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使用起来超级方便的RecyclerView,支持头尾,滚动到尾部

2017-03-27  本文已影响409人  丶dtdsn
这是一个继承自recyclerView,并且修改的recyclerView
支持头尾添加,滚动到尾部监听,方法链式调用。在瀑布流,Gird的形态下,头尾依然单独占用一行,已经做了修正
将这个自定义recyclerview的java文件放到你的项目里,就可以开始用了
图片

如何使用

1.文章的最下方拷贝recycleView的代码到你的项目里。

2.在布局里引用

<你的包名.PerfectRecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></你的包名.PerfectRecyclerView>

3.代码中使用

1.
PerfectRecyclerView  mRecyclerView = (PerfectRecyclerView) findViewById(R.id.recyclerView);

2.

  //一个正常RecyclerView  adapter  下方有这个adapter代码
  RvAdapter rvAdapter = new RvAdapter();

  //初始化,然后全程链式调用,注意调用顺序
  //1.设置容器 2.设置adapter 
  // 头尾随意使用
  mRecyclerView.
                /**
                 *  设置容器
                 *  竖的list
                 *  setLayoutManagerVerticalLinear()
                 *  横的list
                 *  .setLayoutManagerHorizontalLinear()
                 *  竖的Grid
                 *  setLayoutManagerVerticalGird(int行数)
                 *  横的Grid
                 *  setLayoutManagerHorizontalGird(int行数)
                 *  竖 瀑布流
                 *  setLayoutManagerVerticalStaggered(int行数)
                 *  横 瀑布流
                 *  setLayoutManagerHorizontalStaggered(int行数)
                 */
             
                //设置adapter
                .setAdapterPerfect(rvAdapter)

/**
*注意:如果添加了头布局,
*那么ViewHolder内的getPosition()方法返回的是position+1,正确需要getPosition()-1
*getAdapterPosition() 将返回你的adapter内的 position,所以假如调用刷新,需要 *getAdapterPosition()+1
*/
                 //添加头布局
                .addHeaderView(R.layout.header_view)

                //添加脚布局
                .addFooterView(R.layout.footer_view)

                //滚动到脚布局监听
                .addScrollBottom(new PerfectRecyclerView.OnScrollBottom() {
                        @Override
                        public void scrollBottom() {
                               //滑动到底部监听
                              //这里注意:对list进行判断
                               if (list != null && list.size() > 0) {
                                  //加载数据,然后刷新
                                (注意:原notifyDataSetChanged()等一系列刷新方法已经改变,下  
                                 方有说明)
                              }
                        }
                });

  ////////////////////////////////////////////////////////////////////////////////////////              
          /**
           *完整示例
          */
        mRecyclerView.setLayoutManagerVerticalLinear()
                .setAdapterPerfect(adapter)
                .addHeaderView(R.layout.header)
                .addFooterView(R.layout.foot)
                .addScrollBottom(new PerfectRecyclerView.OnScrollBottom() {
                    @Override
                    public void scrollBottom() {

                    }
                });

  ////////////////////////////////////////////////////////////////////////////////////////       
        
        /**
         *   一些返回方法
         */

        //返回容器
        RecyclerView.LayoutManager layoutManager = mRecyclerView.getLayoutManager();
        
        //返回头布局view
        View header = mRecyclerView.getHeaderParent();

            //使用这个header进行findViewById你的布局内的子view
            //举例
            TextView tv = header.findViewById(R.id.tv1);
        
        //返回为脚布局view  同头布局一样
        View footer = mRecyclerView.getFooterParent();
        

正常的RecyclerView Apapter

//和正常的adapter一样
    class RvAdapter extends RecyclerView.Adapter<RvAdapter.RvHolder > {

        @Override
        public RvHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            return new RvHolder (LayoutInflater.from(parent.getContext()).inflate(R.layout.dialog_gallery, parent, false));
        }

        @Override
        public void onBindViewHolder(RvHolder  holder, int position) {
             //无论你添加了头尾,这里的position都是的正确的position
            holder.tv.setText(list.get(position));
        }

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

        class RvHolder extends RecyclerView.ViewHolder {
            private TextView tv;
            public RvHolder (View itemView) {
                super(itemView);
                tv = itemView.findViewById(R.id.tv1);
            }
        }
    }

提供一个稍微简易的adapter,将它复制到你的项目里

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import java.util.List;


public abstract class PerfectAdapter<T extends RecyclerView.ViewHolder, E> extends RecyclerView.Adapter<T> {
    private int layout;
    private List<E> list;

    
    
    public PerfectAdapter(List<E> list, int layout) {
        this.list = list;
        this.layout = layout;
    }

    @Override
    public T onCreateViewHolder(ViewGroup viewGroup, int i) {
        View view = LayoutInflater.from(viewGroup.getContext()).inflate(layout, viewGroup, false);
        return getHolder(view);
    }

    protected abstract T getHolder(View view);

    @Override
    public void onBindViewHolder(T t, int position) {
        E bean = list.get(position);
        bindView(t, position, bean);
    }

    protected abstract void bindView(T t, int position, E bean);

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

如何使用这个简易adapter

//1.先写一个viewholder
     class RvHolder extends RecyclerView.ViewHolder {
            private TextView tv;
            public RvHolder (View itemView) {
                super(itemView);
                tv = itemView.findViewById(R.id.tv1);
            }
        }

//2.使用这个简易的adapter
    BaseRvAdapter  rvAdapter = new BaseRvAdapter<RvHolder, JavaBean>(list,R.layout.item) {
            @Override
            protected RvHolder getHolder(View view) {
                return new RvHolder(view);
            }

            @Override
            protected void bindView(RvHolder rvHolder, int position, JavaBean bean) {
                     //无论你添加了头尾,这里的position都是的正确的position
                      rvHolder.tv.setText(bean);
            }
        };

注意

刷新方法不再是你的 adapter.notifyDataSetChanged()
调用这个方法将不会再刷新你的RecyclerView

正确的刷新方法请使用
      //全局刷新
        mRecyclerView.notifyDataSetChanged();
      //某条目刷新
        mRecyclerView.notifyItemChanged(int);
      //插入某条目
        mRecyclerView.notifyItemInserted(int);
      //删除某条目
        mRecyclerView.notifyItemRemoved(int);

ViewHolder内的getPosition()与getAdapterPosition() 方法使用注意
如果你添加了头布局,
当你需要刷新某一条时候
那么正确的 getPosition() = getPosition()-1
正确的getAdapterPosition() = getAdapterPosition()+1

这里是这个RecyclerView的源码,复制到你的项目里就可以使用了

import android.content.Context;
import android.support.annotation.LayoutRes;
import android.support.annotation.Nullable;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


public class PerfectRecyclerView extends RecyclerView {
    private View mHeaderView;
    private View mFooterView;
    private PerfectAdapter perfectAdapter;
    private Context context;
    private boolean loadMoreSwitch = true;



    public PerfectRecyclerView(Context context) {
        super(context);
    }

    public PerfectRecyclerView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public PerfectRecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        this.context = context;
    }

    public PerfectRecyclerView addHeaderView(@LayoutRes int id) {
        mHeaderView = LayoutInflater.from(getContext()).inflate(id, this, false);
        perfectAdapter.notifyItemInserted(0);
        return this;
    }

    public PerfectRecyclerView addFooterView(@LayoutRes int id) {
        mFooterView = LayoutInflater.from(getContext()).inflate(id, this, false);
        perfectAdapter.notifyItemInserted(perfectAdapter.getItemCount() - 1);
        return this;
    }

    public void closeLoadMore() {
        loadMoreSwitch = false;
    }

    public View getFooterParent() {
        return mFooterView;
    }

    public View getHeaderParent() {
        return mHeaderView;
    }

    public void notifyItemInserted(int i) {
        if (mHeaderView != null) i++;
        perfectAdapter.notifyItemInserted(i);
    }

    public void notifyItemChanged(int i) {
        if (mHeaderView != null) i++;
        perfectAdapter.notifyItemChanged(i);
    }

    public void notifyItemRemoved(int i) {
        if (mHeaderView != null) i++;
        perfectAdapter.notifyItemRemoved(i);
    }


    public void notifyDataSetChanged() {
        perfectAdapter.notifyDataSetChanged();
    }


    @Deprecated
    @Override
    public void setAdapter(Adapter adapter) {
        if (adapter != null) {
            perfectAdapter = new PerfectAdapter(adapter);
        }
        super.setAdapter(perfectAdapter);
    }

    public PerfectRecyclerView setAdapterPerfect(Adapter adapter) {
        this.setAdapter(adapter);
        return this;
    }

    @Override
    public void onScrolled(int dx, int dy) {
        super.onScrolled(dx, dy);
        if (onRollingRequestMore != null) {
            if (isSlideToBottom() && loadMoreSwitch) {
                onRollingRequestMore.scrollBottom();
            }
        }
    }

    @Override
    public void onNestedPreScroll(View target, int dx, int dy, int[] consumed) {
        if (((RecyclerView) target).getChildAt(0).getY() == 0) {
            scollTop.isScollTop();
        }

        super.onNestedPreScroll(target, dx, dy, consumed);

    }


    private ScollTop scollTop;

    public PerfectRecyclerView scollTop(ScollTop scollTop) {
        this.scollTop = scollTop;
        return this;
    }

    public interface ScollTop {
        void isScollTop();
    }



    //VerticalLinear
    public PerfectRecyclerView setLayoutManagerVerticalLinear() {
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(context);
        layoutManager = linearLayoutManager;
        linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        this.setLayoutManager(linearLayoutManager);
        return this;
    }

    //HorizontalLinear
    public PerfectRecyclerView setLayoutManagerHorizontalLinear() {
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(context);
        layoutManager = linearLayoutManager;
        linearLayoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
        this.setLayoutManager(linearLayoutManager);
        return this;
    }

    //VerticalGird
    public PerfectRecyclerView setLayoutManagerVerticalGird(int i) {
        GridLayoutManager gridLayoutManager = new GridLayoutManager(context, i);
        gridLayoutManager.setOrientation(GridLayoutManager.VERTICAL);
        layoutManager = gridLayoutManager;
        this.setLayoutManager(gridLayoutManager);
        return this;
    }

    //HorizontalGird
    public PerfectRecyclerView setLayoutManagerHorizontalGird(int i) {
        GridLayoutManager gridLayoutManager = new GridLayoutManager(context, i);
        gridLayoutManager.setOrientation(GridLayoutManager.HORIZONTAL);
        layoutManager = gridLayoutManager;
        this.setLayoutManager(gridLayoutManager);
        return this;
    }

    //VerticalStaggeredGrid
    public PerfectRecyclerView setLayoutManagerVerticalStaggered(int i) {
        StaggeredGridLayoutManager sgl = new StaggeredGridLayoutManager(i, StaggeredGridLayoutManager.VERTICAL);
        layoutManager = sgl;
        this.setLayoutManager(sgl);
        return this;
    }

    /**
     * 平行瀑布流
     *
     * @param i 垂直每行 i 条
     * @return
     */
    public PerfectRecyclerView setLayoutManagerHorizontalStaggered(int i) {
        StaggeredGridLayoutManager sgl = new StaggeredGridLayoutManager(i, StaggeredGridLayoutManager.HORIZONTAL);
        layoutManager = sgl;
        this.setLayoutManager(sgl);
        return this;
    }

    private LayoutManager layoutManager;

    /**
     * @return LayoutManager
     */
    public LayoutManager getLayoutManager() {
        return layoutManager;
    }


    OnScrollBottom onRollingRequestMore;


    /**
     * 滑动到底部监听
     *
     * @param onBottomLoad
     */
    public void addScrollBottom(OnScrollBottom onBottomLoad) {
        this.onRollingRequestMore = onBottomLoad;
    }

    public interface OnScrollBottom {
        void scrollBottom();
    }

    protected boolean isSlideToBottom() {
        if (computeVerticalScrollExtent() + computeVerticalScrollOffset() >= computeVerticalScrollRange())
            return true;
        return false;
    }

    private class PerfectAdapter extends Adapter<ViewHolder> {

        private Adapter adapter;
        private int Item_Normal = 0;
        private int Item_Header = 1;
        private int Item_Footer = 2;


        public PerfectAdapter(Adapter adapter) {
            this.adapter = adapter;
        }

        @Override
        public void onViewAttachedToWindow(ViewHolder holder) {
            super.onViewAttachedToWindow(holder);
            if (isStaggeredGridLayout(holder)) {
                handleLayoutIfStaggeredGridLayout(holder, holder.getLayoutPosition());
            }
        }

        @Override
        public void onAttachedToRecyclerView(RecyclerView recyclerView) {
            super.onAttachedToRecyclerView(recyclerView);
            LayoutManager manager = recyclerView.getLayoutManager();
            if (manager instanceof GridLayoutManager) {
                final GridLayoutManager gridManager = ((GridLayoutManager) manager);
                gridManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
                    @Override
                    public int getSpanSize(int position) {
                        return getItemViewType(position) == Item_Footer | getItemViewType(position) == Item_Header ? gridManager.getSpanCount() : 1;
                    }
                });
            }
        }

        @Override
        public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            if (viewType == Item_Header) {
                return new PerfectViewHolder(mHeaderView);
            } else if (viewType == Item_Footer) {
                return new PerfectViewHolder(mFooterView);
            } else {
                return adapter.onCreateViewHolder(parent, viewType);
            }
        }

        @Override
        public void onBindViewHolder(ViewHolder holder, int position) {
            int type = getItemViewType(position);
            if (type == Item_Header || type == Item_Footer) {
                return;
            }

            int realPosition = getRealItemPosition(position);
            adapter.onBindViewHolder(holder, realPosition);
        }

        @Override
        public int getItemCount() {
            int itemCount = adapter.getItemCount();
            if (null != mHeaderView) itemCount++;
            if (null != mFooterView) itemCount++;
            return itemCount;
        }

        @Override
        public int getItemViewType(int position) {
            if (null != mHeaderView && position == 0) return Item_Header;
            if (null != mFooterView && position == getItemCount() - 1) return Item_Footer;
            return Item_Normal;
        }

        private boolean isStaggeredGridLayout(ViewHolder holder) {
            ViewGroup.LayoutParams layoutParams = holder.itemView.getLayoutParams();
            if (layoutParams != null && layoutParams instanceof StaggeredGridLayoutManager.LayoutParams) {
                return true;
            }
            return false;
        }

        protected void handleLayoutIfStaggeredGridLayout(ViewHolder holder, int position) {
            if (getItemViewType(position) == Item_Footer | getItemViewType(position) == Item_Header) {
                StaggeredGridLayoutManager.LayoutParams p = (StaggeredGridLayoutManager.LayoutParams) holder.itemView.getLayoutParams();
                p.setFullSpan(true);
            }
        }

        private int getRealItemPosition(int position) {
            if (null != mHeaderView) {
                return position - 1;
            }
            return position;
        }

        private class PerfectViewHolder extends ViewHolder {

            PerfectViewHolder(View itemView) {
                super(itemView);

            }
        }
    }


}
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