如何从适配器获取List size()并从Recycler Adapter本身更新Activity UI? [英] How to get the List size() from adapter and update Activity UI from recycler Adapter itself?

问题描述

我的适配器呼叫中有一个删除按钮，当我按下删除按钮时，我想

I have a delete button in my adapter call and when i press the delete button i want to

1.从列表中删除值，然后

2.在主要活动中更新列表的大小

和. 尝试在我在此处 引用的界面上 ，但它不起作用，我很困惑.

and . Have tried using Interface where i referred here but it's not working and i am so confused.

任何人都可以为我提供最好的方法

So can any one provide me an best way

我的适配器代码:

@Override
public void onBindViewHolder(final AddLineItem_Adapter.ViewHolder holder, final int position) {
    final AddLineItem_ListView addLineItem_listView = addLineItem_listViews.get(position);

    holder.tv_OrderID.setText(addLineItem_listView.getItemID());
    holder.tv_ProductName.setText(addLineItem_listView.getProductName());
    holder.tv_Quantity.setText(addLineItem_listView.getQuantity());
    holder.tv_UnitPrice.setText(addLineItem_listView.getUnitPrice());
    holder.tv_TotalAmount.setText(addLineItem_listView.getTotalAmount());

    holder.btn_Delete.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            addLineItem_listViews.remove(position);
            notifyDataSetChanged();
        }
    });
}

我想更新TextView中主要活动的addLineItem_listView大小.

I want to update the addLineItem_listView size on the main activity in TextView.

推荐答案

• 创建界面.
• 将其传递给适配器.
• 删除后调用界面函数(提供列表的大小)

创建界面

public interface ShowDeleted {

void showDeleted(int size);

}

在这样的活动中匿名初始化界面

ShowDeleted showDeleted = new ShowDeleted() {
    @Override
    public void showDeleted(int size) {
         // show the changed list size or update UI
    }
};

将界面传递给recyclerAdapter

YourAdapter youradpter = new YourAdpater(context,list,showDeleted );

像这样初始化recyclerAdapter的构造函数:-

   public YourAdapter(Context context, YourList yourList, ShowDeleted 
                                                           showDeleted)
     {
            }

holder.onClick执行此操作

holder.btn_Delete.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        addLineItem_listViews.remove(position);
        notifyDataSetChanged();
        this.showDeleted.showDeleted(addLineItem_listViews.size());
    }
});

这篇关于如何从适配器获取List size()并从Recycler Adapter本身更新Activity UI?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！