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
对于kotlin句柄,根据Jacobs的回答单击RecyclerView答案
创建类RecyclerItemClickListener:
class RecyclerItemClickListener(context: Context, recyclerView: RecyclerView, listner: OnItemClickListener) : RecyclerView.OnItemTouchListener {
var mGestureDetector: GestureDetector
var mListner: OnItemClickListener
interface OnItemClickListener {
fun onItemClick(view: View, position: Int)
fun onLongItemClick(view: View, position: Int)
}
init {
this.mListner = listner
mGestureDetector = GestureDetector(context, object : GestureDetector.SimpleOnGestureListener() {
override fun onSingleTapUp(e: MotionEvent?): Boolean = true
override fun onLongPress(e: MotionEvent?) {
val child: View? = recyclerView.findChildViewUnder(e!!.getX(), e.getY())
if (child != null && mListner != null) {
mListner.onLongItemClick(child, recyclerView.getChildAdapterPosition(child))
}
}
})
}
override fun onTouchEvent(rv: RecyclerView, e: MotionEvent) = Unit
override fun onInterceptTouchEvent(view: RecyclerView, e: MotionEvent): Boolean {
val childView: View? = view.findChildViewUnder(e!!.getX(), e.getY())
if (childView != null && mListner != null && mGestureDetector.onTouchEvent(e)) {
mListner.onItemClick(childView, view.getChildAdapterPosition(childView))
return true
}
return false
}
override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) = Unit
}
点击Any RecyclerView(在活动/片段内):
recyclerView.addOnItemTouchListener(
RecyclerItemClickListener(this, recyclerView, object : RecyclerItemClickListener.OnItemClickListener {
override fun onItemClick(view: View, position: Int) {
// TODO catch click
}
override fun onLongItemClick(view: View, position: Int) {
// TODO catch click
}
})
)
其他回答
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;
}
};
Recyclerview适配器与kotlin
在适配器中可以通过两种方式实现项目点击监听器。
第一种方法是使用界面
在你的活动课上:
class YourActivity : AppCompatActivity(), TestAdapter.ClickListener {
...
override fun itemClicked() {
}
...
}
在适配器类中:
class MyAdapter : RecyclerView.Adapter<MyAdapter.MyViewHolder> {
...
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.textView1.setOnClickListener {
clickListener.itemClicked(position)
}
}
...
interface ClickListener {
fun itemClicked(position : Int)
}
...
}
第二种方法是使用callBack调用
在适配器类中:
class MyAdapter(val callBack: (pos:Int) -> Unit) : RecyclerView.Adapter<MyAdapter.MyViewHolder> {
...
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.textView1.setOnClickListener {
callBack(position)
}
}
}
在你的活动课上:
class YourActivity : AppCompatActivity() {
...
val testAdapter = TestAdapter(
callBack = { index ->
})
binding.recyclerView.layoutManager = LinearLayoutManager(this)
binding.recyclerView.adapter = testAdapter
...
}
由于API已经发生了根本性的变化,如果你要为每个项目创建一个OnClickListener,这不会让我感到惊讶。不过也没那么麻烦。在你的RecyclerView的实现中。适配器<MyViewHolder>,你应该有:
private final OnClickListener mOnClickListener = new MyOnClickListener();
@Override
public MyViewHolder onCreateViewHolder(final ViewGroup parent, final int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.myview, parent, false);
view.setOnClickListener(mOnClickListener);
return new MyViewHolder(view);
}
onClick方法:
@Override
public void onClick(final View view) {
int itemPosition = mRecyclerView.getChildLayoutPosition(view);
String item = mList.get(itemPosition);
Toast.makeText(mContext, item, Toast.LENGTH_LONG).show();
}
我的方式
活动课上:
public class MyActivity extends AppCompatActivity implements EmployeeAdapter.ClickListener {
...
@Override
public void onClick(int position) { ... }
...
}
适配器类:
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
...
@Override
public void onBindViewHolder(){
holder.textView1.setOnClickListener(v -> clickListener.onClick(position));
}
...
public interface ClickListener {
void onClick(int position);
}
...
}
太简单和有效了。
而不是实现接口视图。OnClickListener内的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();
}
}
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