Question

我在处理ListView的重复方面遇到问题。正如您在屏幕截图上所看到的，我有一个spinner，其中包含所有需要的项目。当用户单击该特定项目时，它将添加到我的ListView上。但是问题是数据被复制了。

这是图片：

场景： 假装这是列表项

A

B

C

D

如果我单击“ A”。它将添加到我的ListView上对吗？然后点击“ B”。因此，ListView上的数据是：A和B。如果再次单击“ A”，它将在ListView上添加当前项。我需要限制当前正在发生的重复。

这是我点击Spinner

时的代码

 public void addViolationListenerOnSpinnerItemSelection() {
    spinner_violation.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override

        public void onItemSelected(AdapterView<?> parent2, View view, int position2, long id) {

            if (position2 != 0) {

                vio_val = String.valueOf(spinner_violation.getSelectedItem());
                adapter = new ViolationAdapter(getContext(), generateData());

                lv_inspector_violation.setAdapter(adapter);
                adapter.notifyDataSetChanged();
            }

        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });
}

这是generateData()

private ArrayList<InspectorViolationItem> generateData() {
    items.add(new InspectorViolationItem(emp_val, vio_val));
    HashSet<InspectorViolationItem> hs = new HashSet<>();
    hs.addAll(items);
    items.clear();
    items.addAll(hs);
    return items;
}

InspectorViolationItem只是一个Getters和Setters，所以我认为不需要发布代码。

最后，这是我使用的适配器：

public class ViolationAdapter extends ArrayAdapter<InspectorViolationItem> {

Context c;

private ArrayList<InspectorViolationItem> itemsArrayList;


public ViolationAdapter( Context context, ArrayList<InspectorViolationItem> itemsArrayList) {
    super(context, R.layout.item_violation, itemsArrayList);
    this.c = context;
    this.itemsArrayList = itemsArrayList;

}


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

    // 1. Create inflater
    LayoutInflater inflater = (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    // 2. Get rowView from inflater
    View rowView = inflater.inflate(R.layout.item_violation, parent, false);

    // 3. Get the two text view from the rowView
    TextView labelView = (TextView) rowView.findViewById(R.id.txt_violation_employee);
    TextView valueView = (TextView) rowView.findViewById(R.id.txt_violation_violation);



    // 4. Set the text for textView
    labelView.setText(itemsArrayList.get(position).getEmployee());
    valueView.setText(itemsArrayList.get(position).getViolation());

    // 5. retrn rowView
    return rowView;
    }

}

Answer 1

我通过将所选项目放在ArrayList<>上

并进行如下验证：

 if (position2 != 0) {
                vio_val = String.valueOf(spinner_violation.getSelectedItem());

                if (!violationHolder.contains(vio_val)) {
                    adapter = new ViolationAdapter(getContext(), generateData());
                    violationHolder.add(vio_val);

                    lv_inspector_violation.setAdapter(adapter);
                    adapter.notifyDataSetChanged();
                } else {
                    Toast toast = Toast.makeText(getContext(), "Duplicate Violation.", Toast.LENGTH_SHORT);
                    toast.setGravity(Gravity.CENTER, 0, 0);
                    toast.show();
                }
            }

感谢您的帮助

限制listView项目复制

1 个答案: