Android. Java. RecyclerAdapter

Question

我在一个布局中拥有两种不同的卡片视图。我希望将最新的新闻添加到其中一个卡片视图中，其余新闻添加到另一个中。例如，如下图所示：

以下是我的 MyRecyclerAdapter 代码：

public class MyRecyclerAdapter extends RecyclerView.Adapter<MyRecyclerAdapter.CustomViewHolder> {
    private List<FeedItem> feedItemList;
    private Context mContext;

    public MyRecyclerAdapter(Context context, List<FeedItem> feedItemList) {
        this.feedItemList = feedItemList;
        this.mContext = context;
    }

    @Override
    public CustomViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.list_row, null);
        CustomViewHolder viewHolder = new CustomViewHolder(view);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(CustomViewHolder customViewHolder, int i) {
        FeedItem feedItem = feedItemList.get(i);

        //Download image using picasso library
        Picasso.with(mContext).load(feedItem.getThumbnail())
                .error(R.drawable.placeholder)
                .placeholder(R.drawable.placeholder)
                .into(customViewHolder.imageView);

        //Setting text view title
        customViewHolder.textView.setText(Html.fromHtml(feedItem.getTitle()));

        View.OnClickListener clickListener = new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                CustomViewHolder holder = (CustomViewHolder) view.getTag();
                int position = holder.getPosition();

                FeedItem feedItem = feedItemList.get(position);
                Toast.makeText(mContext, feedItem.getTitle(), Toast.LENGTH_SHORT).show();
            }
        };

        //Handle click event on both title and image click
        customViewHolder.textView.setOnClickListener(clickListener);
        customViewHolder.imageView.setOnClickListener(clickListener);

        customViewHolder.textView.setTag(customViewHolder);
        customViewHolder.imageView.setTag(customViewHolder);
    }

    @Override
    public int getItemCount() {
        return (null != feedItemList ? feedItemList.size() : 0);
    }

    public class CustomViewHolder extends RecyclerView.ViewHolder {
        protected ImageView imageView;
        protected TextView textView;

        public CustomViewHolder(View view) {
            super(view);
            this.imageView = (ImageView) view.findViewById(R.id.thumbnail);
            this.textView = (TextView) view.findViewById(R.id.title);
        }
    }
}

- user6075877

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什么是问题？你是否遇到了错误？有什么东西不能正常工作吗？ - Timothée Bourguignon

Answer 1

如果我是你，想要完成你在图片中发布的内容，我会采用以下方法：覆盖getItemViewType并拥有两种不同类型的ViewHolder，一种用于header，即具有大图像的ViewHolder，另一种适配器用于小行。 onBindViewHolder将类型作为参数传递。在你的情况下是int i。

- Blackbelt

---

你可以用代码来写吗？但是我不懂……请 - user6075877

Answer 2

我写了一个快速演示，代码如下：

private class MyCustomAdapter extends BaseAdapter {

        private static final int TYPE_ITEM = 0;
        private static final int TYPE_SEPARATOR = 1;
        private static final int TYPE_MAX_COUNT = TYPE_SEPARATOR + 1;

        private ArrayList mData = new ArrayList();
        private LayoutInflater mInflater;

        private TreeSet mSeparatorSet = new TreeSet();

        public MyCustomAdapter() {
            mInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        }

        public void addItem(String item) {
            mData.add(item);
            notifyDataSetChanged();
        }

        public void addSeparator(String item) {
            mData.add(item);
            mSeparatorSet.add(mData.size() - 1);
            notifyDataSetChanged();
        }

        @Override
        public int getItemViewType(int position) {
            return mSeparatorSet.contains(position) ? TYPE_SEPARATOR : TYPE_ITEM;

        }

        @Override
        public int getViewTypeCount() {
            return TYPE_MAX_COUNT;
        }

        @Override
        public int getCount() {
            return mData.size();
        }

        @Override
        public Object getItem(int position) {
            return mData.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            int type = getItemViewType(position);
            System.out.println("getView " + position + " " + convertView + "type " + type);
            ViewHolder holder = null;
            if (convertView == null) {
                holder = new ViewHolder();
                switch (type) {
                    case TYPE_ITEM:
                        convertView = mInflater.inflate(R.layout.item1, null);
                        holder.textView = (TextView) convertView.findViewById(R.id.text_view);
                        break;
                    case TYPE_SEPARATOR:
                        convertView = mInflater.inflate(R.layout.item2, null);
                        holder.textView = (TextView) convertView.findViewById(R.id.textSeparator);
                        break;
                }
                convertView.setTag(holder);
            } else {
                holder = (ViewHolder) convertView.getTag();
            }
            holder.textView.setText(mData.get(position) + "");
            return convertView;
        }
    }

    public static class ViewHolder {
        public TextView textView;
    }

或者如果你想使用页眉和页脚，可以创建headerView布局：

View header = (View) getLayoutInflater().inflate(R.layout.headerView,null);
listView.addHeaderView(header);

- Truong Vu