从Android ListView中删除最后一项会导致应用程序崩溃

这就是我得到的错误：

下面是我的CartActivity的onCreate：

当购物车中有多个商品时，该功能可以完美工作。但当我试图从购物车中删除最后一项时，应用程序崩溃并抛出上述错误。有什么想法吗？我不知道怎么了

编辑：我假设有人会要求我提供CartInfoProvider的代码，因此：

public class CartInfoProvider {
    private static ArrayList<Item> cart = new ArrayList<Item>();

    public static void addToCart(Item i){
        cart.add(i);
    }

    public static void removeFromCart(Item i){
        cart.remove(i);
    }

    public static ArrayList<Item> getCart(){
        return cart;
    }
}

---

正如@commonware所说，我应该使用我的listView而不是实际的行来显示snackbar。这是因为当我删除行时，snackbar试图将自己附加到不存在的东西上，因此是空指针

---

为了解决这个问题，我只是将适配器的构造函数更改为在listview中读取，然后将其用于snackbar。干杯

为Snackbar使用一些稳定的视图，例如ListView，而不是ListView行中的一行。如果将getContext更改为McContext，会发生什么情况？@MdSufiKhan更改为McContext不起作用anything@CommonsWare谢谢这就成功了

public class CartAdapter extends ArrayAdapter<Item> implements View.OnClickListener{

    private ArrayList<Item> dataSet;
    Context mContext;

    // View lookup cache
    private static class ViewHolder {
        TextView itemTitle;
        TextView itemStore;
        TextView itemPrice;
        ImageView storeLogo;
        ImageView removeFromCart;
    }

    public CartAdapter (ArrayList<Item> data, Context context) {
        super(context, R.layout.row_cart, data);
        this.dataSet = data;
        this.mContext=context;

    }

    @Override
    public void onClick(View v) {

        int position=(Integer) v.getTag();
        Object object= getItem(position);
        final Item item=(Item)object;

        CharSequence actions[];

        final View view = v;
        switch (v.getId())
        {

            case R.id.more:
                System.out.println(item.getLink());
                Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(item.getLink()));
                mContext.startActivity(browserIntent);
                break;
        }
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // Get the data item for this position
        final Item item = getItem(position);

        // Check if an existing view is being reused, otherwise inflate the view
        ViewHolder viewHolder; // view lookup cache stored in tag

        final View result;


            viewHolder = new ViewHolder();
            LayoutInflater inflater = LayoutInflater.from(getContext());
            convertView = inflater.inflate(R.layout.row_cart, parent, false);
            viewHolder.itemTitle = (TextView) convertView.findViewById(R.id.title);
            viewHolder.itemStore = (TextView) convertView.findViewById(R.id.retailer);
            viewHolder.itemPrice = (TextView) convertView.findViewById(R.id.price);
            viewHolder.storeLogo = (ImageView) convertView.findViewById(R.id.more);
            viewHolder.removeFromCart = (ImageView) convertView.findViewById(R.id.removeCart);

            result = convertView;

            convertView.setTag(viewHolder);

        viewHolder.itemTitle.setText(item.getTitle());
        viewHolder.itemStore.setText("From " + item.getStore());
        viewHolder.itemPrice.setText("$" + item.getPrice());
        viewHolder.storeLogo.setOnClickListener(this);

        viewHolder.removeFromCart.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                CartInfoProvider.removeFromCart(item);
                MyCart.adapter.remove(item);
                MyCart.adapter.notifyDataSetChanged();

                Snackbar.make(result, "This item was removed from your cart", Snackbar.LENGTH_INDEFINITE).setAction("UNDO", new View.OnClickListener() {

                    @Override
                    public void onClick(View v) {
                        CartInfoProvider.addToCart(item);
                        MyCart.adapter.add(item);
                        MyCart.adapter.notifyDataSetChanged();
                    }

                }).show();

            }
        });


        viewHolder.storeLogo.setTag(position);

        // Return the completed view to render on screen
        return convertView;

    }
}

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_my_cart);

    ListView listView=(ListView)findViewById(R.id.cart);
    adapter= new CartAdapter(Items, this);
    listView.setAdapter(adapter);

    TextView empty = (TextView) findViewById(R.id.empty);
    listView.setEmptyView(empty);

    adapter.addAll(CartInfoProvider.getCart());
    adapter.notifyDataSetChanged();
}

public class CartInfoProvider {
    private static ArrayList<Item> cart = new ArrayList<Item>();

    public static void addToCart(Item i){
        cart.add(i);
    }

    public static void removeFromCart(Item i){
        cart.remove(i);
    }

    public static ArrayList<Item> getCart(){
        return cart;
    }
}