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

在ViewHolder中设置点击监听器,如下所示:

public class MyViewHolder extends RecyclerView.ViewHolder {
    public TextView title, year, genre;

    public MyViewHolder(View view) {
        super(view);

        title = (TextView) view.findViewById(R.id.title);
        genre = (TextView) view.findViewById(R.id.genre);
        year = (TextView) view.findViewById(R.id.year);

        view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(context, ""+getAdapterPosition(), Toast.LENGTH_SHORT).show();
            }
        });
    }
}

其他回答

如果你想在个别项目上捕捉点击事件,那么只需在ViewHolder类中实现OnClickListener,然后在个别视图或整个itemView上设置点击侦听器。

下面的例子说明了同样的情况

public  class ContactViewHolder extends RecyclerView.ViewHolder implements OnClickListener
    {
        TextView txt_title,txt_name,txt_email;

        public ContactViewHolder(View itemView) 
        {
            super(itemView);
            txt_title = (TextView)itemView.findViewById(R.id.txt_title);
            txt_name  = (TextView)itemView.findViewById(R.id.txt_name);
            txt_email = (TextView)itemView.findViewById(R.id.txt_email);

            txt_name.setOnClickListener(this);
            txt_email.setOnClickListener(this);
            itemView.setOnClickListener(this);
        }

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

            if(v == itemView)
            {
                Toast.makeText(RecyclerDemoActivity.this, "Visiting Card Clicked is ==>"+txt_name.getText(), Toast.LENGTH_SHORT).show();
            }

            if(v == txt_name)
            {
                Toast.makeText(RecyclerDemoActivity.this, "Name ==>"+txt_name.getText(), Toast.LENGTH_SHORT).show();
            }

            if(v == txt_email)
            {
                Toast.makeText(RecyclerDemoActivity.this, "Email ==>"+txt_email.getText(), Toast.LENGTH_SHORT).show();
            }
        }

    }
} 

这是我的自定义适配器的完整代码,这段代码将用XML文件“list_item”中定义的列表项膨胀行,它还将在具有各自位置的所有列表项行上执行单击事件。

public class MyCustomAdapter extends RecyclerView.Adapter`<`AdapterMyCustomAdapter.ViewHolder> {

    public static class ViewHolder extends RecyclerView.ViewHolder implements OnClickListener {
        public onItemClickListener mListener;
        public ViewHolder(View v, onItemClickListener listener) {
            super(v);
            mListener =listener;
            v.setOnClickListener(this);
        }

        @Override
        public void onClick(View v) {
            mListener.onRecyclerItemClick(v, getPosition());
        }

        public static interface onItemClickListener {
            public void onRecyclerItemClick(View view , int position);
        }
    }

    @Override
    public int getItemCount() {
        return 5;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int pos) {      

    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int position) {
        View v = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_item, parent, false);

    /* here list_item is an xml file we want to inflate ...it is same as we do in case of listview for customization.*/

        MyCustomAdapter.ViewHolder vh = new ViewHolder(v, new MyCustomAdapter.ViewHolder.onItemClickListener() {

            @Override
            public void onRecyclerItemClick(View view, int position) {
                System.out.println("clicked on list item at position " +position);
            } 
        });
        return vh;
    }
}

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。

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) {
        // ...
    }
}));

我们可以使用Java弱引用来实现这一点。 从语义上讲,视图持有者应该响应click事件或将其委托给正确的响应器。

我们的目标:

Viewholder应该对响应事件的类一无所知,除非它实现了某个接口。 点击处理程序应该得到被点击的视图在RecyclerView中的位置。 我们应该能够辨别视图持有人中单击了哪个视图。 保持所有组件之间的松散耦合,不要造成任何保留周期。

步骤:

Create an interface to handle click responses. Implement this interface in the Activity that will handle the click. Add a member variable in the RecyclerView Adapter to hold the Weak Reference and a constructor that sets it. Do the same in the RecyclerView ViewHolder and add a member variable to keep track of position. Set your on click listeners on any view you'd like in the ViewHolder, then callback to the responder to handle them. Change your onBindViewHolder method to set the position when binding. Pass the responder down to the ViewHolder. In the responder, you can now use getId() on the view to figure out which view was clicked.

这里是一个要点,这样你就可以看到它们是如何组合在一起的: RecyclerView点击处理