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
基于Jacob Tabak的回答(+1),我能够添加onLongClick监听器:
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 {
public interface OnItemClickListener {
void onItemClick(View view, int position);
void onItemLongClick(View view, int position);
}
private OnItemClickListener mListener;
private 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 childView = recyclerView.findChildViewUnder(e.getX(), e.getY());
if (childView != null && mListener != null) {
mListener.onItemLongClick(childView, recyclerView.getChildAdapterPosition(childView));
}
}
});
}
@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 false;
}
@Override
public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) {
}
@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}
}
然后你可以这样使用它:
recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(getActivity(), recyclerView, new RecyclerItemClickListener.OnItemClickListener() {
@Override
public void onItemClick(View view, int position) {
// ...
}
@Override
public void onItemLongClick(View view, int position) {
// ...
}
}));
其他回答
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();
}
到目前为止,所有的答案都是很好的解决方案,但是如果你不想处理太多的实现细节,只是想让它类似于ListView的工作方式,我建议使用twway - view,如下所示:
https://github.com/lucasr/twoway-view
请注意,这个实现还支持长按项目,以及支持按下状态(这是这个问题的其他解决方案所缺乏的重要内容)。
如果您不想使用整个库,请查看ClickItemTouchListener类,如果需要,可以将其作为独立的类使用。我发现它目前唯一的问题是长按+滚动,它似乎有不正确的行为。
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
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();
}
}
让我们看看如何在Jetpack / AndroidX中实现这一点
你需要像这样在viewmodel类中创建一个观察对象
private MutableLiveData<Integer> adapterItem = new MutableLiveData<>();
public MutableLiveData<Integer> getAdapterItem() {
return adapterItem;
}
public void setAdapterItem(int adapterItem) {
this.getAdapterItem().setValue(adapterItem);
}
然后在适配器类中,确保将viewmodel引用作为构造函数的参数传递,然后在vieholder上实现clicklistener
public MyViewHolder(@NonNull View itemView) {
super(itemView);
if(itemView != null){
itemView.setOnClickListener(v -> {
int adapterPosition = getAdapterPosition();
viewModel.setAdapterItem(adapterPosition);
});
};
}
然后从活动课上观察变化
viewModel.getAdapterItem().observe(this, position -> {
Log.w(TAG, "clicked: " + ridesArray.get(position));
});
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