我正在探索RecyclerView,我很惊讶地看到,RecyclerView没有onItemClickListener()。

我有两个问题。

主要问题

我想知道为什么谷歌删除onItemClickListener()?

是否存在性能问题或其他问题?

次要的问题

我解决了我的问题写onClick在我的RecyclerView。适配器:

public static class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {

    public TextView txtViewTitle;
    public ImageView imgViewIcon;

    public ViewHolder(View itemLayoutView) {
        super(itemLayoutView);
        txtViewTitle = (TextView) itemLayoutView.findViewById(R.id.item_title);
        imgViewIcon = (ImageView) itemLayoutView.findViewById(R.id.item_icon);
    }

    @Override
    public void onClick(View v) {

    }
}

这样可以吗/有更好的办法吗?


当前回答

伙计们,在你们的主要活动中使用这个代码。非常有效的方法

RecyclerView recyclerView = (RecyclerView) findViewById(R.id.users_list);            
UsersAdapter adapter = new UsersAdapter(users, this);
recyclerView.setAdapter(adapter);
adapter.setOnCardClickListner(this);

下面是适配器类。

public class UsersAdapter extends RecyclerView.Adapter<UsersAdapter.UserViewHolder> {
        private ArrayList<User> mDataSet;
        OnCardClickListner onCardClickListner;


        public UsersAdapter(ArrayList<User> mDataSet) {
            this.mDataSet = mDataSet;
        }

        @Override
        public UserViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.user_row_layout, parent, false);
            UserViewHolder userViewHolder = new UserViewHolder(v);
            return userViewHolder;
        }

        @Override
        public void onBindViewHolder(UserViewHolder holder, final int position) {
            holder.name_entry.setText(mDataSet.get(position).getUser_name());
            holder.cardView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    onCardClickListner.OnCardClicked(v, position);
                }
            });
        }

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

        @Override
        public void onAttachedToRecyclerView(RecyclerView recyclerView) {
            super.onAttachedToRecyclerView(recyclerView);
        }


        public static class UserViewHolder extends RecyclerView.ViewHolder {
            CardView cardView;
            TextView name_entry;

            public UserViewHolder(View itemView) {
                super(itemView);
                cardView = (CardView) itemView.findViewById(R.id.user_layout);
                name_entry = (TextView) itemView.findViewById(R.id.name_entry);
             }
        }

        public interface OnCardClickListner {
            void OnCardClicked(View view, int position);
        }

        public void setOnCardClickListner(OnCardClickListner onCardClickListner) {
            this.onCardClickListner = onCardClickListner;
        }
    }

在此之后,您将在您的活动中获得这个覆盖方法。

@Override
    public void OnCardClicked(View view, int position) {
        Log.d("OnClick", "Card Position" + position);
    }

其他回答

感谢@marmor,我更新了我的答案。

我认为在ViewHolder类构造函数中处理onClick()并通过OnItemClickListener接口将其传递给父类是一个很好的解决方案。

MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder>{

private LayoutInflater layoutInflater;
private List<MyObject> items;
private AdapterView.OnItemClickListener onItemClickListener;

public MyAdapter(Context context, AdapterView.OnItemClickListener onItemClickListener, List<MyObject> items) {
    layoutInflater = LayoutInflater.from(context);
    this.items = items;
    this.onItemClickListener = onItemClickListener;
}

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = layoutInflater.inflate(R.layout.my_row_layout, parent, false);
    return new ViewHolder(view);
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    MyObject item = items.get(position);
}

public MyObject getItem(int position) {
    return items.get(position);
}


class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    private TextView title;
    private ImageView avatar;

    public ViewHolder(View itemView) {
        super(itemView);
        title = itemView.findViewById(R.id.title);
        avatar = itemView.findViewById(R.id.avatar);

        title.setOnClickListener(this);
        avatar.setOnClickListener(this);
        itemView.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        //passing the clicked position to the parent class
        onItemClickListener.onItemClick(null, view, getAdapterPosition(), view.getId());
    }
}
}

适配器在其他类中的使用:

MyFragment.java

public class MyFragment extends Fragment implements AdapterView.OnItemClickListener {

private RecyclerView recycleview;
private MyAdapter adapter;

    .
    .
    .

private void init(Context context) {
    //passing this fragment as OnItemClickListener to the adapter
    adapter = new MyAdapter(context, this, items);
    recycleview.setAdapter(adapter);
}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    //you can get the clicked item from the adapter using its position
    MyObject item = adapter.getItem(position);

    //you can also find out which view was clicked
    switch (view.getId()) {
        case R.id.title:
            //title view was clicked
            break;
        case R.id.avatar:
            //avatar view was clicked
            break;
        default:
            //the whole row was clicked
    }
}

}

在这里,你可以处理多个点击看到下面的代码,这是非常有效的

    public class RVNewsAdapter extends RecyclerView.Adapter<RVNewsAdapter.FeedHolder> {

    private Context context;
    List<News> newsList;
    // Allows to remember the last item shown on screen
    private int lastPosition = -1;

    public RVNewsAdapter(List<News> newsList, Context context) {
        this.newsList = newsList;
        this.context = context;
    }

    public static class FeedHolder extends RecyclerView.ViewHolder implements OnClickListener {

        ImageView img_main;
        TextView tv_title;
        Button bt_facebook, bt_twitter, bt_share, bt_comment;


        public FeedHolder(View itemView) {
            super(itemView);

            img_main = (ImageView) itemView.findViewById(R.id.img_main);
            tv_title = (TextView) itemView.findViewById(R.id.tv_title);
            bt_facebook = (Button) itemView.findViewById(R.id.bt_facebook);
            bt_twitter = (Button) itemView.findViewById(R.id.bt_twitter);
            bt_share = (Button) itemView.findViewById(R.id.bt_share);
            bt_comment = (Button) itemView.findViewById(R.id.bt_comment);

            img_main.setOnClickListener(this);
            bt_facebook.setOnClickListener(this);
            bt_twitter.setOnClickListener(this);
            bt_comment.setOnClickListener(this);
            bt_share.setOnClickListener(this);

        }


        @Override
        public void onClick(View v) {

            if (v.getId() == bt_comment.getId()) {

                Toast.makeText(v.getContext(), "Comment  " , Toast.LENGTH_SHORT).show();

            } else if (v.getId() == bt_facebook.getId()) {

                Toast.makeText(v.getContext(), "Facebook  " , Toast.LENGTH_SHORT).show();

            } else if (v.getId() == bt_twitter.getId()) {

                Toast.makeText(v.getContext(), "Twitter  " , Toast.LENGTH_SHORT).show();

            } else if (v.getId() == bt_share.getId()) {

                Toast.makeText(v.getContext(), "share  " , Toast.LENGTH_SHORT).show();

            }
            else {
                Toast.makeText(v.getContext(), "ROW PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
            }
        }
    }

    @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
    }

    @Override
    public FeedHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.feed_row, parent, false);
        FeedHolder feedHolder = new FeedHolder(view);

        return feedHolder;
    }

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

        holder.tv_title.setText(newsList.get(position).getTitle());


        // Here you apply the animation when the view is bound
        setAnimation(holder.img_main, position);
    }

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


    /**
     * Here is the key method to apply the animation
     */
    private void setAnimation(View viewToAnimate, int position) {
        // If the bound view wasn't previously displayed on screen, it's animated
        if (position > lastPosition) {
            Animation animation = AnimationUtils.loadAnimation(context, android.R.anim.slide_in_left);
            viewToAnimate.startAnimation(animation);
            lastPosition = position;
        }
    }


}

而不是实现接口视图。OnClickListener内部视图持有人或创建和接口和实现接口在您的活动.. 我使用这段代码简单的OnClickListener实现。

public static class SimpleStringRecyclerViewAdapter
            extends RecyclerView.Adapter<SimpleStringRecyclerViewAdapter.ViewHolder> {

        // Your initializations goes here...
        private List<String> mValues;

        public static class ViewHolder extends RecyclerView.ViewHolder {

            //create a variable mView
            public final View mView;

            /*All your row widgets goes here
            public final ImageView mImageView;
            public final TextView mTextView;*/

            public ViewHolder(View view) {
                super(view);
                //Initialize it here
                mView = view;

                /* your row widgets initializations goes here
                mImageView = (ImageView) view.findViewById(R.id.avatar);
                mTextView = (TextView) view.findViewById(android.R.id.text1);*/
            }
        }

        public String getValueAt(int position) {
            return mValues.get(position);
        }

        public SimpleStringRecyclerViewAdapter(Context context, List<String> items) {

            mBackground = mTypedValue.resourceId;
            mValues = items;
        }

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

        @Override
        public void onBindViewHolder(final ViewHolder holder, int position) {
            holder.mBoundString = mValues.get(position);
            holder.mTextView.setText(mValues.get(position));

            //Here it is simply write onItemClick listener here
            holder.mView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Context context = v.getContext();
                    Intent intent = new Intent(context, ExampleActivity.class);

                    context.startActivity(intent);
                }
            });
        }

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

RecyclerView是如何不同于Listview?

一个区别是有一个LayoutManager类和RecyclerView,通过它你可以像-一样管理你的RecyclerView

水平或垂直滚动线性layoutmanager GridLayout by GridLayoutManager 交错网格布局由StaggeredGridLayoutManager

就像水平滚动的RecyclerView-

LinearLayoutManager llm = new LinearLayoutManager(context);
llm.setOrientation(LinearLayoutManager.HORIZONTAL);
recyclerView.setLayoutManager(llm);

这招对我很管用:

@Override
public void onBindViewHolder(PlacesListViewAdapter.ViewHolder holder, int position) {
    ----
    ----
    ----
    // Set setOnClickListener(holder);
}


@Override
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    ----
    ----
    ----

    @Override
    public void onClick(View view) {
        // Use to get the item clicked getAdapterPosition()
    }
}