复选框取消选中并且列表视图的行值未更新

Question

看起来很困惑，我也对正在发生的事情感到困惑。我有一个应用程序，其中有一个显示值的列表视图，当按下一行时，该行的第三个值将显示一个值。

例如：第三个值是 30，当它被按下时，它应该除以 6，所以答案应该是 5。

但是当我在列表视图中滚动时，复选框变为未选中状态，third value of the row 恢复为旧值(30).

有什么方法可以防止复选框被选中并在单击时保留行的值？

这是我的代码的 sn-p。

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @RequiresApi(api = Build.VERSION_CODES.N)
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            CheckBox checkBox = (CheckBox)view.findViewById(R.id.checkmark);
            TextView tv3 = (TextView)view.findViewById(R.id.tx_counter);
            EditText editText = (EditText)findViewById(R.id.editText3);
            String yy = editText.getText().toString().trim();
            String shitts = listView.getItemAtPosition(position).toString();
            try {
                String[] a = shitts.split(", ");
                String[] b = a[1].split("=");
                String[] sep = a[0].split("=");
                String betnumber = sep[1];
                String betamount= b[1];
                if (view != null) {
                    checkBox.setChecked(!checkBox.isChecked());
                    if(checkBox.isChecked()){
                        //sort number
                        final String sorted = betnumber.chars().sorted().mapToObj(c -> Character.valueOf((char)c).toString()).collect(Collectors.joining());
                        System.out.println(sorted);
                        //check if double digit
                        Boolean checker = doubleChecker(sorted);
                        if (checker == true){
                            Toast.makeText(getApplicationContext(),"DOUBLE DIGIT", LENGTH_SHORT).show();
                            int answer = Integer.parseInt(betamount) / 3;
                            tv3.setText(String.valueOf(answer));
                        }else{
                            Toast.makeText(getApplicationContext(),"NOT DOUBLE DIGIT", LENGTH_SHORT).show();
                            int answer;
                            if(yy.equals("")){
                                 answer = Integer.parseInt(betamount) / 6;
                                 tv3.setText(String.valueOf(answer));
                            }else{
                                answer = (Integer.parseInt(betamount) - Integer.parseInt(yy)) / 6;
                                tv3.setText(String.valueOf(answer));
                            }
                        }
                        //TODO save to array to send

                    }else{
                        //TODO mistake RETURN tv3 to old value
                    }
                }
            }catch (Exception e){
            }
        }
    });

这是我的适配器。

    class MyAdapter extends BaseAdapter {
    private ArrayList<HashMap<String, String>> mData;
    public MyAdapter(ArrayList<HashMap<String, String>> mData2) {
        this.mData = mData2;
    }
    @Override
    public int getCount() {
        return mData.size();
    }
    @Override
    public Object getItem(int i) {
        return this.mData.get(i);
    }
    @Override
    public long getItemId(int i) {
        return i;
    }
    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        view = getLayoutInflater().inflate(R.layout.row_layout, null);
        TextView tx_number = (TextView) view.findViewById(R.id.tx_number);
        TextView tx_amount = (TextView) view.findViewById(R.id.tx_amount);
        TextView tx_counter = (TextView) view.findViewById(R.id.tx_counter);
        String betid = mData.get(i).get("betid");
        if(betid!=null){
            String betnumber = mData.get(i).get("betnumber");
            String amountTarget = mData.get(i).get("amountTarget");
            String amountRamble = mData.get(i).get("amountRamble");
            tx_number.setText(betnumber);
            tx_amount.setText(amountTarget);
            tx_counter.setText(amountRamble);
        }
        return view;
    }
}

Answer 1

将您的适配器代码替换为：

public class MyAdapter extends BaseAdapter {
    private ArrayList<HashMap<String, String>> mData;

    public MyAdapter(ArrayList<HashMap<String, String>> mData2) {
        this.mData = mData2;
    }

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

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

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

    @Override
    public View getView(int i, View convertView, ViewGroup viewGroup) {
        View mView = convertView;

        String betid = mData.get(i).get("betid");

        ViewHolder holder ;

        if (mView == null) {
            Context context = viewGroup.getContext();
            LayoutInflater inflater = LayoutInflater.from(context);
            mView = inflater.inflate(R.layout.row_layout, null,false);
            holder = new ViewHolder();
            holder.tx_number = (TextView) mView.findViewById(R.id.tx_number);
            holder.tx_amount = (TextView) mView.findViewById(R.id.tx_amount);
            holder.tx_counter = (TextView) mView.findViewById(R.id.tx_counter);
            mView.setTag(holder);
        } else {
            holder = (ViewHolder) mView.getTag();
        }


        if (betid != null) {
            String betnumber = mData.get(i).get("betnumber");
            String amountTarget = mData.get(i).get("amountTarget");
            String amountRamble = mData.get(i).get("amountRamble");
            holder.tx_number.setText(betnumber);
            holder.tx_amount.setText(amountTarget);
            holder.tx_counter.setText(amountRamble);
        }
        return mView;
    }

    private static class ViewHolder {
        TextView tx_number;
        TextView tx_amount;
        TextView tx_counter;
    }
}

我用ViewHolder 添加了新代码。