有人使用RecyclerView找到了一种方法来设置一个onClickListener的项目在RecyclerView? 我想设置一个监听器为每个项目的布局,但这似乎有点太麻烦了 我确信有一种方法让RecyclerView监听onClick事件,但我不能完全弄清楚。
当前回答
我有一个很好的解决方案RecyclerView的onItemClickListener的项目和子项
步骤1—创建接口
public interface OnRecyclerViewItemClickListener
{
/**
* Called when any item with in recyclerview or any item with in item
* clicked
*
* @param position
* The position of the item
* @param id
* The id of the view which is clicked with in the item or
* -1 if the item itself clicked
*/
public void onRecyclerViewItemClicked(int position, int id);
}
步骤2-然后在适配器的onBindViewHolder方法中使用它,如下所示
/**
* Custom created method for Setting the item click listener for the items and items with in items
* @param listener OnRecyclerViewItemClickListener
*/
public void setOnItemClickListener(OnRecyclerViewItemClickListener listener)
{
this.listener = listener;
}
@Override
public void onBindViewHolder(ViewHolder viewHolder, final int position)
{
// viewHolder.albumBg.setBackgroundResource(_itemData[position]
// .getImageUrl());
viewHolder.albumName.setText(arrayList.get(position).getName());
viewHolder.artistName.setText(arrayList.get(position).getArtistName());
String imgUrl = arrayList.get(position).getThumbImageUrl();
makeImageRequest(imgUrl, viewHolder);
viewHolder.parentView.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
listener.onRecyclerViewItemClicked(position, -1);
}
});
viewHolder.settingButton.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
listener.onRecyclerViewItemClicked(position, v.getId());
}
});
}
// class to hold a reference to each item of RecyclerView
public static class ViewHolder extends RecyclerView.ViewHolder
{
public TextView albumName, artistName;
public ImageView albumIcon, settingButton;
public LinearLayout parentView;
public ViewHolder(View itemLayoutView)
{
super(itemLayoutView);
// albumBg = (LinearLayout) itemLayoutView
// .findViewById(R.id.albumDlbg);
albumName = (TextView) itemLayoutView.findViewById(R.id.albumName);
artistName = (TextView) itemLayoutView
.findViewById(R.id.artistName);
albumIcon = (ImageView) itemLayoutView.findViewById(R.id.albumIcon);
parentView = (LinearLayout) itemLayoutView
.findViewById(R.id.albumDlbg);
settingButton = (ImageView) itemLayoutView
.findViewById(R.id.settingBtn);
}
}
步骤3-在活动或片段中找到并设置回收器视图,您正在使用此
recyclerView = (RecyclerView) rootview.findViewById(R.id.vmtopsongs);
lm = new LinearLayoutManager(mActivity);
lm.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setLayoutManager(lm);
recyclerView.addItemDecoration(
new HorizontalDividerItemDecoration.Builder(getActivity())
.paint(Utils.getPaint()).build());
PopularSongsadapter mAdapter = new PopularSongsadapter(gallery,
mActivity, true);
// set adapter
recyclerView.setAdapter(mAdapter);
mAdapter.setOnItemClickListener(this);
// set item animator to DefaultAnimator
recyclerView.setItemAnimator(new DefaultItemAnimator());
步骤4-最后在使用recyclerview的activity或fragment中实现接口
@Override
public void onRecyclerViewItemClicked(int position, int id)
{
if(id==-1){
Toast.makeText(mActivity, "complete item clicked", Toast.LENGTH_LONG).show();
}else{
Toast.makeText(mActivity, "setting button clicked", Toast.LENGTH_LONG).show();
}
}
更新Kotlin语言 我已经更新了kotlin的代码,其中只有整个视图有点击监听器。你可以根据上面的java代码编辑界面和代码来设置子项点击监听器。
适配器
class RecentPostsAdapter(private val list: MutableList<Post>) :
RecyclerView.Adapter<RecentPostsAdapter.ViewHolder>() {
private lateinit var onItemClickListener: OnItemClickListener
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
return ViewHolder(
LayoutInflater.from(parent.context)
.inflate(R.layout.listitem_recent_post, parent, false)
)
}
override fun getItemCount(): Int {
return list.size
}
fun setOnItemClickListener(onItemClickListener: OnItemClickListener) {
this.onItemClickListener = onItemClickListener
}
private fun getItem(position: Int): Post {
return list[position]
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.bind(getItem(position))
holder.itemView.setOnClickListener(View.OnClickListener {
onItemClickListener.onItemClick(
position
)
})
}
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
private var imageView: NetworkImageView? = null
private var tvTitle: TextView? = null
private var tvExcerpt: TextView? = null
private var htmlSpanner: HtmlSpanner = HtmlSpanner()
init {
imageView = itemView.findViewById(R.id.niv_post_image)
tvTitle = itemView.findViewById(R.id.tv_post_title)
tvExcerpt = itemView.findViewById(R.id.tv_post_excerpt)
}
fun bind(post: Post) {
tvTitle?.text = post.title
tvExcerpt?.text = htmlSpanner.fromHtml(post.excerpt)
}
}
interface OnItemClickListener {
fun onItemClick(position: Int)
}
}
活动或片段
recyclerView = view.findViewById(R.id.rvHomeRecentPosts)
recyclerView.layoutManager = LinearLayoutManager(view.context)
list = mutableListOf()
recentPostsAdapter = RecentPostsAdapter(list)
recyclerView.adapter = recentPostsAdapter
recentPostsAdapter.setOnItemClickListener(object:RecentPostsAdapter.OnItemClickListener{
override fun onItemClick(position: Int) {
(activity as MainActivity).findNavController(R.id.nav_host_fragment).navigate(R.id.action_nav_home_to_nav_post_detail)
}
})
其他回答
这对我来说很管用。将OnClickListener附加到onBindView。我真的不知道这是否会影响性能,但它似乎用很少的代码就能很好地工作。
public void onBindViewHolder(ViewHolder holder, final int position) {
holder.view.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Toast.makeText(context, "Recycle Click" + position, Toast.LENGTH_SHORT).show();
}
});
}
通常你在CardView中有多个元素,所以你需要一个布局视图来包装和组织它们。你可以添加一个OnClickListener到那个布局视图。1. 添加一个id到你的布局。在这个例子中是线性布局
<android.support.v7.widget.CardView
.....>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/card_view_linearLayout">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="name"
android:id="@+id/card_view_name" />
...
</LinearLayout>
</android.support.v7.widget.CardView>
2美元。在你的内部ViewHolder类中获取布局视图。
public static class ViewHolder extends RecyclerView.ViewHolder{
private TextView nameView;
...
private LinearLayout linearLayout;
public ViewHolder(View itemView) {
super(itemView);
nameView = (TextView)itemView.findViewById(R.id.card_view_name);
...
linearLayout = (LinearLayout)itemView.findViewById(R.id.card_view_linearLayout);
}
}
3美元。将监听器添加到onBindViewHolder中的布局中,并使用回调将数据发送到活动或片段(未测试)。
@Override
public void onBindViewHolder(TrackAdapter.ViewHolder holder, final int position) {
String str = mStringList.get(position);
holder.nameView.setText(str);
...
holder.linearLayout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
callback.itemCallback(mStringList.get(position));
}
});
}
如何使用回调是另一个故事
在kotlin中使用构造函数实现
初始化你的RecyclerView构造函数,如下所示:
class ListAdapter(
c: Context,
private var list: List<Project>,
private val itemClick: (Project) -> Unit
) : RecyclerView.Adapter<ListAdapter.ViewHolder>()
在onCreateViewHolder中使用itemClick返回:
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int):ProjectViewHolder {
val view = inflater.inflate(R.layout.list_item, parent, false)
return ViewHolder(view, itemClick)
}
你的onBindViewHolder:
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.bindProject(list[position])
}
然后用ViewHolder类创建bindProject函数。
class ViewHolder(
view: View,
private val itemClick: (Project) -> Unit
) : RecyclerView.ViewHolder(view) {
private val clientTextCount = 7
val titleTextView: TextView = view.projectTitleTextView
fun bindProject(project: Project) {
with(project) {
titleTextView.text = name
itemView.setOnClickListener { itemClick(this) }
}
}
}
最后在您的活动中用lazy初始化适配器
private val adapter: ListAdapter by lazy {
ListAdapter(this, projectList, {
// Here you can implement your onClick function.
})
}
在适配器中为RecyclerView添加新列表初始化以下方法:
fun setProjects(projects: List<Project>) {
projectList = projects
notifyDataSetChanged()
}
在你的活动中调用setProjects方法:
adapter.setProjects(projects)
就是这样。
RecyclerView没有OnClickListener,必须自己实现它。
我喜欢在适配器中添加OnItemClickListener接口,当您从ViewHolder中单击项目视图时调用onClick方法。因此,管理项目点击的职责不在ViewHolder和Adapter的范围内。将决定做什么的活动或片段
为监听器和监听器对象添加接口。
public class ItemsAdapter extends RecyclerView.Adapter<ItemsAdapter.ViewHolder> {
...
private static OnItemClickListener onItemClickListener;
...
public static interface OnItemClickListener {
public void onItemClick(View view, int position);
}
...
}
我们捕获项目根视图的单击,以及当回调触发时适配器上的onClick侦听器调用。
public class ItemsAdapter extends RecyclerView.Adapter<ItemsAdapter.ViewHolder> {
...
private static OnItemClickListener onItemClickListener;
...
public static interface OnItemClickListener {
public void onItemClick(View view, int position);
}
...
public static class ViewHolder extends RecyclerView.ViewHolder {
public ImageView imageView;
public ViewHolder(View itemRootView) {
super(itemRootView);
imageView = (ImageView) itemRootView.findViewById(R.id.itemImage);
itemRootView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
int position = ViewHolder.super.getAdapterPosition();
onItemClickListener.onItemClick(view,position);
}
});
}
}
}
由于活动或片段,片段在我们的情况下,我们分配一个监听器到适配器和onClick回调,我们将获得选定的项目的位置和打开一个详细的活动项目。
public class ItemsFragment extends Fragment {
...
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
...
((ItemsAdapter) adapter).setOnItemClickListener(new ItemsAdapter.OnItemClickListener() {
@Override
public void onItemClick(View view, int position) {
//Do something when an item has been clicked
}
});
...
}
...
}
我们可以使用Java弱引用来实现这一点。 从语义上讲,视图持有者应该响应click事件或将其委托给正确的响应器。
我们的目标:
Viewholder应该对响应事件的类一无所知,除非它实现了某个接口。 点击处理程序应该得到被点击的视图在RecyclerView中的位置。 我们应该能够辨别视图持有人中单击了哪个视图。 保持所有组件之间的松散耦合,不要造成任何保留周期。
步骤:
Create an interface to handle click responses. Implement this interface in the Activity that will handle the click. Add a member variable in the RecyclerView Adapter to hold the Weak Reference and a constructor that sets it. Do the same in the RecyclerView ViewHolder and add a member variable to keep track of position. Set your on click listeners on any view you'd like in the ViewHolder, then callback to the responder to handle them. Change your onBindViewHolder method to set the position when binding. Pass the responder down to the ViewHolder. In the responder, you can now use getId() on the view to figure out which view was clicked.
这里是一个要点,这样你就可以看到它们是如何组合在一起的: RecyclerView点击处理
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