如果我在回收站视图中有数千个项目，那么如何在每个项目上设置项目单击侦听器

Posted 2023-04-19

【中文标题】如果我在回收站视图中有数千个项目，那么如何在每个项目上设置项目单击侦听器

【英文标题】：If I Have thousands of items inside the recycler view then How can I set the item click listener on each item

【发布时间】：2021-01-31 20:53:45

【问题描述】：

recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(
            this,
            recyclerView,
            new RecyclerItemClickListener.OnItemClickListener() 
                @Override
                public void onItemClick(View view, int position) 
                    switch (position)
                        case 0:
                            Toast.makeText(MainActivity.this, "item-1 Clicked", Toast.LENGTH_SHORT).show();
                            break;
                        case 1:
                            Toast.makeText(MainActivity.this, "item-2 Clicked", Toast.LENGTH_SHORT).show();
                            break;
                        default:

                    
                

                @Override
                public void onLongItemClick(View view, int position) 
                    switch (position)
                        case 0:
                            Toast.makeText(MainActivity.this, "Get 10% Discount", Toast.LENGTH_SHORT).show();
                            break;
                        case 1:
                            Toast.makeText(MainActivity.this, "Get 20% Discount", Toast.LENGTH_SHORT).show();
                            break;
                        default:

                    
                
            
    ));

当我的回收站视图中只有两个或最多 5 个项目时，此代码是最好的。但是，如果我的回收站视图中有数千个项目，那么我该如何使用 onClickItem 或 onLongItemClick，因为使用 switch 语句将是最坏的情况。

【参考方案1】：

在你的 RecycleView 的适配器中实现一个接口

类似：

public class ProductListAdapter extends RecyclerView.Adapter<ProductListAdapter.ViewHolder> 

    private List<AccountTypeModel> mData;
    private LayoutInflater mInflater;
    private ItemClickListener mClickListener;
    Context context;


    // data is passed into the constructor
   public ProductListAdapter(Context context, List<AccountTypeModel> data, ItemClickListener mClickListener) 
        this.mInflater = LayoutInflater.from(context);
        this.mData = data;
        this.context = context;
        this.mClickListener = mClickListener;
    

    // inflates the row layout from xml when needed
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) 
        View view = mInflater.inflate(R.layout.product_list_item_design, parent, false);
        return new ViewHolder(view);
    

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, final int position) 

       AccountTypeModel currentItem = mData.get(position);
        holder.txtproductname.setText(currentItem.getAccountName());


    

    // binds the data to the TextView in each row

    // total number of rows
    @Override
    public int getItemCount() 
        return mData.size();
    


    // stores and recycles views as they are scrolled off screen
    public class ViewHolder extends `RecyclerView.ViewHolder implements View.OnClickListener` 
        TextView txtproductname;
        ConstraintLayout relativeLayout;

        ViewHolder(View itemView) 
            super(itemView);
            itemView.setOnClickListener(this);
            txtproductname = itemView.findViewById(R.id.txtproductname);
            relativeLayout = itemView.findViewById(R.id.myItemLayout);

        


    @Override
        public void onClick(View view) 
            if (mClickListener != null) 
                mClickListener.onItemClick(view, getAdapterPosition(), mData.get(getAdapterPosition()).getAccountID());
    
            
            notifyDataSetChanged();

        
    
    // convenience method for getting data at click position
    public String getItem(int id) 
        return mData.get(id).getAccountID();
    
    // allows clicks events to be caught
    public void setClickListener(ItemClickListener itemClickListener) 
       this.mClickListener = itemClickListener;
    
      // parent activity will implement this method to respond to click events
        public interface ItemClickListener 
            void onItemClick(View view, int position, String name);
        

然后在您的 Activity 类中实现 onClick。