【Android -- UI 开发】RecyclerView 实现列表点击事件(长按删除)

简介

RecyclerView 是 Android 中极其重要的一个高级 UI 控件，使用频率非常非常高，App 中 90% 以上的页面都会使用的到。由于其出色的性能和插拔式的架构设计，被全世界广大开发者一致称赞。

使用

1. 效果图

2. 布局文件

3. 适配器

public class HomeAdapter extends RecyclerView.Adapter {
    private List mList = new ArrayList();

    static class ViewHolder extends RecyclerView.ViewHolder {
        ImageView fruitImage;
        TextView fruitName;
        public ViewHolder(View itemView) {
            super(itemView);
            fruitImage = itemView.findViewById(R.id.iv_icon);
            fruitName = itemView.findViewById(R.id.tv_title);
        }
    }

    public void setData(List list) {
        this.mList.clear();
        this.mList.addAll(list);
        notifyDataSetChanged();
    }

    public void removeData(int position) {
        mList.remove(position);
        notifyItemRemoved(position);
        notifyDataSetChanged();
    }

    public void addData(int position) {
        mList.add(position,"ios");
        notifyItemInserted(position);
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int position) {
        return new ViewHolder(LayoutInflater.from(parent.getContext())
                .inflate(R.layout.item_recycler, parent, false));
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, final int position) {
        if (position % 2 == 0) {
            holder.itemView.setBackgroundColor(Color.parseColor("#191977d3"));
        } else {
            holder.itemView.setBackgroundColor(Color.parseColor("#fafafa"));
        }

        if (mOnItemClickListener != null) {
            holder.fruitImage.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    mOnItemClickListener.onClick(position);
                }
            });

            holder.fruitImage.setOnLongClickListener(new View.OnLongClickListener() {
                @Override
                public boolean onLongClick(View v) {
                    mOnItemClickListener.onLongClick(position);
                    return true;
                }
            });
        }


    }

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

    public interface OnItemClickListener {
        void onClick(int position);
        void onLongClick(int position);
    }

    private OnItemClickListener mOnItemClickListener;

    public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
        mOnItemClickListener = onItemClickListener;
    }

}

4. 分割线 用 mRecyclerView.addItemDecoration() 来加入分割线，谷歌没有提供默认的分割线需要我们继承 RecyclerView.ItemDecoration 来自定义分割线：

public class DividerItemDecoration extends RecyclerView.ItemDecoration {
    private static final int[] ATTRS = new int[]{
            android.R.attr.listDivider
    };
    public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
    public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
    private Drawable mDivider;
    private int mOrientation;
    public DividerItemDecoration(Context context, int orientation) {
        final TypedArray a = context.obtainStyledAttributes(ATTRS);
        mDivider = a.getDrawable(0);
        a.recycle();
        setOrientation(orientation);
    }
    public void setOrientation(int orientation) {
        if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
            throw new IllegalArgumentException("invalid orientation");
        }
        mOrientation = orientation;
    }
    @Override
    public void onDraw(Canvas c, RecyclerView parent) {
        if (mOrientation == VERTICAL_LIST) {
            drawVertical(c, parent);
        } else {
            drawHorizontal(c, parent);
        }

    }
    public void drawVertical(Canvas c, RecyclerView parent) {
        final int left = parent.getPaddingLeft();
        final int right = parent.getWidth() - parent.getPaddingRight();
        final int childCount = parent.getChildCount();
        for (int i = 0; i