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
nhaarman答案的Kotlin实现:
mRecyclerView.addOnItemTouchListener(object : RecyclerItemClickListener(this, mRecyclerView,object :RecyclerItemClickListener.OnItemClickListener{
override fun onItemClick(view: View, position: Int) {
}
override fun onLongItemClick(view: View?, position: Int) {
}
}){})
RecyclerItemClickListener.java:
import android.content.Context
import android.support.v7.widget.RecyclerView
import android.view.GestureDetector
import android.view.MotionEvent
import android.view.View
open class RecyclerItemClickListener(context: Context, recyclerView: RecyclerView, private val mListener: OnItemClickListener?) : RecyclerView.OnItemTouchListener {
private var mGestureDetector: GestureDetector
interface OnItemClickListener {
fun onItemClick(view: View, position: Int)
fun onLongItemClick(view: View?, position: Int)
}
init {
mGestureDetector = GestureDetector(context, object : GestureDetector.SimpleOnGestureListener() {
override fun onSingleTapUp(e: MotionEvent): Boolean {
return true
}
override fun onLongPress(e: MotionEvent) {
val child = recyclerView.findChildViewUnder(e.x, e.y)
if (child != null && mListener != null) {
mListener.onLongItemClick(child, recyclerView.getChildAdapterPosition(child))
}
}
})
}
override fun onInterceptTouchEvent(view: RecyclerView, e: MotionEvent): Boolean {
val childView = view.findChildViewUnder(e.x, e.y)
if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
mListener.onItemClick(childView, view.getChildAdapterPosition(childView))
return true
}
return false
}
override fun onTouchEvent(view: RecyclerView, motionEvent: MotionEvent) {}
override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) {}
}
其他回答
我知道有很多答案,但我想我也可以提供我的实现。(完整的细节可以在我回答的另一个问题中找到)。
所以,要添加一个点击监听器,你的内部ViewHolder类需要实现View.OnClickListener。这是因为你将设置一个OnClickListener到ViewHolder的构造函数的itemView参数。让我来告诉你我的意思:
public class ExampleClickViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
TextView text1, text2;
ExampleClickViewHolder(View itemView) {
super(itemView);
// we do this because we want to check when an item has been clicked:
itemView.setOnClickListener(this);
// now, like before, we assign our View variables
title = (TextView) itemView.findViewById(R.id.text1);
subtitle = (TextView) itemView.findViewById(R.id.text2);
}
@Override
public void onClick(View v) {
// The user may not set a click listener for list items, in which case our listener
// will be null, so we need to check for this
if (mOnEntryClickListener != null) {
mOnEntryClickListener.onEntryClick(v, getLayoutPosition());
}
}
}
唯一需要添加的其他东西是适配器的自定义接口和setter方法:
private OnEntryClickListener mOnEntryClickListener;
public interface OnEntryClickListener {
void onEntryClick(View view, int position);
}
public void setOnEntryClickListener(OnEntryClickListener onEntryClickListener) {
mOnEntryClickListener = onEntryClickListener;
}
这样,新的支持单击的适配器就完成了。
现在,让我们用它…
ExampleClickAdapter clickAdapter = new ExampleClickAdapter(yourObjects);
clickAdapter.setOnEntryClickListener(new ExampleClickAdapter.OnEntryClickListener() {
@Override
public void onEntryClick(View view, int position) {
// stuff that will happen when a list item is clicked
}
});
这基本上就是设置普通适配器的方法,除了使用您创建的setter方法来控制当用户单击特定列表项时要做什么。
你也可以看看我在GitHub上做的一组关于Gist的例子:
https://gist.github.com/FarbodSalamat-Zadeh/7646564f48ee708c1582c013e1de4f07
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();
}
});
}
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){}
}
您可以将clickListener传递给适配器。
在活动中:
private View.OnClickListener mItemClick = new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = null;
int position = list.getChildPosition(v);
switch (position) {
case 0:
intent = new Intent(MainActivity.this, LeakCanaryActivity.class);
break;
case 1:
intent = new Intent(MainActivity.this, ButterKnifeFragmentActivity.class);
break;
}
if (intent != null) {
MainActivity.this.startActivity(intent);
}
}
};
然后将它传递给适配器:
MainAdapter mainAdapter = new MainAdapter(this, mItemClick);
在适配器的onCreateViewHolder中:
@Override
public MainAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int position) {
View itemView = activity.getLayoutInflater().inflate(R.layout.main_adapter_item, viewGroup, false);
ViewHolder holder = new ViewHolder(itemView);
itemView.setOnClickListener(mItemClick);
return holder;
}
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