Android RecycleView实现不同样式Item样式效果完美解决

       在我们开发过程中经常会遇到需要我们展示不同样式列表的情况，通常我们都会使用ListView展示列表，然后实现BaseAdapter两个方法，即：getViewTypeCount() 和 getItemViewType(int position)即可实现

不过在Android Nougat Google发布了RecycleView之后，大家都纷纷弃ListView ,GridView，而使用RecycleView。所以今天我们写一个RecycleView实现不同Item条目样式的案例。

RecycleView和RecycleViewAdapter使用步骤:

1,初始化RecycleView及相关设置

     mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        //设置适配器管理器：LinearLayoutManager GridLayoutManager StaggeredGridLayoutManager(瀑布流)，
        mRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
        //添加分割线
        mRecyclerView.addItemDecoration(new RecycleItemDecoration(context, RecycleItemDecoration.VERTICAL_LIST));

2,设置适配器和添加数据

<span style="white-space:pre">	</span>mRecyclerView.setAdapter(new RecycleAdapter(context, initData()));

 private List<Bean> initData() {

        List<Bean> mData = new ArrayList<>();
        for (int i = 'A'; i < 'Z'; i++) {

            Bean bean = new Bean();
            bean.setText((char) i + "");
            int type = i % 3;
            if (type == 0) {
                bean.setType(0);
            } else if (type == 1) {
                bean.setType(1);
            } else if (type == 2) {
                bean.setType(2);
            }

            mData.add(bean);
        }

        return mData;
    }

3，实现RecycleViewAdapter适配器并实现所需方法

通常实现常用列表样式只需要实现两个方法即可：

<span style="white-space:pre">	</span>public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)

用来创建ViewHolder并将item布局添加ViewHolder中

 <span style="white-space:pre">	</span>public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position)

获取已绑定的ViewHolder对象并进行数据填充

而我们使用RecycleView实现不同Item样式的展示，同ListVIew一样，RecycleView也给我们提供了类似的方法，

 <span style="white-space:pre">	</span>public int getItemViewType(int position) 

获取指定苏索引条目的样式类型，返回值即为当前条目样式的类型（我总感觉应该是setItemViewType比较恰当）

通过这三部我们就基本可以使用RecycleView和RecycleAdapter实现列表和多种Item样式布局展示。下面我们展示详细代码：

/**
 * 作    者 ：丁广帅
 * 创建日期 ：2016/9/29 10:30
 * 描   述 ：
 */

public class PerfertectFg extends BaseFragment {

    @SuppressLint("ValidFragment")
    public PerfertectFg(String tabNames, int tabIcons) {
        super(tabNames, tabIcons);
    }

    public PerfertectFg() {
    }


    private RecyclerView mRecyclerView;
    private Context context;

    @Override
    protected void onCreateViewLazy(Bundle savedInstanceState) {
        super.onCreateViewLazy(savedInstanceState);
        setContentView(R.layout.child_three);

        context = getContext();

        mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        //设置适配器管理器：LinearLayoutManager GridLayoutManager StaggeredGridLayoutManager(瀑布流)，
        mRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
        //添加分割线
        mRecyclerView.addItemDecoration(new RecycleItemDecoration(context, RecycleItemDecoration.VERTICAL_LIST));

        mRecyclerView.setAdapter(new RecycleAdapter(context, initData()));

    }

    private List<Bean> initData() {

        List<Bean> mData = new ArrayList<>();
        for (int i = 'A'; i < 'Z'; i++) {

            Bean bean = new Bean();
            bean.setText((char) i + "");
            int type = i % 3;
            if (type == 0) {
                bean.setType(0);
            } else if (type == 1) {
                bean.setType(1);
            } else if (type == 2) {
                bean.setType(2);
            }

            mData.add(bean);
        }
        return mData;
    }
}

借鉴鸿神的分割线样式：Android RecyclerView 使用完全解析 体验艺术般的控件

public class RecycleItemDecoration extends RecyclerView.ItemDecoration {


    /**
     * 读取attr资源
     */
    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;

    //分割线高度
    private int mOrientation;

    public RecycleItemDecoration(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);
        }
    }


    /**
     * 绘制竖直方向分割线
     *
     * @param c
     * @param 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 < childCount; i++) {
            final View child = parent.getChildAt(i);
            android.support.v7.widget.RecyclerView v = new android.support.v7.widget.RecyclerView(parent.getContext());
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int top = child.getBottom() + params.bottomMargin;
            final int bottom = top + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    /**
     * 绘制水平方向分割线
     *
     * @param c
     * @param parent
     */
    public void drawHorizontal(Canvas c, RecyclerView parent) {
        final int top = parent.getPaddingTop();
        final int bottom = parent.getHeight() - parent.getPaddingBottom();

        final int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = parent.getChildAt(i);
            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child
                    .getLayoutParams();
            final int left = child.getRight() + params.rightMargin;
            final int right = left + mDivider.getIntrinsicHeight();
            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {
        //区别类型将分割线设置在下方和右方
        if (mOrientation == VERTICAL_LIST) {
            outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
        } else {
            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);
        }
    }

}

d RecycleView适配器实现，需要我们注意的一点是如果仅有一种Item样式RecycleAdapter的泛型我们直接写成自定义ViewHolder即可。如果是多种Item样式的话，RecycleAdapter泛型必须为RecycleView.ViewHolder，然后再进行强转

((ViewHolderA) holder).text.setText(mData.get(position).getText() + "------样式一");

/**
 * 作    者 ：丁广帅
 * 创建日期 ：2016/10/14 14:26
 * 描   述 ：
 */

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

    /**
     * RecycleViewAdapter 要素点：
     * <p/>
     * 1，ViewHolder必须继承RecyclerView.ViewHolder
     * 2，RecycleView.Adapter的泛型为自定义ViewHolder
     */


    private List<Bean> mData;
    private Context context;

    public enum Item_Type {
        RECYCLEVIEW_ITEM_TYPE_1,
        RECYCLEVIEW_ITEM_TYPE_2,
        RECYCLEVIEW_ITEM_TYPE_3
    }

    public RecycleAdapter(Context context, List<Bean> mData) {
        this.mData = mData;
        this.context = context;
    }


    /**
     * 创建ViewHolder
     *
     * @param parent
     * @param viewType :不同ItemView的类型
     * @return
     */
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        if (viewType == Item_Type.RECYCLEVIEW_ITEM_TYPE_1.ordinal()) {
            View mView = LayoutInflater.from(context).inflate(R.layout.recycle_item_a, null);
            ViewHolderA viewHolder = new ViewHolderA(mView);
            return viewHolder;

        } else if (viewType == Item_Type.RECYCLEVIEW_ITEM_TYPE_2.ordinal()) {

            View mView = LayoutInflater.from(context).inflate(R.layout.recycle_item_b, null);
            ViewHolderB viewHolder = new ViewHolderB(mView);
            return viewHolder;
        } else if (viewType == Item_Type.RECYCLEVIEW_ITEM_TYPE_3.ordinal()) {
            View mView = LayoutInflater.from(context).inflate(R.layout.recycle_item_c, null);
            ViewHolderC viewHolder = new ViewHolderC(mView);
            return viewHolder;
        }

        return null;
    }


    /**
     * 绑定数据：可以直接拿到已经绑定控件的Viewholder对象
     *
     * @param holder
     * @param position
     */
    @Override
    public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {

        if (holder instanceof ViewHolderA) {
            ((ViewHolderA) holder).text.setText(mData.get(position).getText() + "------样式一");
        } else if (holder instanceof ViewHolderB) {
            ((ViewHolderB) holder).text.setText(mData.get(position).getText() + "------样式二");
        } else if (holder instanceof ViewHolderC) {
            ((ViewHolderC) holder).text.setText(mData.get(position).getText() + "------样式三");
        }

    }


    //返回值赋值给onCreateViewHolder的参数 viewType
    @Override
    public int getItemViewType(int position) {

        if (mData.get(position).getType() == 0) {
            return Item_Type.RECYCLEVIEW_ITEM_TYPE_1.ordinal();
        } else if (mData.get(position).getType() == 1) {
            return Item_Type.RECYCLEVIEW_ITEM_TYPE_2.ordinal();
        } else if (mData.get(position).getType() == 2) {
            return Item_Type.RECYCLEVIEW_ITEM_TYPE_3.ordinal();
        }
        return -1;
    }

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

    class ViewHolderA extends RecyclerView.ViewHolder {
        public TextView text;

        public ViewHolderA(View itemView) {
            super(itemView);
            text = (TextView) itemView.findViewById(R.id.text);
        }
    }


    class ViewHolderB extends RecyclerView.ViewHolder {

        public TextView text;

        public ViewHolderB(View itemView) {
            super(itemView);
            text = (TextView) itemView.findViewById(R.id.text);
        }
    }

    class ViewHolderC extends RecyclerView.ViewHolder {

        public TextView text;

        public ViewHolderC(View itemView) {
            super(itemView);
            text = (TextView) itemView.findViewById(R.id.text);
        }
    }


}

最后还是建议大家以后尽量使用RecycleView来替代ListVIew和GridView！！！

下载链接：http://download.youkuaiyun.com/detail/ding_gc/9655977