RecyclerView多item实现2

banner实现完后，接下来，是五个图标，带文字。

如图： Screenshot_2019-10-24-17-59-27-038_com.li.gohome.png

由于是一排，首先想到的是用LinearLayoutManager并且横向排列。
但是这5个item是平分整个布局，所以可以直接用GridLayoutManager
先add数据：

CommonModelListBean localList = new CommonModelListBean();
localList.setCommonModelListBean(model.getlocalNavList());
localList.setViewType(LOCAL_TYPE);
datas.add(localList);

添加布局：local.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="58dp"
    android:orientation="horizontal"
    android:background="@drawable/shape_radius"
    android:layout_marginLeft="7dp"
    android:layout_marginRight="7dp"
    android:layout_marginTop="4dp">
    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/local_recycler"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

</LinearLayout>

添加item布局：local_item.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

<com.li.gohome.util.CircleImageView
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    android:id="@+id/local_image"
    android:src="@mipmap/ic_launcher"
    android:layout_width="30dp"
    android:layout_height="30dp"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/local_text"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/local_image"
        android:textSize="12dp"
        android:text="ff"
        />
</androidx.constraintlayout.widget.ConstraintLayout>

item布局记得父布局宽度为match_parent。
然后就是设置holder

public class LocalHolder extends RecyclerView.ViewHolder {
        RecyclerView localRecycler;

        public LocalHolder(@NonNull View itemView) {
            super(itemView);
            localRecycler = itemView.findViewById(R.id.local_recycler);
        }
}
else if (viewType == LOCAL_TYPE) {
            return new LocalHolder(LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.local, parent, false));
}

接着在onBindViewHolder里绑定数据：

else if (holder instanceof LocalHolder) {
            CommonModelListBean localBean = (CommonModelListBean) datas.get(position);
            RecyclerView recyclerView = ((LocalHolder) holder).localRecycler;
            recyclerView.setLayoutManager(new GridLayoutManager(context, 5, RecyclerView.VERTICAL, false));
            recyclerView.setAdapter(new LocalAdapter(localBean.getCommonModelListBean(),1));
}

这里布局设置为VERTICAL，并且spanCount设置为5.
再看看LocalAdapter实现。
首先重写一个方法：

public void onAttachedToRecyclerView(@NonNull RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
        RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
        if (layoutManager instanceof GridLayoutManager) {
            GridLayoutManager gridLayoutManager = (GridLayoutManager) layoutManager;
            gridLayoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
                @Override
                public int getSpanSize(int position) {
                    return 1;
                }
            });
        }
}

这里的SpanSize返回1，和上面的spancount结合，代表着一个iten占1/5的位置。
接着就是将HomePageAdapter传来的数据，绑定到item上面。

public class LocalItemHolder extends RecyclerView.ViewHolder {
        CircleImageView image;
        TextView textView;

        public LocalItemHolder(@NonNull View itemView) {
            super(itemView);
            image = itemView.findViewById(R.id.local_image);
            textView = itemView.findViewById(R.id.local_text);
        }
    }
if(itemType == 1) {
            return new LocalItemHolder(LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.local_item, parent, false));
}
if (holder instanceof LocalItemHolder) {
            ((LocalItemHolder) holder).image.setImageURL(localList.get(position).getIcon());
            ((LocalItemHolder) holder).textView.setText(localList.get(position).getTitle());
}

这里为什么有个itemtype呢。。
是因为在主界面，第4个布局，和这个第2个布局，情况很类似，如上图
所以和第二个布局，公用了一个adapter.
这2个布局的区别只有图片不设置圆形，以及有2排。
sub_item.xml:

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <com.li.gohome.util.MyImageView
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    android:id="@+id/sub_image"
    android:src="@mipmap/ic_launcher"
    android:layout_width="18dp"
    android:layout_height="18dp"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/sub_text"
        android:layout_marginTop="3dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/sub_image"
        android:textSize="12dp"
        android:text="ff"
        />
</androidx.constraintlayout.widget.ConstraintLayout>

注意，父布局android:layout_height="wrap_content"，因为有2排，不可以设置为match_parent。
另外自定义了一个imageview用来设置网络图片。
所以其他的都是一样的，只是在初始化adapter的时候，加一个itemtype.
还有就是加了一个分割线设置recyclerView.addItemDecoration(new ItemDecoration());
因为第一排和第二排，中间有一个距离20dp。

public class ItemDecoration extends RecyclerView.ItemDecoration{
        @Override
        public void getItemOffsets(@NonNull Rect outRect, @NonNull View view, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
            super.getItemOffsets(outRect, view, parent, state);
            outRect.set(0, 0, 0, 20);
        }
}

所以将每个item的bottom距离设置为20.
这样就会导致两排都会距离下面20dp。
如果想最后一排不要这个距离，可以将父布局sub的总高度设置小一点，让这个最后一排的高度没有空间。

再来看第三个布局，第三个布局，分3块。所以可以设置一个公用的xml。

grid_item.xml：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="88dp"
    android:orientation="horizontal"
    android:layout_marginLeft="7dp"
    android:layout_marginRight="7dp"
    android:layout_marginTop="4dp"
    android:id="@+id/grid_item_layout">

    <RelativeLayout
        android:layout_width="121dp"
        android:layout_height="88dp"
        >

        <TextView
            android:id="@+id/main_item"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="8dp"
            android:text="kkkk" />

        <ImageView
            android:id="@+id/main_image"
            android:layout_width="121dp"
            android:layout_height="50dp"
            android:layout_alignParentBottom="true"/>


    </RelativeLayout>

    <LinearLayout
        android:layout_width="1dp"
        android:layout_height="88dp"
        android:background="@android:color/white"/>

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="88dp"
        android:layout_weight="1"
        android:orientation="vertical">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            >
            <TextView
                android:id="@+id/item1"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:text="jjj" />
        </RelativeLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="@android:color/white"/>

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1">
            <TextView
                android:id="@+id/item2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:text="hhh" />
        </RelativeLayout>

    </LinearLayout>

    <LinearLayout
        android:layout_width="1dp"
        android:layout_height="88dp"
        android:background="@android:color/white"/>

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="88dp"
        android:layout_weight="1"
        android:orientation="vertical">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            >
            <TextView
                android:id="@+id/item3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:text="jjj" />
        </RelativeLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="@android:color/white"/>

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1">
            <TextView
                android:id="@+id/item4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:text="hhh" />
        </RelativeLayout>
    </LinearLayout>
</LinearLayout>

由于这三个布局的数据，都是GridNav.GridNavItem。
设置一个通用的bean:

public class GridItemBean extends ExampleBaseBean {
    private GridNav.GridNavItem gridItemBean;

    public GridNav.GridNavItem getGridItemBean() {
        return gridItemBean;
    }

    public void setGridItemBean(GridNav.GridNavItem gridItemBean) {
        this.gridItemBean = gridItemBean;
    }
}

添加数据：

//grad_hotel
GridItemBean gradHotel = new GridItemBean();
gradHotel.setGridItemBean(model.getGridnav().getHotel());
gradHotel.setViewType(HOTEL_TYPE);
datas.add(gradHotel);
//grad_flight
GridItemBean gradFlight = new GridItemBean();
gradFlight.setGridItemBean(model.getGridnav().getFlight());
gradFlight.setViewType(FLIGHT_TYPE);
datas.add(gradFlight);
//grad_travel
GridItemBean gradTravel = new GridItemBean();
gradTravel.setGridItemBean(model.getGridnav().getTravel());
gradTravel.setViewType(TRAVEL_TYPE);
datas.add(gradTravel);

设置一个通用的holder

public class GridItemHolder extends RecyclerView.ViewHolder {
        private LinearLayout gridLayout;
        private ImageView mainImage;
        private TextView mainText, Item1, Item2, Item3, Item4;

        public GridItemHolder(@NonNull View itemView) {
            super(itemView);
            gridLayout = itemView.findViewById(R.id.grid_item_layout);
            mainImage = itemView.findViewById(R.id.main_image);
            mainText = itemView.findViewById(R.id.main_item);
            Item1 = itemView.findViewById(R.id.item1);
            Item2 = itemView.findViewById(R.id.item2);
            Item3 = itemView.findViewById(R.id.item3);
            Item4 = itemView.findViewById(R.id.item4);
        }
}

三种type下，都用这个holder.

else if (viewType == HOTEL_TYPE || viewType == FLIGHT_TYPE || viewType == TRAVEL_TYPE) {
            return new GridItemHolder(LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.grid_item, parent, false));
}

接下来绑定数据，这个要考虑通用性：

else if (holder instanceof GridItemHolder) {
            GridItemBean gridItemBean = (GridItemBean) datas.get(position);
            setGridLayoutBG(((GridItemHolder) holder).gridLayout, gridItemBean.getGridItemBean());
            mainItem(((GridItemHolder) holder).mainImage, ((GridItemHolder) holder).mainText, gridItemBean.getGridItemBean().getMainItem());
            gridItem(((GridItemHolder) holder).Item1, ((GridItemHolder) holder).Item2, ((GridItemHolder) holder).Item3,
                    ((GridItemHolder) holder).Item4, gridItemBean.getGridItemBean());
}

这里设置了三个方法，第一个setGridLayoutBG是设置整个item的背景色，

private void setGridLayoutBG(LinearLayout layout, GridNav.GridNavItem gridNavItem) {
        Log.v("mm", gridNavItem.getStartColor());
        GradientDrawable linearDrawableTop = getGrad(Color.parseColor("#" + gridNavItem.getStartColor()), Color.parseColor("#" + gridNavItem.getEndColor()));
        layout.setBackground(linearDrawableTop);
}
public GradientDrawable getGrad(int startColor, int endColor) {
        int[] colors = new int[]{startColor, endColor};
        GradientDrawable linearDrawable = new GradientDrawable();
        linearDrawable.setOrientation(GradientDrawable.Orientation.LEFT_RIGHT);
        linearDrawable.setColors(colors);
        linearDrawable.setGradientType(GradientDrawable.LINEAR_GRADIENT);
        return linearDrawable;
}

第二个方法，设置左边那个大方块：

private void mainItem(ImageView imageView, TextView textView, CommonModel model) {
        Glide.with(context).load(model.getIcon()).into(imageView);
        textView.setText(model.getTitle());
}

第三个方法，设置右边四个小方块：

private void gridItem(TextView item1, TextView item2, TextView item3, TextView item4, GridNav.GridNavItem gridNavItem) {
        item1.setText(gridNavItem.getItem1().getTitle());
        item2.setText(gridNavItem.getItem2().getTitle());
        item3.setText(gridNavItem.getItem3().getTitle());
        item4.setText(gridNavItem.getItem4().getTitle());
}

具体代码如下：
https://github.com/doudousang/recyclerview_items.git

参考网址：
RecyclerView添加分割线最易懂解析
GridLayoutManager setSpanSizeLookup()方法
Android shape gradient背景渐变