RecycleView 实现瀑布流效果

1、用as开发，在build.gradle中添加依赖

dependencies {        ...        compile 'com.android.support:recyclerview-v7:21.0.3'    }

2、用Eclipse开发，添加jar包

3、在xml布局文件中添加一个recycleview的布局

<android.support.v7.widget.RecyclerView        android:id="@+id/card_recycler_view"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_marginLeft="7dp"        android:layout_marginTop="5dp"        android:scrollbars="vertical" />

4、activity的oncreate方法中添加如下关键代码

View view = inflater.inflate(R.layout.card_recycleview, null);card_recycler_view = (RecyclerView) view.findViewById(R.id.card_recycler_view);card_recycler_view.setHasFixedSize(false);StaggeredGridLayoutManager mStaggeredGridLayoutManager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);//表示两列，并且是竖直方向的瀑布流card_recycler_view.setLayoutManager(mStaggeredGridLayoutManager);

5、创建recycleview的数据适配器

public class RenQiAdapter2 extends RecyclerView.Adapter<RenQiAdapter2.ViewHolder> implements View.OnClickListener {    private List<StoreContent> data;//填充数据的集合    protected ImageLoader imageLoader = ImageLoader.getInstance();//采用universal imageloader来加载图片    public RenQiAdapter2(List<StoreContent> data) {        this.data = data;    }    public void setData(List<StoreContent> data) {        this.data = data;    }    @Override    public RenQiAdapter2.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {        View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.card_store_detail_item, viewGroup, false);        ViewHolder vh = new ViewHolder(view);        view.setOnClickListener(this);        return vh;    }    @Override    public void onBindViewHolder(final RenQiAdapter2.ViewHolder viewHolder, final int i) {        viewHolder.itemView.setTag(data.get(i));        viewHolder.iv_store.setImageResource(R.drawable.whitebottom);        viewHolder.iv_store.setTag(data.get(i).getCoverUrl());        imageLoader.loadImage(data.get(i).getCoverUrl(), BaseConstants.optionscopy, new ImageLoadingListener() {            @Override            public void onLoadingStarted(String s, View view) {            }            @Override            public void onLoadingFailed(String s, View view, FailReason failReason) {            }            @Override            public void onLoadingComplete(String imgUrl, View view, Bitmap bitmap) {                if (viewHolder.iv_store.getTag() != null                        && viewHolder.iv_store.getTag().equals(imgUrl)) {                    //此处代码获取屏幕的宽高，实现不同屏幕的适配                    int width = BaseApplication.getWindowWidth() / 2;                    int height = width * bitmap.getHeight() / bitmap.getWidth();//高通过宽等比例缩放                    RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(                            width, height);                    viewHolder.iv_store.setLayoutParams(params);                    viewHolder.iv_store.setImageBitmap(bitmap);                    viewHolder.tv_date.setText("总销"                            + data.get(i).getSale() + "件");                    viewHolder.tv_price.setText("¥ "                            + CommonUtils.getShortPrice(                            data.get(i).getSalePrice(),                            2));                }            }            @Override            public void onLoadingCancelled(String s, View view) {            }        });    }    @Override    public int getItemCount() {        return data.size();    }    @Override    public void onClick(View v) {        if (null != mOnItemClickListener) {            mOnItemClickListener.onClick(v, (StoreContent) v.getTag());        }    }    //创建一个viewholder类    public static class ViewHolder extends RecyclerView.ViewHolder {        ImageView iv_store;        TextView tv_date;        TextView tv_price;        public ViewHolder(View itemView) {            super(itemView);            iv_store = (ImageView) itemView.findViewById(R.id.iv_store);            tv_date = (TextView) itemView.findViewById(R.id.tv_date);            tv_price = (TextView) itemView.findViewById(R.id.tv_price);        }    }    private OnRecyclerViewItemClickListener mOnItemClickListener = null;    public void setOnItemClickListener(OnRecyclerViewItemClickListener listener) {        this.mOnItemClickListener = listener;    }    public static interface OnRecyclerViewItemClickListener {        void onClick(View view, StoreContent itemData);    }}

注：recycleview的数据适配器，继承RecycleView.Adapter的子类，此处继承的是我在本类中定义的ViewHolder。强制重写的方法：

onCreateViewHolder(),onBindViewHolder(),和getItemCount();

在onCreateViewHolder(),方法中，需要返回，与当前adapter绑定的viewholder；

在onBindViewHolder()方法中，将数据填充到控件中；

getItemCont()的作用与listview的adapter方法中的getItemCount()一样。

6、给RecycleView添加adapter

if (null == rebateAdapter) {            rebateAdapter = new RebateAdapter(activity, value);            card_staggeredgridview.setAdapter(rebateAdapter);            card_staggeredgridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {                @Override                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {                    RebateDetail item = (RebateDetail) card_staggeredgridview.getAdapter().getItem(position);                    ...                }            });        } else {            rebateAdapter.setData(value);            rebateAdapter.notifyDataSetChanged();        }

7、RecycleView仿造listview的onItemClick方法

7.1在adapter中定义一个接口，和抽象方法；

public static interface OnRecyclerViewItemClickListener {        void onClick(View view, StoreContent itemData);    }

7.2在adapter中定义一接口对象，并添加set方法；

 private OnRecyclerViewItemClickListener mOnItemClickListener = null;    public void setOnItemClickListener(OnRecyclerViewItemClickListener listener) {        this.mOnItemClickListener = listener;    }

7.3adapter类实现View的onClickListener接口，重写抽象方法

public class RenQiAdapter2 extends RecyclerView.Adapter<RenQiAdapter2.ViewHolder> implements View.OnClickListener {.......@Override    public void onClick(View v) {        if (null != mOnItemClickListener) {            mOnItemClickListener.onClick(v, (StoreContent) v.getTag());        }    }}

7.4 在bindviewholder方法中，将数据传递给view

 @Override    public void onBindViewHolder(final RenQiAdapter2.ViewHolder viewHolder, final int i) {    ......    viewHolder.itemView.setTag(data.get(i));    ......}

7.5 给recycleview添加onitemclick方法

 card_staggeredgridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {                @Override                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {                    RebateDetail item = (RebateDetail) card_staggeredgridview.getAdapter().getItem(position);                    Intent intent = new Intent(activity, BaoBeiDetailActivity.class);                    intent.putExtra("itemid", item.getItemId());                    intent.putExtra("clickPostion", position);                    activity.startActivity(intent);                    activity.overridePendingTransition(R.anim.tran_in, R.anim.tran_out);                }            });

8、RecycleView 的数据更新

listview中更新数据，通过的方法是notifyDataSetChanged()

RecycleView中，可以只更新一条数据

在adapter类中，定义如下方法；可以在其他地方调用

public void changeData(int position){        notifyItemChanged(position);    }    public void addData(int position){        notifyItemInserted(position);    }    public void removeData(int position){        notifyItemRemoved(position);    }