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

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;
    }
};

其他回答

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();
        }
    }

不幸的是,RecyclerView缺少ListView内置的几个功能。 例如,添加OnItemClickListener的能力,当一个项目被单击时触发。 RecyclerView允许你在适配器中设置一个OnClickListener,但是传递那个点击 从你的调用代码,到适配器,再到ViewHolder,监听器是复杂的 要捕捉一个简单的项目单击。

public class ItemClickSupport {
private final RecyclerView mRecyclerView;
private OnItemClickListener mOnItemClickListener;
private OnItemLongClickListener mOnItemLongClickListener;
private View.OnClickListener mOnClickListener = new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        if (mOnItemClickListener != null) {
            RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
            mOnItemClickListener.onItemClicked(mRecyclerView, holder.getAdapterPosition(), v);
        }
    }
};
private View.OnLongClickListener mOnLongClickListener = new View.OnLongClickListener() {
    @Override
    public boolean onLongClick(View v) {
        if (mOnItemLongClickListener != null) {
            RecyclerView.ViewHolder holder = mRecyclerView.getChildViewHolder(v);
            return mOnItemLongClickListener.onItemLongClicked(mRecyclerView, holder.getAdapterPosition(), v);
        }
        return false;
    }
};
private RecyclerView.OnChildAttachStateChangeListener mAttachListener
        = new RecyclerView.OnChildAttachStateChangeListener() {
    @Override
    public void onChildViewAttachedToWindow(View view) {
        if (mOnItemClickListener != null) {
            view.setOnClickListener(mOnClickListener);
        }
        if (mOnItemLongClickListener != null) {
            view.setOnLongClickListener(mOnLongClickListener);
        }
    }

    @Override
    public void onChildViewDetachedFromWindow(View view) {

    }
};

private ItemClickSupport(RecyclerView recyclerView) {
    mRecyclerView = recyclerView;
    mRecyclerView.setTag(R.id.item_click_support, this);
    mRecyclerView.addOnChildAttachStateChangeListener(mAttachListener);
}

public static ItemClickSupport addTo(RecyclerView view) {
    ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
    if (support == null) {
        support = new ItemClickSupport(view);
    }
    return support;
}

public static ItemClickSupport removeFrom(RecyclerView view) {
    ItemClickSupport support = (ItemClickSupport) view.getTag(R.id.item_click_support);
    if (support != null) {
        support.detach(view);
    }
    return support;
}

public ItemClickSupport setOnItemClickListener(OnItemClickListener listener) {
    mOnItemClickListener = listener;
    return this;
}

public ItemClickSupport setOnItemLongClickListener(OnItemLongClickListener listener) {
    mOnItemLongClickListener = listener;
    return this;
}

private void detach(RecyclerView view) {
    view.removeOnChildAttachStateChangeListener(mAttachListener);
    view.setTag(R.id.item_click_support, null);
}

public interface OnItemClickListener {

    void onItemClicked(RecyclerView recyclerView, int position, View v);
}

public interface OnItemLongClickListener {

    boolean onItemLongClicked(RecyclerView recyclerView, int position, View v);
}
}

您还需要定义R.id。使用ids.xml:

 <?xml version="1.0" encoding="utf-8"?>
 <resources>
  <item name="item_click_support" type="id" />
 </resources>

结果代码点击侦听器现在看起来像这样:

ItemClickSupport.addTo(mRecyclerView).setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
@Override
public void onItemClicked(RecyclerView recyclerView, int position, View v) {
    // do it
}
});

关于recyclerview点击的简要说明,请看看这个littlerobots_blog

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){}
}

查看类似的问题@CommonsWare的评论链接到this,它在viewHolder中实现了OnClickListener接口。

下面是ViewHolder的一个简单例子:

/** Declare global with in adapter class. */
TextView textView;

public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    private ViewHolder(View itemView) {
        super(itemView);
        itemView.setOnClickListener(this);
        textView = (TextView) view.findViewById(android.R.id.text1);   
    }

    @Override
    public void onClick(View view) {
        Toast.makeText(view.getContext(), "position = " + getLayoutPosition(), Toast.LENGTH_SHORT).show();
         
        /** Go through each item if you have few items within RecyclerView. */
        if (getLayoutPosition() == 0) {
           // Do whatever you want here
        } else if(getLayoutPosition() == 1) { 
           // Do whatever you want here
        } else if(getLayoutPosition() == 2) {
           // Do whatever you want here
        }

        /** Or you can use For loop if you have long list of items. */
        for (int i = 0; i < exampleList.size(); i++) {
            // Do whatever you want here
        }
    }
}

在你的RecyclerView中创建ViewHolder。适配器看起来像这样:

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    LayoutInflater inflater = LayoutInflater.from(parent.getContext())
    View view = inflater.inflate(android.R.layout.simple_list_item_1, parent, false);
    return new ViewHolder(view);
}

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;
}