尽管没有任何侦听器 + imageViews，但我的 RecyclerView 仍然滞后，这是为什么呢？

Question

首先，我读过其他与我有同样问题的帖子；从我的总结来看，问题通常是因为 imageviews/pictures + listeners。但这不是我的情况。我什至没有为我的delButton 和addButton 创建听众，而且我仍然落后。

我打算做什么： https://gyazo.com/ff984e87fc11543d44d1b549147f870c

只要点击添加按钮，就会创建一个新的listRow

这是我的 RecyclerVIew 课程：

public class RecyclerAdapter extends RecyclerView.Adapter {

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.saved_list_layout, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        ((ViewHolder) holder).bindView(position);
    }

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

    public class ViewHolder extends RecyclerView.ViewHolder{
        TextView mListTextView;

        public ViewHolder(View itemView) {
            super(itemView);
            mListTextView = (TextView) itemView.findViewById(R.id.currentLIst);
        }

        public void bindView(int position){
            mListTextView.setText("List # " + position);
        }
    }

}

这是我的活动课

    public class SavedLists extends AppCompatActivity {
       // private yourListNumber[] mHoles = new yourListNumber[0];
        public static final ArrayList<ListRow> mListRow  = new ArrayList<ListRow>();
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_saved_lists);
            Button mButton = (Button) findViewById(R.id.addList);



            //RECYCLERADAPTER set-up here:
            final RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
            final RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
            recyclerView.setLayoutManager(layoutManager);
            recyclerView.setAdapter(new RecyclerAdapter());

            mButton.setOnClickListener(new View.OnClickListener(){
                @Override
                public void onClick(View v){
                    mListRow.add(new ListRow());

                    recyclerView.setLayoutManager(layoutManager);
                    recyclerView.setAdapter(new RecyclerAdapter());
                    //instead of repeating these 3 lines of code, you can use refresh
                }
            });
        }
    }

Answer 1

这是因为您总是在单击按钮时重置 recyclerView 适配器。 把onClick监听改成这样

mButton.setOnClickListener(new View.OnClickListener(){
    @Override
    public void onClick(View v){
        mListRow.add(new ListRow());

        recyclerView.notifyDataSetChanged();
    }
});

Answer 2

为什么要从 bindViewolder 调用 viewholders 方法？改成这样

public class RecyclerAdapter extends RecyclerView.Adapter {
ArrayList<ListRow> adapterListData;

 @Override
 public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

   public void RecyclerAdapter(ArrayList<ListRow> mListRow){
    adapterListData = mListRow;
   }

    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.saved_list_layout, parent, false);
    return new ViewHolder(view);
}

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
      holder.mListTextView.setText("List # " + adapterListData.get(position));

}

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

public class ViewHolder extends RecyclerView.ViewHolder{
    TextView mListTextView;

    public ViewHolder(View itemView) {
        super(itemView);
        mListTextView = (TextView) itemView.findViewById(R.id.currentLIst);
    }
}

}

并且不要在活动中设置回收器适配器两次。并在构造函数中传递您的数据并将其分配给全局变量

public class SavedLists extends AppCompatActivity {
   // private yourListNumber[] mHoles = new yourListNumber[0];
    public static final ArrayList<ListRow> mListRow  = new ArrayList<ListRow>();
     RecyclerAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_saved_lists);
        Button mButton = (Button) findViewById(R.id.addList);



        //RECYCLERADAPTER set-up here:
        final RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        final RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        mAdapter  = new RecyclerAdapter(mListRow);
        recyclerView.setAdapter(mAdapter);

        mButton.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v){
                mListRow.add(new ListRow());
                mAdapter.notifyDataSetChanged();
            }
        });
    }
}