javascript - RecyclerView解析JSON数据后添加onClick

Question

我有一个 fragment ，其中有一个 RecyclerView。我从网页解析了 JSON 数据，并使用教程将其显示在这个 RecyclerView 中:https://www.learn2crack.com/2016/02/recyclerview-json-parsing.html

现在我想为 RecyclerView 项目添加一个 onClick。我知道如何对静态 RecyclerView 项目执行此操作，但在这种情况下不知道如何设置 setOnClickListener。对于静态 recyclerview 项目，我将此类用于 onClick 事件。

package com.parassidhu.cdlumaths;

import android.support.v7.widget.RecyclerView;
import android.view.View;

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);
    }
}

我的适配器类是:

package com.parassidhu.cdlumaths;

import android.content.ClipData;
import android.content.Intent;
import android.net.Uri;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;

import com.parassidhu.cdlumaths.R;
import com.parassidhu.cdlumaths.Android;

import java.util.ArrayList;

public class NoticesData extends RecyclerView.Adapter<NoticesData.ViewHolder> {

    private ArrayList<Android> mAndroidList;
    private RecyclerView recyclerView;
    public NoticesData(ArrayList<Android> androidList, RecyclerView rcl) {
        mAndroidList = androidList;
        recyclerView=rcl;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.notices_row, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, int position) {
        holder.mTvName.setText(mAndroidList.get(position).getName());
        ItemClickSupport.addTo(recyclerView).setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
            @Override
            public void onItemClicked(RecyclerView recyclerView, int position, View v) {
            //I can't call Toast or startIntent here
            }
        });
    }

    @Override
    public int getItemCount() {
        return mAndroidList.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder{

        private TextView mTvName;
        public ViewHolder(View view) {
            super(view);
            mTvName = (TextView)view.findViewById(R.id.tv_name);
        }
    }
}

Answer 1

在您的 Activity 或 Fragment 类中创建如下所示的方法

public void showToast(int position) {
  Toast.makeText(getActivity(), "Clicked position is " + position, Toast.LENGTH_SHORT).show();
}

(我认为您使用的是 Fragment，所以我使用了 getActivity())

现在像这样更新您的 Adapter 构造函数

...
...
private YourFragment frag;

public NoticesData(ArrayList<Android> androidList, RecyclerView rcl, YourFragment fragment) {
    mAndroidList = androidList;
    recyclerView = rcl;
    frag = fragment;
}

在你的 Fragment 中像这样更新 Adapter 初始化

NoticesData notice = NoticesData(androidList, rcl, YourFragment.this);

现在在 Adapter 中调用 showToast() 方法

ItemClickSupport.addTo(recyclerView).setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
        @Override
        public void onItemClicked(RecyclerView recyclerView, int position, View v) {

           frag.showToast(position);  // it's like callback method

        }
    });

注意:这里的 YourFragment 表示托管 RecyclerView 的 Fragment。