java.lang.nullpointerexception:尝试在空对象引用上调用虚拟方法应用程序在运行时崩溃

7vux5j2d  于 2021-07-08  发布在  Java
关注(0)|答案(2)|浏览(391)

需要有关此错误日志的帮助。正在尝试创建一个食品配送应用程序,下面是androidstudio上应用程序的源代码。每次我运行应用程序时,应用程序都会不断崩溃

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
        at com.example.swiftbites.Adapters.OrdersAdapter.onBindViewHolder(OrdersAdapter.java:43)
        at com.example.swiftbites.Adapters.OrdersAdapter.onBindViewHolder(OrdersAdapter.java:19)

代码:
ordersadapter.java文件

package com.example.swiftbites.Adapters;

import ...

public class OrdersAdapter extends RecyclerView.Adapter<OrdersAdapter.viewHolder>{

    ArrayList<OrdersModel> list;
    Context context;

    public OrdersAdapter(ArrayList<OrdersModel> list, Context context) {
        this.list = list;
        this.context = context;
    }

    @NonNull
    @Override
    public viewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(context).inflate(R.layout.order_sample, parent, false);
        return new viewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull viewHolder holder, int position) {

        final OrdersModel model = list.get(position);
        holder.orderImage.setImageResource(model.getOrderImage());
        holder.soldItemName.setText(model.getSoldItemName());
        holder.orderNumber.setText(model.getOrderNumber());
        holder.price.setText(model.getPrice());
    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    public class viewHolder extends RecyclerView.ViewHolder {
        ImageView orderImage;
        TextView soldItemName, orderNumber, price;

        public viewHolder(@NonNull View itemView) {
            super(itemView);
            orderImage = itemView.findViewById(R.id.orderImage);
            soldItemName = itemView.findViewById(R.id.orderItemName);
            orderNumber = itemView.findViewById(R.id.orderNumber);
            price = itemView.findViewById(R.id.orderPrice);
        }
    }
}
dy1byipe

dy1byipe1#

在适配器中,您将获得名为orderprice的id,但在已定义的xml中,没有定义名为this的id。这就是为什么你会崩溃。您需要将textview6重命名为orderprice,或者您可以将适配器中的orderprice更改为textview6,如下所示
改变这个

price = itemView.findViewById(R.id.orderPrice);

为了这个

price = itemView.findViewById(R.id.textView6);
xxslljrj

xxslljrj2#

检查您的textview id,它是错误的,这就是为什么android studio会产生空指针异常,因为您在另一个textview上设置了settext(),而不是这个。

相关问题