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

这就是重用View的方法。OnClickListener:

public class TestAdapter extends RecyclerView.Adapter<TestAdapter.MyviewHolder>
    implements View.OnClickListener

在ViewHoder中获取项目布局的父视图:

public class MyviewHolder extends RecyclerView.ViewHolder {

    LinearLayout linearLayout;

    public MyviewHolder(View itemView) {
        super(itemView);
        linearLayout = itemView.findViewById(R.id.linear_layout_item);
    }
}

在onBindViewHolder中设置标签为位置:

@Override
public void onBindViewHolder(MyviewHolder holder, int position) {
    holder.linearLayout.setTag(position);
    holder.linearLayout.setOnClickListener(this);
}

在你的onClick实现中:

@Override
public void onClick(View v) {
    int position = (int) v.getTag();

    switch (v.getId()) {
        case R.id.linear_layout_item:
            // do some thing with position 
            break;
    }
}

其他回答

我是这样做的,没有不必要的类、检测器等。适配器中的简单代码。特别是针对longClick的更好解决方案。

public class PasswordAdapter extends RecyclerView.Adapter<PasswordAdapter.ViewHolder> {
    private final ClickListener clickListener;

    public PasswordAdapter(ClickListener clickListener) {
         this.clickListener = clickListener;
    }

    public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener, View.OnLongClickListener {
        TextView name;

        public ViewHolder(View itemView) {
            super(itemView);
            itemView.setOnClickListener(this);
            itemView.setOnLongClickListener(this);
            name = (TextView) itemView.findViewById(R.id.card_name);
        }

        @Override
        public void onClick(View v) {
            int position = getBindingAdapterPosition();
            if (position >= 0) {
                clickListener.onItemClick(position, v);
            }
        }

        @Override
        public boolean onLongClick(View v) {
            int position = getBindingAdapterPosition();
            if (position >= 0) { 
                clickListener.onItemLongClick(position, v);
                return true;
            }
            return false;
        }
    }

    public interface ClickListener {
        void onItemClick(int position, View v);
        void onItemLongClick(int position, View v);
    }
}

然后在片段或活动中,点击:

PasswordAdapter mAdapter = new PasswordAdapter(
    new PasswordAdapter.ClickListener() {
        @Override
        public void onItemClick(int position, View v) {
            Log.d(TAG, "onItemClick position: " + position);
        }

        @Override
        public void onItemLongClick(int position, View v) {
            Log.d(TAG, "onItemLongClick pos = " + position);
        }
    }
);

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;
    }
};

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();
}

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);
}

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