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

对于kotlin句柄,根据Jacobs的回答单击RecyclerView答案

创建类RecyclerItemClickListener:

class RecyclerItemClickListener(context: Context, recyclerView: RecyclerView, listner: OnItemClickListener) : RecyclerView.OnItemTouchListener {

    var mGestureDetector: GestureDetector
    var mListner: OnItemClickListener
    
    interface OnItemClickListener {
        fun onItemClick(view: View, position: Int)
        fun onLongItemClick(view: View, position: Int)
    }

    init {
        this.mListner = listner
        mGestureDetector = GestureDetector(context, object : GestureDetector.SimpleOnGestureListener() {
            override fun onSingleTapUp(e: MotionEvent?): Boolean = true
            
            override fun onLongPress(e: MotionEvent?) {
                val child: View? = recyclerView.findChildViewUnder(e!!.getX(), e.getY())
                if (child != null && mListner != null) {
                    mListner.onLongItemClick(child, recyclerView.getChildAdapterPosition(child))
                }
            }
        })
    }

    override fun onTouchEvent(rv: RecyclerView, e: MotionEvent) = Unit

    override fun onInterceptTouchEvent(view: RecyclerView, e: MotionEvent): Boolean {
        val childView: View? = view.findChildViewUnder(e!!.getX(), e.getY())
        if (childView != null && mListner != null && mGestureDetector.onTouchEvent(e)) {
            mListner.onItemClick(childView, view.getChildAdapterPosition(childView))
            return true
        }
        return false
    }

    override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) = Unit

}

点击Any RecyclerView(在活动/片段内):

recyclerView.addOnItemTouchListener(
    RecyclerItemClickListener(this, recyclerView, object : RecyclerItemClickListener.OnItemClickListener {
        override fun onItemClick(view: View, position: Int) {
            // TODO catch click
        }

        override fun onLongItemClick(view: View, position: Int) {
            // TODO catch click
        }
    })
)

其他回答

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;
    }
};

Recyclerview适配器与kotlin

在适配器中可以通过两种方式实现项目点击监听器。

第一种方法是使用界面

在你的活动课上:

class YourActivity : AppCompatActivity(), TestAdapter.ClickListener {
...
override fun itemClicked() {

}
...
}

在适配器类中:

class MyAdapter : RecyclerView.Adapter<MyAdapter.MyViewHolder> {
...
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
     holder.textView1.setOnClickListener { 
        clickListener.itemClicked(position) 
     }
}
...
interface ClickListener {
     fun itemClicked(position : Int)
}
...
}

第二种方法是使用callBack调用

在适配器类中:

class MyAdapter(val callBack: (pos:Int) -> Unit) : RecyclerView.Adapter<MyAdapter.MyViewHolder> {
...
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
     holder.textView1.setOnClickListener { 
        callBack(position)
     }
}
}

在你的活动课上:

class YourActivity : AppCompatActivity() {
...
val testAdapter = TestAdapter(
            callBack = { index ->
               
            })
binding.recyclerView.layoutManager = LinearLayoutManager(this)
binding.recyclerView.adapter = testAdapter
...
}

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();
}

我的方式

活动课上:

    public class MyActivity extends AppCompatActivity implements EmployeeAdapter.ClickListener {
    ...
    @Override
    public void onClick(int position) { ... }
    ...
    }

适配器类:

    public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
    ...
    @Override
    public void onBindViewHolder(){
         holder.textView1.setOnClickListener(v -> clickListener.onClick(position));
    }
    ...
    public interface ClickListener {
        void onClick(int position);
    }
    ...
    }

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();
        }
    }