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
这里有一个策略,它给出了一个类似于ListView实现的结果,因为你可以在活动或片段级别而不是适配器或ViewHolder级别定义侦听器。它还定义了一些抽象类,这些抽象类负责适配器和持有者的大量样板工作。
抽象类
首先,定义一个抽象Holder,它扩展了RecyclerView。并定义了一个泛型数据类型T,用于将数据绑定到视图。bindViews方法将由一个子类实现,用于将数据映射到视图。
public abstract class Holder<T> extends RecyclerView.ViewHolder {
T data;
public Holder(View itemView) {
super(itemView);
}
public void bindData(T data){
this.data = data;
bindViews(data);
}
abstract protected void bindViews(T data);
}
同样,创建一个抽象适配器,扩展RecyclerView.Adapter<Holder<T>>。这定义了3个接口方法中的2个,子类将需要实现最后一个onViewHolderCreated方法。
public abstract class Adapter<T> extends RecyclerView.Adapter<Holder<T>> {
List<T> list = new ArrayList<>();
@Override
public void onBindViewHolder(Holder<T> holder, int position) {
holder.bindData(list.get(position));
}
@Override
public int getItemCount() {
return list.size();
}
public T getItem(int adapterPosition){
return list.get(adapterPosition);
}
}
具体类
现在创建一个扩展Holder的新具体类。该方法只需定义视图并处理绑定。这里我使用ButterKnife库,但请随意使用itemView.findViewById(…)方法代替。
public class PersonHolder extends Holder<Person>{
@Bind(R.id.firstname) TextView firstname;
@Bind(R.id.lastname) TextView lastname;
public PersonHolder(View view){
super(view);
ButterKnife.bind(this, view);
}
@Override
protected void bindViews(Person person) {
firstname.setText(person.firstname);
lastname.setText(person.lastname);
}
}
最后,在持有RecyclerView的Activity或Fragment类中,你会有这样的代码:
// Create adapter, this happens in parent Activity or Fragment of RecyclerView
adapter = new Adapter<Person>(){
@Override
public PersonHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.layout_person_view, parent, false);
PersonHolder holder = new PersonHolder(v);
v.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View v) {
int itemPos = holder.getAdapterPosition();
Person person = getItem(itemPos);
// do something with person
EventBus.getDefault().postSticky(new PersonClickedEvent(itemPos, person));
}
});
return holder;
}
};
其他回答
对我来说,最干净的方法就是这个。
适配器的构造函数
private class EnvironmentTypeRecyclerViewAdapter extends RecyclerView.Adapter<EnvironmentTypeRecyclerViewAdapter.ViewHolder>
{
private final EnvironmentTypeRecyclerViewAdapterListener mEnvironmentTypeRecyclerViewAdapterListener;
private List<Environment> mEnvironmentsData;
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener
{
public ViewHolder(View v)
{
super(v);
v.setOnClickListener(this);
}
@Override
public void onClick(View v)
{
Environment environment = mEnvironmentsData.get(getAdapterPosition());
if (mEnvironmentTypeRecyclerViewAdapterListener != null && environment != null) {
mEnvironmentTypeRecyclerViewAdapterListener.onListItemSelected(environment);
}
}
public EnvironmentTypeRecyclerViewAdapter(List<SmallCellEnvironment> environments, EnvironmentTypeRecyclerViewAdapterListener environmentTypeRecyclerViewAdapterListener)
{
mEnvironmentTypeRecyclerViewAdapterListener = environmentTypeRecyclerViewAdapterListener;
mEnvironmentsData = environments;
}
}
链接接口
private interface EnvironmentTypeRecyclerViewAdapterListener
{
void onListItemSelected(Environment environment);
}
根据Yigit Boyar的说法,在RecyclerView上注册点击的最好方法是在ViewHolder的创建中定义点击,而不是仅仅为onBindViewHolder绑定的每个项目创建一个新的onClickListener
例子:
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): BaseViewHolder<*> {
val itemBinding = LayoutInflater.from(context).inflate(R.layout.my_layout, parent, false)
val vh = MainViewHolder (itemBinding)
vh.itemView.setOnClickListener {
val pos = vh.adapterPosition
if(pos != NO_POSITION){
itemClickLister.onCocktailClick(myList[pos],pos)
}
}
return vh
}
我是这样做的,没有不必要的类、检测器等。适配器中的简单代码。特别是针对longClick的更好解决方案。
public class PasswordAdapter extends RecyclerView.Adapter<PasswordAdapter.ViewHolder> {
private final ClickListener clickListener;
public PasswordAdapter(ClickListener clickListener) {
this.clickListener = clickListener;
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener, View.OnLongClickListener {
TextView name;
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
itemView.setOnLongClickListener(this);
name = (TextView) itemView.findViewById(R.id.card_name);
}
@Override
public void onClick(View v) {
int position = getBindingAdapterPosition();
if (position >= 0) {
clickListener.onItemClick(position, v);
}
}
@Override
public boolean onLongClick(View v) {
int position = getBindingAdapterPosition();
if (position >= 0) {
clickListener.onItemLongClick(position, v);
return true;
}
return false;
}
}
public interface ClickListener {
void onItemClick(int position, View v);
void onItemLongClick(int position, View v);
}
}
然后在片段或活动中,点击:
PasswordAdapter mAdapter = new PasswordAdapter(
new PasswordAdapter.ClickListener() {
@Override
public void onItemClick(int position, View v) {
Log.d(TAG, "onItemClick position: " + position);
}
@Override
public void onItemLongClick(int position, View v) {
Log.d(TAG, "onItemLongClick pos = " + position);
}
}
);
你可以实现View。OnClickListener到你的ViewHolder类
public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public Item item
@InjectView(R.id.tv_title)
public TextView tvTitle;
@InjectView(R.id.rl_row)
public RelativeLayout rlRow;
public ViewHolder(View v) {
super(v);
ButterKnife.inject(this, v);
v.setOnClickListener(this);
}
@Override
public void onClick(View view) {
Log.e("item title",item.getTitle());
}
}
和onBindViewHolder设置你的视图持有人的项目:
public void onBindViewHolder(ViewHolder holder, int position) {
holder.tvTitle.setText(objects.get(position).getTitle());
holder.item = objects.get(position);
}
不幸的是,RecyclerView缺少ListView内置的几个功能。 例如,添加OnItemClickListener的能力,当一个项目被单击时触发。 RecyclerView允许你在适配器中设置一个OnClickListener,但是传递那个点击 从你的调用代码,到适配器,再到ViewHolder,监听器是复杂的 要捕捉一个简单的项目单击。
public class ItemClickSupport {
private final RecyclerView mRecyclerView;
private OnItemClickListener mOnItemClickListener;
private OnItemLongClickListener mOnItemLongClickListener;
private View.OnClickListener mOnClickListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mOnItemClickListener != null) {
RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
mOnItemClickListener.onItemClicked(mRecyclerView, holder.getAdapterPosition(), v);
}
}
};
private View.OnLongClickListener mOnLongClickListener = new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
if (mOnItemLongClickListener != null) {
RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
return mOnItemLongClickListener.onItemLongClicked(mRecyclerView, holder.getAdapterPosition(), v);
}
return false;
}
};
private RecyclerView.OnChildAttachStateChangeListener mAttachListener
= new RecyclerView.OnChildAttachStateChangeListener() {
@Override
public void onChildViewAttachedToWindow(View view) {
if (mOnItemClickListener != null) {
view.setOnClickListener(mOnClickListener);
}
if (mOnItemLongClickListener != null) {
view.setOnLongClickListener(mOnLongClickListener);
}
}
@Override
public void onChildViewDetachedFromWindow(View view) {
}
};
private ItemClickSupport(RecyclerView recyclerView) {
mRecyclerView = recyclerView;
mRecyclerView.setTag(R.id.item_click_support, this);
mRecyclerView.addOnChildAttachStateChangeListener(mAttachListener);
}
public static ItemClickSupport addTo(RecyclerView view) {
ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
if (support == null) {
support = new ItemClickSupport(view);
}
return support;
}
public static ItemClickSupport removeFrom(RecyclerView view) {
ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
if (support != null) {
support.detach(view);
}
return support;
}
public ItemClickSupport setOnItemClickListener(OnItemClickListener listener) {
mOnItemClickListener = listener;
return this;
}
public ItemClickSupport setOnItemLongClickListener(OnItemLongClickListener listener) {
mOnItemLongClickListener = listener;
return this;
}
private void detach(RecyclerView view) {
view.removeOnChildAttachStateChangeListener(mAttachListener);
view.setTag(R.id.item_click_support, null);
}
public interface OnItemClickListener {
void onItemClicked(RecyclerView recyclerView, int position, View v);
}
public interface OnItemLongClickListener {
boolean onItemLongClicked(RecyclerView recyclerView, int position, View v);
}
}
您还需要定义R.id。使用ids.xml:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<item name="item_click_support" type="id" />
</resources>
结果代码点击侦听器现在看起来像这样:
ItemClickSupport.addTo(mRecyclerView).setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
@Override
public void onItemClicked(RecyclerView recyclerView, int position, View v) {
// do it
}
});
关于recyclerview点击的简要说明,请看看这个littlerobots_blog
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