android - notifyDataSetChange 不适用于自定义适配器

Question

当我重新填充 ListView 时，我会从 Adapter 调用特定方法。

问题:

当我从我的 Adapter 调用 updateReceiptsList 时，数据被刷新，但我的 ListView 没有反射(reflect)更改。

问题:

为什么我调用notifyDataSetChanged时我的ListView没有显示新数据？

适配器:

public class ReceiptListAdapter extends BaseAdapter {

    public List<Receipt> receiptlist;
    private Context context;
    private LayoutInflater inflater;
    private DateHelpers dateH;

    public ReceiptListAdapter(Activity activity, Context mcontext, List<Receipt> rl) {
        context = mcontext;
        receiptlist = rl;
        Collections.reverse(receiptlist);
        inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        dateH = new DateHelpers();
    }

    @Override
    public int getCount() {
        try {
            int size = receiptlist.size();
            return size;
        } catch(NullPointerException ex) {
            return 0;
        }
    }

    public void updateReceiptsList(List<Receipt> newlist) {
        receiptlist = newlist;
        this.notifyDataSetChanged();
    }

    @Override
    public Receipt getItem(int i) {
        return receiptlist.get(i);
    }

    @Override
    public long getItemId(int i) {
        return receiptlist.get(i).getReceiptId() ;
    }

    private String getPuntenString(Receipt r) {
        if(r.getPoints().equals("1")) {
            return "1 punt";
        }
        return r.getPoints()+" punten";
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View vi=convertView;

        final Receipt receipt = receiptlist.get(position);
        ReceiptViewHolder receiptviewholder;
        Typeface tf_hn = Typeface.createFromAsset(context.getAssets(), "helveticaneue.ttf");        
        Typeface tf_hn_bold = Typeface.createFromAsset(context.getAssets(), "helveticaneuebd.ttf");

        if (vi == null) { //convertview==null
            receiptviewholder = new ReceiptViewHolder();
            vi = inflater.inflate(R.layout.view_listitem_receipt, null);
            vi.setOnClickListener(null);
            vi.setOnLongClickListener(null);
            vi.setLongClickable(false);
            receiptviewholder.shop = (TextView) vi.findViewById(R.id.tv_listitemreceipt_shop);
            receiptviewholder.date = (TextView) vi.findViewById(R.id.tv_listitemreceipt_date);
            receiptviewholder.price = (TextView) vi.findViewById(R.id.tv_listitemreceipt_price);
            receiptviewholder.points = (TextView) vi.findViewById(R.id.tv_listitemreceipt_points);
            receiptviewholder.shop.setTypeface(tf_hn_bold);
            receiptviewholder.price.setTypeface(tf_hn_bold);
            vi.setTag(receiptviewholder);
        }else{//convertview is not null
            receiptviewholder = (ReceiptViewHolder)vi.getTag();
        }

        receiptviewholder.shop.setText(receipt.getShop());
        receiptviewholder.date.setText(dateH.timestampToDateString(Long.parseLong(receipt.getPurchaseDate())));
        receiptviewholder.price.setText("€ "+receipt.getPrice());
        receiptviewholder.points.setText(getPuntenString(receipt));

        vi.setClickable(false);
        return vi;
    }

    public static class ReceiptViewHolder {
        public TextView shop;
        public TextView date;
        public TextView price;
        public TextView points;
    }

    public Object getFilter() {
        // XXX Auto-generated method stub
        return null;
    }

}

--编辑:

找到解决方法

只是为了有一些我现在做的功能代码:

listview.setAdapter( new ReceiptListAdapter(activity,mcontext, -new dataset-);

有效，但不是它应该如何工作。

Answer 1

改变你的方法

public void updateReceiptsList(List<Receipt> newlist) {
    receiptlist = newlist;
    this.notifyDataSetChanged();
}

到

public void updateReceiptsList(List<Receipt> newlist) {
    receiptlist.clear();
    receiptlist.addAll(newlist);
    this.notifyDataSetChanged();
}

因此，您在适配器中保留与 DataSet 相同的对象。