(getActivity(),brands,ard,chmd,brandTotal));

    }
}

我的所有数组和数组列表中都有有效数据。我已经通过将它们全部打印出来进行了检查。无法弄清楚适配器为什么不工作。我也没有收到任何错误。请帮帮我。谢谢

Answer 1

您正在将 ListView 高度参数设置为wrap_content，将其更改为match_parent或为其指定固定大小(以dp为单位)