Firebase 数据网格视图项在网格视图中重复出现

Question

请查看我的代码。这段代码实际上从 Firebase 获取值并将其附加到网格视图中，尽管我发现 gridView 使用重复值进行更新，但 onclick 侦听器正确执行，仅提供唯一值。

网格视图具有重复的值，并且它似乎正在随机更改。如果有人可以帮助我完成一些示例工作代码，那将很有帮助。谁能帮我解决这个问题？

public class Materials extends Fragment {
    private Button btnTEST;
    Context context;
    CardView cardview;
    RelativeLayout.LayoutParams layoutparams;
    TextView textview;
    RelativeLayout relativeLayout;
    GridView grid;
    int l=0,fl=0;
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View v= inflater.inflate(R.layout.fragment_materials, container, false);
        context = v.getContext();
        grid=(GridView)v.findViewById(R.id.grid);

        final String[] web=new String[13];
        final int[] imageId = new int[13];

        DatabaseReference ref = FirebaseDatabase.getInstance().getReference("Materials_management_new/Materials/");
        ref.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                if (fl == 0) {
                    for (DataSnapshot snap : dataSnapshot.getChildren()) {
                        web[l] =snap.getKey().toString();
                        l++;
                        fl=1;
                    }
                    //= gson.toJson(dataSnapshot);
                    //  Toast.makeText(LoginPage.this, json, Toast.LENGTH_SHORT).show();
                }
                CustomGrid adapter;
                adapter = new CustomGrid(getContext(), web, imageId);
                grid.setAdapter(adapter);
            }
            @Override
            public void onCancelled(DatabaseError databaseError) {
                System.out.println("The read failed: " + databaseError.getCode());
            }
        });
     //   Toast.makeText(getActivity(), "SUccesssssafmlnfka", Toast.LENGTH_SHORT).show();

        grid.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {
                Toast.makeText(getActivity(), "You Clicked at " +web[+ position], Toast.LENGTH_SHORT).show();
            }
        });

        return v;
    }

}

这是我的自定义网格代码

public class CustomGrid extends BaseAdapter{
    private Context mContext;
    private final String[] web;
    private final int[] Imageid;
    public CustomGrid(Context c,String[] web,int[] Imageid ) {
        mContext = c;
        this.Imageid = Imageid;
        this.web = web;
    }
    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return web.length;
    }
    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return null;
    }
    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0;
    }
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        View grid;
        LayoutInflater inflater = (LayoutInflater) mContext
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (convertView == null) {
            grid = new View(mContext);
            grid = inflater.inflate(R.layout.grid_single, null);
            TextView textView = (TextView) grid.findViewById(R.id.grid_text);
            ImageView imageView = (ImageView)grid.findViewById(R.id.grid_image);
            textView.setText(web[position]);
            imageView.setImageResource(Imageid[position]);
        } else {
            grid = (View) convertView;
        }
        return grid;
    }
}

Answer 1

如果要获得有序的项目列表，可以使用数据库查询对其进行排序，另外为要索引的数据库设置规则，否则整个安装将在客户端完成。

请参阅在 https://firebase.google.com/docs/database/android/lists-of-data?authuser=1 中对数据进行排序和筛选