当我单击按钮加载数据时出现运行时异常答案

【问题标题】：runtime exception when i click the button to load data当我单击按钮加载数据时出现运行时异常
【发布时间】：2019-06-16 17:04:17
【问题描述】：

我想从SQLite 数据库中检索数据并将其显示在RecyclerView 中，但它显示错误

((适配器类))

public class myAdapert extends RecyclerView.Adapter<myAdapert.myViewHolder> {
ArrayList<Model_class> modelClassArrayList;

public myAdapert(ArrayList<Model_class> modelClassArrayList) {
    this.modelClassArrayList = modelClassArrayList;
}

@NonNull
@Override
public myViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
    View customView = LayoutInflater.from(viewGroup.getContext())
            .inflate(R.layout.custom_row,viewGroup,false);
    myViewHolder myviewHolder = new myViewHolder(customView);
    return myviewHolder;
}

@Override
public void onBindViewHolder(@NonNull myViewHolder myViewHolder, int i) {
    Model_class model_class = modelClassArrayList.get(i);
    myViewHolder.author.setText(model_class.getAuthor());
    myViewHolder.title.setText(model_class.getTitle());
    myViewHolder.cost.setText(model_class.getCost());
    myViewHolder.quantity.setText(model_class.getQuantity());

}

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

public class myViewHolder extends RecyclerView.ViewHolder {
    TextView author,title;
    TextView cost,quantity;
    public myViewHolder(@NonNull View itemView) {
        super(itemView);
        author = itemView.findViewById(R.id.authortxt);
        title = itemView.findViewById(R.id.titleTxt);
        cost = itemView.findViewById(R.id.costTxt);
        quantity = itemView.findViewById(R.id.quantityTxt);
    }
}

【问题讨论】：

你的适配器的第 34 行是什么？

标签： android sqlite android-recyclerview

【解决方案1】：

由于成本和数量都是数字，我想您应该将其显式转换为字符串，以防止资源管理器加载可绘制对象：

    myViewHolder.cost.setText(String.valueOf(model_class.getCost()));
    myViewHolder.quantity.setText(String.valueOf(model_class.getQuantity()));

【讨论】：