Question

我正在开发小型益智Android应用程序，在数据库上有102个谜题。我将Adapter与TextViews和Button用于ListView。

在适配器中我有TextView作为显示谜题的puzzl，回答为TextView以显示答案（默认情况下，它在xml上显示GONE）。当用户按下answer_button TextView时，答案显示答案（answer.setVisibility(View.VISIBLE);）。

一切正常，但我发现有问题。如果我按下第一个答案的按钮以查看ListView，它显示第一个答案，但从下面也打开其他答案，例如5,11,16等。如果我按下第二个回答的按钮，则显示第二个回答和第7个，第12个回答，依此类推。一切都在开放。

我想让按钮必须只显示用户选择的答案。请帮帮我，告诉我我在适配器或ListView上的错误在哪里？非常感谢你。

    public class PuzzleAdapter extends BaseAdapter{

    Context context;
        LayoutInflater inflater;
        List<Puzzles> puzzles;

    public PuzzleAdapter(Context context1, List<Puzzles> p1){
        this.context=context1;
        this.puzzles =p1;
        inflater = (LayoutInflater)this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

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

    @Override
    public Object getItem(int i) {
        return puzzles.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {

        if (view == null){
            view = inflater.inflate(R.layout.puzzle_adapter, null);
        }

        final Puzzles puzz = this.puzzles.get(i);

        TextView puzzl=(TextView)view.findViewById(R.id.puzzl);
        puzzl.setText(puzz.getZagad());

        final TextView answer=(TextView)view.findViewById(R.id.answer);
        answer.setText(puzz.getOtveti());

        final Button answer_button = (Button)view.findViewById(R.id.answer_button);

        answer_button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                answer.setVisibility(View.VISIBLE);
             }
        });

        return view;
    }
}

我的主要课程，我称之为适配器

    public class MainActivity extends AppCompatActivity {

    private DbHelper dbHelper;
    List<Puzzles> puzzles = new ArrayList<Puzzles>();
    ListView listView;
    PuzzleAdapter puzzleAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        dbHelper = new DbHelper(this);
        dbHelper.createDB();

        puzzles = dbHelper.zagadki(this);
        puzzleAdapter = new PuzzleAdapter(this, puzzles);

        listView = (ListView)findViewById(R.id.listView);
        listView.setAdapter(puzzleAdapter);
    }
}

这里我从数据库中调用

    //    public List<Puzzles> zagadki(int id){
    public List<Puzzles> zagadki(Context context){
        SQLiteDatabase db = this.getReadableDatabase();
        List<Puzzles> puzzles = new ArrayList<Puzzles>();
//        String s = "select * from zagad where _id=" + id;
        String s = "select * from zagad";
        Cursor cursor = db.rawQuery(s, null);
        if (cursor.moveToFirst()){
            do {
                Puzzles puzzle = new Puzzles();
                puzzle.set_id(cursor.getInt(0));
                puzzle.setZagad(cursor.getString(1));
                puzzle.setOtveti(cursor.getString(2));
                puzzles.add(puzzle);
            }
            while (cursor.moveToNext());
        }
        db.close();
        return puzzles;
    }

Answer 1

由于您已直接查看并维护，因此会出现此问题，

所以使用holder类然后管理它检查我的下面的代码，

   public class ViewHolder {

      TextView puzzl;
      TextView answer;
      Button answer_button;
   }

   @Override
   public View getView(int i, View view, ViewGroup viewGroup) {

       View row = view;
       ViewHolder holder= null;

       if (row == null)
       {
            row = inflater.inflate(R.layout.puzzle_adapter, null);
            holder = new ViewHolder();
            holder.puzzl=(TextView)view.findViewById(R.id.puzzl);
            holder.answer=(TextView)view.findViewById(R.id.answer);
            holder.answer_button = (Button)view.findViewById(R.id.answer_button);
            row.setTag(holder);

       }
       else
       {
            holder = (AppInfoHolder)row.getTag();
       }
              holder.puzzl.setText(puzz.getZagad());
              holder.answer.setText(puzz.getOtveti());
              holder.answer_button.setTag(holder);

              holder.answer_button.setOnClickListener(new View.OnClickListener() {
                      @Override
                      public void onClick(View view) {
                         ViewHolder selectedHolder = (View Holder) view.getTag();

                         selectedHolder.answer.setVisibility(View.VISIBLE);
                       }
               });

       return row;
    }

按下Listview开头按下的每个按钮和第五个位置

1 个答案: