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
我已经看了所有的答案,并不是很满意。我找到了更简单快捷的方法。想分享给未来的读者。
选择单个回收项目中的任何视图。 获取这个View的父视图(确保你施放了合适的ViewGroup) 将onClickListener设置为这个父节点。
示例代码(它是在适配器的onBindViewHolder方法中编写的):
@Override
public void onBindViewHolder(@NonNull final ViewHolder holder, final int position) {
ConstraintLayout parent = (ConstraintLayout) holder.title.getParent();
parent.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(context, "Clicked recycler view item at position " + position, Toast.LENGTH_SHORT).show();
}
});
}
其他回答
这里有一个更好的和不那么紧密耦合的方式来实现一个OnClickListener的RecyclerView。
用法片段:
RecyclerView recyclerView = findViewById(R.id.recycler);
recyclerView.addOnItemTouchListener(
new RecyclerItemClickListener(context, recyclerView ,new RecyclerItemClickListener.OnItemClickListener() {
@Override public void onItemClick(View view, int position) {
// do whatever
}
@Override public void onLongItemClick(View view, int position) {
// do whatever
}
})
);
RecyclerItemClickListener实现:
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {
private OnItemClickListener mListener;
public interface OnItemClickListener {
public void onItemClick(View view, int position);
public void onLongItemClick(View view, int position);
}
GestureDetector mGestureDetector;
public RecyclerItemClickListener(Context context, final RecyclerView recyclerView, OnItemClickListener listener) {
mListener = listener;
mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onSingleTapUp(MotionEvent e) {
return true;
}
@Override
public void onLongPress(MotionEvent e) {
View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
if (child != null && mListener != null) {
mListener.onLongItemClick(child, recyclerView.getChildAdapterPosition(child));
}
}
});
}
@Override public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
View childView = view.findChildViewUnder(e.getX(), e.getY());
if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
mListener.onItemClick(childView, view.getChildAdapterPosition(childView));
return true;
}
return false;
}
@Override public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) { }
@Override
public void onRequestDisallowInterceptTouchEvent (boolean disallowIntercept){}
}
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
}
})
)
很简单,添加这个类:
public class OnItemClickListener implements View.OnClickListener {
private int position;
private OnItemClickCallback onItemClickCallback;
public OnItemClickListener(int position, OnItemClickCallback onItemClickCallback) {
this.position = position;
this.onItemClickCallback = onItemClickCallback;
}
@Override
public void onClick(View view) {
onItemClickCallback.onItemClicked(view, position);
}
public interface OnItemClickCallback {
void onItemClicked(View view, int position);
}
}
获取一个'OnItemClickCallback'接口实例,并把它放在你的activity或fragment中:
private OnItemClickListener.OnItemClickCallback onItemClickCallback = new OnItemClickListener.OnItemClickCallback() {
@Override
public void onItemClicked(View view, int position) {
}
};
然后,将这个回调传递给你的recyclerView:
recyclerView.setAdapter(new SimpleStringRecyclerViewAdapter(Arrays.asList("1", "2", "3"), onItemClickCallback));
最后,这将是你的适配器:
public class SimpleStringRecyclerViewAdapter extends RecyclerView.Adapter<SimpleStringRecyclerViewAdapter.ViewHolder> {
private List<String> mValues;
private OnItemClickListener.OnItemClickCallback onItemClickCallback;
public SimpleStringRecyclerViewAdapter(List<String> items, OnItemClickListener.OnItemClickCallback onItemClickCallback) {
mValues = items;
this.onItemClickCallback = onItemClickCallback;
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public final TextView mTextView;
public ViewHolder(View view) {
super(view);
mTextView = (TextView) view.findViewById(R.id.txt_title);
}
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item, parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.mTextView.setText(mValues.get(position));
holder.mTextView.setOnClickListener(new OnItemClickListener(position, onItemClickCallback));
}
@Override
public int getItemCount() {
return mValues.size();
}
}
步骤1)编写点击界面
创建一个名为RecyclerViewClickListener.java的接口,并添加以下代码。这里我们声明了两个方法onClick和onLongClick,分别用于标识项目单击和长单击。
package com.androidtutorialshub.recyclerviewtutorial.Helper;
import android.view.View;
public interface RecyclerViewClickListener {
void onClick(View view, int position);
void onLongClick(View view, int position);
}
步骤2)编写项目触摸类
创建一个名为RecyclerViewTouchListener.java的类,并添加以下代码。这里我们编写了检测点击和长按回收器视图项的逻辑。
package com.androidtutorialshub.recyclerviewtutorial.Helper;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
public class RecyclerViewTouchListener implements RecyclerView.OnItemTouchListener{
private GestureDetector gestureDetector;
private RecyclerViewClickListener clickListener;
public RecyclerViewTouchListener(Context context, final RecyclerView recyclerView, final RecyclerViewClickListener clickListener) {
this.clickListener = clickListener;
gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onSingleTapUp(MotionEvent e) {
return true;
}
@Override
public void onLongPress(MotionEvent e) {
View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
if (child != null && clickListener != null) {
clickListener.onLongClick(child, recyclerView.getChildPosition(child));
}
}
});
}
@Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
View child = rv.findChildViewUnder(e.getX(), e.getY());
if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
clickListener.onClick(child, rv.getChildPosition(child));
}
return false;
}
@Override
public void onTouchEvent(RecyclerView rv, MotionEvent e) {
}
@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}
}
步骤3)定义点击监听器
打开MainActivity.java并更新以下更改。这里onClick()方法将检测点击项目,onLongClick将检测长时间点击项目。
recyclerView.addOnItemTouchListener(new RecyclerViewTouchListener(getApplicationContext(), recyclerView, new RecyclerViewClickListener() {
@Override
public void onClick(View view, int position) {
Toast.makeText(getApplicationContext(), bookList.get(position).getTitle() + " is clicked!", Toast.LENGTH_SHORT).show();
}
@Override
public void onLongClick(View view, int position) {
Toast.makeText(getApplicationContext(), bookList.get(position).getTitle() + " is long pressed!", Toast.LENGTH_SHORT).show();
}
}));
欲了解更多信息或下载源代码:http://www.androidtutorialshub.com/android-recyclerview-click-listener-tutorial/
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。
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