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?
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;
}
}
}
如果您有一个pojo列表，并且希望从适配器外部单击检索一个pojo，那么这里有一种非常容易实现它的方法。
在你的适配器中，为点击事件创建一个监听器和一个方法来设置它:
public class MyAdapter extends RecyclerView.Adapter<SitesListAdapter.ViewHolder> {
...
private List<MyPojo> mMyPojos;
private static OnItemClickListener mOnItemClickListener;
...
public interface OnItemClickListener {
public void onItemClick(MyPojo pojo);
}
...
public void setOnItemClickListener(OnItemClickListener onItemClickListener){
mOnItemClickListener = onItemClickListener;
}
...
}
在你的ViewHolder中，实现onClickListener并创建一个类成员来临时存储视图所呈现的POJO(这是一个例子，创建一个setter会更好):
public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public MyPojo mCurrentPojo;
...
public ViewHolder(View view) {
super(v);
...
view.setOnClickListener(this); //You could set this on part of the layout too
}
...
@Override
public void onClick(View view) {
if(mOnItemClickListener != null && mCurrentPojo != null){
mOnItemClickListener.onItemClick(mCurrentPojo);
}
}
回到你的适配器，当ViewHolder被绑定时设置当前POJO(如果当前视图没有，则设置为null):
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
final MyPojo currentPojo = mMyPojos.get(position);
holder.mCurrentPojo = currentPojo;
...
就是这样，现在你可以在你的fragment/activity中这样使用它:
mMyAdapter.setOnItemClickListener(new mMyAdapter.OnItemClickListener() {
@Override
public void onItemClick(MyPojo pojo) {
//Do whatever you want with your pojo here
}
});
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);
