我正在寻找一个相当于addHeaderView回收视图。基本上我想有2个按钮的图像被添加到列表视图的标题。有不同的方法来添加一个头视图到回收视图吗?举个例子作为指导会很有帮助

编辑2(增加片段布局):

在添加日志语句之后,getViewType似乎只接收到0的位置。这导致onCreateView只加载一个布局:

10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemCount: 5
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemViewType position: 0
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemViewType position: 0
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> getItemViewType position: 0
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> onCreateViewHolder, viewtype: 0
10-26 16:32:53.766    5449-5449/co.testapp I/logger info﹕ Adapter-> onBindViewHolder, viewType: 0

片段转换来加载CommentFragment:

@Override
public void onPhotoFeedItemClick(View view, int position) {
    if (fragmentManager == null)
        fragmentManager = getSupportFragmentManager();

FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();

    if (view.getId() == R.id.button_comment){
        CommentFragment commentFragment = CommentFragment.newInstance("","", position);
        fragmentTransaction.add(R.id.main_activity, commentFragment,"comment_fragment_tag");
        fragmentTransaction.addToBackStack(Constants.TAG_COMMENTS);
        fragmentTransaction.commit();
    }
}

Fragment的onCreateView:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    View view = inflater.inflate(R.layout.fragment_comment, container, false);
    mRecyclerView = (RecyclerView) view.findViewById(R.id.list_recylclerview);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(_context));
    mRecyclerView.setItemAnimator(new DefaultItemAnimator());
    mAdapter = new CommentAdapter(R.layout.row_list_comments, R.layout.row_header_comments, _context, comments);
    mRecyclerView.setAdapter(mAdapter);
    return view;
}

包含recycleview的片段:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    tools:context="co.testapp.fragments.CommentFragment"
    android:background="@color/white">
        <RelativeLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:orientation="vertical">
            <android.support.v7.widget.RecyclerView
                xmlns:android="http://schemas.android.com/apk/res/android"
                android:id="@+id/list_recylclerview"
                android:layout_width="match_parent"
                android:layout_height="200dp" />
        </RelativeLayout>
</RelativeLayout>

注释行布局:

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent" android:layout_margin="10dp"
    android:background="@color/white">
    <!--Profile Picture-->
    <ImageView
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:id="@+id/profile_picture"
        android:background="@color/blue_testapp"/>
    <!--Name-->
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:text="First Name Last Name"
        android:textSize="16dp"
        android:textColor="@color/blue_testapp"
        android:id="@+id/name_of_poster"
        android:layout_toRightOf="@id/profile_picture"
        />
    <!--Comment-->
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        android:layout_marginTop="-5dp"
        android:text="This is a test comment"
        android:textSize="14dp"
        android:textColor="@color/black"
        android:id="@+id/comment"
        android:layout_below="@id/name_of_poster"
        android:layout_toRightOf="@id/profile_picture"/>
</RelativeLayout>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="300dp"
        android:id="@+id/header_photo"
        android:layout_gravity="center_horizontal"/>
</LinearLayout>

适配器代码(感谢hister让我开始):

public class CommentAdapter extends RecyclerView.Adapter<ViewHolder>{

    private final int rowCardLayout;
    public static Context mContext;
    private final int headerLayout;
    private final String [] comments;
    private static final int HEADER = 0;
    private static final int OTHER = 1;

    public CommentAdapter(int rowCardLayout, int headerLayout, Context context, String [] comments) {
        this.rowCardLayout = rowCardLayout;
        this.mContext = context;
        this.comments = comments;
        this.headerLayout = headerLayout;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        logger.i("onCreateViewHolder, viewtype: " + i); //viewtype always returns 0 so OTHER layout is never inflated
        if (i == HEADER) {
            View v = LayoutInflater.from(viewGroup.getContext()).inflate(headerLayout, viewGroup, false);
            return new ViewHolderHeader(v);
        }
        else if (i == OTHER){
            View v = LayoutInflater.from(viewGroup.getContext()).inflate(rowCardLayout, viewGroup, false);
            return new ViewHolderComments(v);
        }
        else 
          throw new RuntimeException("Could not inflate layout");
    }

    @Override
    public void onBindViewHolder(ViewHolder viewHolder, int i) {
        logger.i("onBindViewHolder, viewType: " + i);

        if (viewHolder instanceof ViewHolderComments)
            ((ViewHolderComments) viewHolder).comment.setText(comments[i].toString());
        if (viewHolder instanceof ViewHolderHeader)
           ((ViewHolderHeader) viewHolder).header.setImageResource(R.drawable.image2);
        else {
            logger.e("no instance of viewholder found");
        }
    }

    @Override
    public int getItemCount() {
        int count = comments.length + 1;
        logger.i("getItemCount: " + count);
        return count;
    }

    @Override
    public int getItemViewType(int position) {
        logger.i("getItemViewType position: " + position);
        if (position == HEADER)
            return HEADER;
        else
            return OTHER;
    }

    public static class ViewHolderComments extends RecyclerView.ViewHolder {
        public TextView comment;
        public ImageView image;

        public ViewHolderComments(View itemView) {
            super(itemView);
            comment = (TextView) itemView.findViewById(R.id.comment);
            image = (ImageView) itemView.findViewById(R.id.image);
        }
    }

    public static class ViewHolderHeader extends RecyclerView.ViewHolder {
        public final ImageView header;

        public ViewHolderHeader(View itemView){
            super(itemView);
            header = (ImageView) itemView.findViewById(R.id.header_photo);
        }
    }
}

使用上面的代码,只有头部布局显示为viewType总是0。它是这样的。如果我强制另一个布局,它看起来像这样:


HeaderView依赖于LayoutManager。默认的layoutmanager都不支持这一点,而且可能不会。ListView中的HeaderView创建了很多复杂性,但没有任何显著的好处。

我建议创建一个基本适配器类,如果提供的话,它可以为header添加项。不要忘记覆盖notify*方法来适当地偏移它们,这取决于header是否存在。


没有像listview.addHeaderView()这样简单的方法,但您可以通过向您的头适配器添加类型来实现这一点。

这里有一个例子

public class HeaderAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private static final int TYPE_HEADER = 0;
    private static final int TYPE_ITEM = 1;
    String[] data;

    public HeaderAdapter(String[] data) {
        this.data = data;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType == TYPE_ITEM) {
            //inflate your layout and pass it to view holder
            return new VHItem(null);
        } else if (viewType == TYPE_HEADER) {
            //inflate your layout and pass it to view holder
            return new VHHeader(null);
        }

        throw new RuntimeException("there is no type that matches the type " + viewType + " + make sure your using types correctly");
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        if (holder instanceof VHItem) {
            String dataItem = getItem(position);
            //cast holder to VHItem and set data
        } else if (holder instanceof VHHeader) {
            //cast holder to VHHeader and set data for header.
        }
    }

    @Override
    public int getItemCount() {
        return data.length + 1;
    }

    @Override
    public int getItemViewType(int position) {
        if (isPositionHeader(position))
            return TYPE_HEADER;

        return TYPE_ITEM;
    }

    private boolean isPositionHeader(int position) {
        return position == 0;
    }

    private String getItem(int position) {
        return data[position - 1];
    }

    class VHItem extends RecyclerView.ViewHolder {
        TextView title;

        public VHItem(View itemView) {
            super(itemView);
        }
    }

    class VHHeader extends RecyclerView.ViewHolder {
        Button button;

        public VHHeader(View itemView) {
            super(itemView);
        }
    }
}

链接到gist ->


基于这篇文章,我创建了一个RecyclerView的子类。支持任意数量的页眉和页脚的适配器。

https://gist.github.com/mheras/0908873267def75dc746

虽然这似乎是一个解决方案,但我也认为这个东西应该由LayoutManager管理。不幸的是,我现在需要它,我没有时间从头开始实现StaggeredGridLayoutManager(甚至也没有从它扩展)。

我还在测试,但如果你想试试也可以。如果你发现有任何问题,请告诉我。


请随意使用我的图书馆,这里有。

它可以让你创建任何RecyclerView的头视图,使用LinearLayoutManager或GridLayoutManager只需一个简单的方法调用。


First - extends RecyclerView.Adapter<RecyclerView.ViewHolder>

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

重载getItemViewTpe方法后 * * *更重要

@Override
public int getItemViewType(int position) {
    return position;
}

方法onCreateViewHolder

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.menu_item, parent, false);
    View header = LayoutInflater.from(parent.getContext()).inflate(R.layout.menu_header_item, parent, false);
    Log.d("onCreateViewHolder", String.valueOf(viewType));

    if (viewType == 0) {
        return new MenuLeftHeaderViewHolder(header, onClickListener);
    } else {
        return new MenuLeftViewHolder(view, onClickListener);
    }
}

方法onBindViewHolder

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
    if (position == 0) {
        MenuHeaderViewHolder menuHeaderViewHolder = (MenuHeaderViewHolder) holder;
        menuHeaderViewHolder.mTitle.setText(sMenuTitles[position]);
        menuHeaderViewHolder.mImage.setImageResource(sMenuImages[position]);
    } else {
        MenuViewHolder menuLeftViewHolder = (MenuLeftViewHolder) holder;
        menuViewHolder.mTitle.setText(sMenuTitles[position]);
        menuViewHolder.mImage.setImageResource(sMenuImages[position]);
    }
}

在finish中实现了ViewHolders类静态

public static class MenuViewHolder extends RecyclerView.ViewHolder 

public static class MenuLeftHeaderViewHolder extends RecyclerView.ViewHolder 

简单和可重复使用的物品装饰

静态标题可以很容易地使用ItemDecoration添加,而不需要任何进一步的更改。

// add the decoration. done.
HeaderDecoration headerDecoration = new HeaderDecoration(/* init */);
recyclerView.addItemDecoration(headerDecoration);

装饰也是可重用的,因为根本不需要修改适配器或RecyclerView。

下面提供的示例代码将需要在顶部添加一个视图,该视图可以像其他任何东西一样膨胀。它可以是这样的:

为什么是静态的?

如果你只是要显示文本和图像,这个解决方案是为你-不可能的用户交互,如按钮或查看分页,因为它只会被绘制到列表的顶部。

空列表处理

如果没有视图来装饰,装饰就画不出来了。您仍然需要自己处理一个空列表。(一种可行的解决方法是向适配器添加一个虚拟项。)

的代码

你可以在GitHub上找到完整的源代码,包括一个Builder来帮助初始化装饰器,或者只是使用下面的代码并将自己的值提供给构造函数。

请确保为您的视图设置正确的layout_height。例如,match_parent可能无法正常工作。

public class HeaderDecoration extends RecyclerView.ItemDecoration {

    private final View mView;
    private final boolean mHorizontal;
    private final float mParallax;
    private final float mShadowSize;
    private final int mColumns;
    private final Paint mShadowPaint;

    public HeaderDecoration(View view, boolean scrollsHorizontally, float parallax, float shadowSize, int columns) {
        mView = view;
        mHorizontal = scrollsHorizontally;
        mParallax = parallax;
        mShadowSize = shadowSize;
        mColumns = columns;

        if (mShadowSize > 0) {
            mShadowPaint = new Paint();
            mShadowPaint.setShader(mHorizontal ?
                    new LinearGradient(mShadowSize, 0, 0, 0,
                            new int[]{Color.argb(55, 0, 0, 0), Color.argb(55, 0, 0, 0), Color.argb(3, 0, 0, 0)},
                            new float[]{0f, .5f, 1f},
                            Shader.TileMode.CLAMP) :
                    new LinearGradient(0, mShadowSize, 0, 0,
                            new int[]{Color.argb(55, 0, 0, 0), Color.argb(55, 0, 0, 0), Color.argb(3, 0, 0, 0)},
                            new float[]{0f, .5f, 1f},
                            Shader.TileMode.CLAMP));
        } else {
            mShadowPaint = null;
        }
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        super.onDraw(c, parent, state);
        // layout basically just gets drawn on the reserved space on top of the first view
        mView.layout(parent.getLeft(), 0, parent.getRight(), mView.getMeasuredHeight());

        for (int i = 0; i < parent.getChildCount(); i++) {
            View view = parent.getChildAt(i);
            if (parent.getChildAdapterPosition(view) == 0) {
                c.save();
                if (mHorizontal) {
                    c.clipRect(parent.getLeft(), parent.getTop(), view.getLeft(), parent.getBottom());
                    final int width = mView.getMeasuredWidth();
                    final float left = (view.getLeft() - width) * mParallax;
                    c.translate(left, 0);
                    mView.draw(c);
                    if (mShadowSize > 0) {
                        c.translate(view.getLeft() - left - mShadowSize, 0);
                        c.drawRect(parent.getLeft(), parent.getTop(), mShadowSize, parent.getBottom(), mShadowPaint);
                    }
                } else {
                    c.clipRect(parent.getLeft(), parent.getTop(), parent.getRight(), view.getTop());
                    final int height = mView.getMeasuredHeight();
                    final float top = (view.getTop() - height) * mParallax;
                    c.translate(0, top);
                    mView.draw(c);
                    if (mShadowSize > 0) {
                        c.translate(0, view.getTop() - top - mShadowSize);
                        c.drawRect(parent.getLeft(), parent.getTop(), parent.getRight(), mShadowSize, mShadowPaint);
                    }
                }
                c.restore();
                break;
            }
        }
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        if (parent.getChildAdapterPosition(view) < mColumns) {
            if (mHorizontal) {
                if (mView.getMeasuredWidth() <= 0) {
                    mView.measure(View.MeasureSpec.makeMeasureSpec(parent.getMeasuredWidth(), View.MeasureSpec.AT_MOST),
                            View.MeasureSpec.makeMeasureSpec(parent.getMeasuredHeight(), View.MeasureSpec.AT_MOST));
                }
                outRect.set(mView.getMeasuredWidth(), 0, 0, 0);
            } else {
                if (mView.getMeasuredHeight() <= 0) {
                    mView.measure(View.MeasureSpec.makeMeasureSpec(parent.getMeasuredWidth(), View.MeasureSpec.AT_MOST),
                            View.MeasureSpec.makeMeasureSpec(parent.getMeasuredHeight(), View.MeasureSpec.AT_MOST));
                }
                outRect.set(0, mView.getMeasuredHeight(), 0, 0);
            }
        } else {
            outRect.setEmpty();
        }
    }
}

请注意:GitHub项目是我个人的游乐场。它没有经过彻底的测试,这就是为什么还没有库。

它能做什么?

ItemDecoration是对列表项的附加绘图。在这种情况下,装饰被绘制到第一项的顶部。

视图被测量和布局,然后被绘制到第一个项目的顶部。如果添加视差效果,它也会被剪辑到正确的边界。


原生API没有这样的“addHeader”特性,但有“addItem”的概念。

我能够在我的FlexibleAdapter项目中包括页眉和页脚扩展的特定功能。我称之为可滚动的页眉和页脚。

以下是它们的工作原理:

可滚动的页眉和页脚是与其他所有项一起滚动的特殊项,但它们不属于主项(业务项),它们总是由适配器在主项旁边处理。这些项持久地位于第一个和最后一个位置。

关于它们有很多可说的,最好阅读详细的维基页面。

此外,FlexibleAdapter允许你创建标题/部分,也可以让他们粘和其他几十个功能,如可扩展的项目,无尽的滚动,UI扩展等…都在一个图书馆里!


你可以使用SectionedRecyclerViewAdapter库来实现它,它有“Sections”的概念,其中Section有一个页眉,页脚和内容(项目列表)。在你的情况下,你可能只需要一个Section,但你可以有很多:

1)创建一个自定义Section类:

class MySection extends StatelessSection {

    List<String> myList = Arrays.asList(new String[] {"Item1", "Item2", "Item3" });

    public MySection() {
        // call constructor with layout resources for this Section header, footer and items 
        super(R.layout.section_header, R.layout.section_footer,  R.layout.section_item);
    }

    @Override
    public int getContentItemsTotal() {
        return myList.size(); // number of items of this section
    }

    @Override
    public RecyclerView.ViewHolder getItemViewHolder(View view) {
        // return a custom instance of ViewHolder for the items of this section
        return new MyItemViewHolder(view);
    }

    @Override
    public void onBindItemViewHolder(RecyclerView.ViewHolder holder, int position) {
        MyItemViewHolder itemHolder = (MyItemViewHolder) holder;

        // bind your view here
        itemHolder.tvItem.setText(myList.get(position));
    }
}

2)为项目创建一个自定义ViewHolder:

class MyItemViewHolder extends RecyclerView.ViewHolder {

    private final TextView tvItem;

    public MyItemViewHolder(View itemView) {
        super(itemView);

        tvItem = (TextView) itemView.findViewById(R.id.tvItem);
    }
}

3)使用SectionedRecyclerViewAdapter设置ReclyclerView

// Create an instance of SectionedRecyclerViewAdapter 
SectionedRecyclerViewAdapter sectionAdapter = new SectionedRecyclerViewAdapter();

MySection mySection = new MySection();

// Add your Sections
sectionAdapter.addSection(mySection);

// Set up your RecyclerView with the SectionedRecyclerViewAdapter
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
recyclerView.setAdapter(sectionAdapter);

还有一个解决方案涵盖了上述所有用例:CompoundAdapter: https://github.com/negusoft/CompoundAdapter-android

您可以创建一个AdapterGroup来保存您的适配器,以及一个带有单个项的适配器,以表示头部。代码简单易读:

AdapterGroup adapterGroup = new AdapterGroup();
adapterGroup.addAdapter(SingleAdapter.create(R.layout.header));
adapterGroup.addAdapter(new CommentAdapter(...));

recyclerView.setAdapter(adapterGroup);

AdapterGroup也允许嵌套,因此对于带有节的适配器,您可以为每个节创建一个AdapterGroup。然后将所有部分放在根适配器组中。


也许http://alexzh.com/tutorials/multiple-row-layouts-using-recyclerview/会有帮助。它只使用RecyclerView和CardView。 这是一个适配器:

public class DifferentRowAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private List<CityEvent> mList;
    public DifferentRowAdapter(List<CityEvent> list) {
        this.mList = list;
    }
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view;
        switch (viewType) {
            case CITY_TYPE:
                view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_city, parent, false);
                return new CityViewHolder(view);
            case EVENT_TYPE:
                view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_event, parent, false);
                return new EventViewHolder(view);
        }
        return null;
    }
    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        CityEvent object = mList.get(position);
        if (object != null) {
            switch (object.getType()) {
                case CITY_TYPE:
                    ((CityViewHolder) holder).mTitle.setText(object.getName());
                    break;
                case EVENT_TYPE:
                    ((EventViewHolder) holder).mTitle.setText(object.getName());
                    ((EventViewHolder) holder).mDescription.setText(object.getDescription());
                    break;
            }
        }
    }
    @Override
    public int getItemCount() {
        if (mList == null)
            return 0;
        return mList.size();
    }
    @Override
    public int getItemViewType(int position) {
        if (mList != null) {
            CityEvent object = mList.get(position);
            if (object != null) {
                return object.getType();
            }
        }
        return 0;
    }
    public static class CityViewHolder extends RecyclerView.ViewHolder {
        private TextView mTitle;
        public CityViewHolder(View itemView) {
            super(itemView);
            mTitle = (TextView) itemView.findViewById(R.id.titleTextView);
        }
    }
    public static class EventViewHolder extends RecyclerView.ViewHolder {
        private TextView mTitle;
        private TextView mDescription;
        public EventViewHolder(View itemView) {
            super(itemView);
            mTitle = (TextView) itemView.findViewById(R.id.titleTextView);
            mDescription = (TextView) itemView.findViewById(R.id.descriptionTextView);
        }
    }
}

这是一个实体:

public class CityEvent {
    public static final int CITY_TYPE = 0;
    public static final int EVENT_TYPE = 1;
    private String mName;
    private String mDescription;
    private int mType;
    public CityEvent(String name, String description, int type) {
        this.mName = name;
        this.mDescription = description;
        this.mType = type;
    }
    public String getName() {
        return mName;
    }
    public void setName(String name) {
        this.mName = name;
    }
    public String getDescription() {
        return mDescription;
    }
    public void setDescription(String description) {
        this.mDescription = description;
    }
    public int getType() {
        return mType;
    }
    public void setType(int type) {
        this.mType = type;
    }
}

这里有一些物品装饰

public class HeaderItemDecoration extends RecyclerView.ItemDecoration {

private View customView;

public HeaderItemDecoration(View view) {
    this.customView = view;
}

@Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
    super.onDraw(c, parent, state);
    customView.layout(parent.getLeft(), 0, parent.getRight(), customView.getMeasuredHeight());
    for (int i = 0; i < parent.getChildCount(); i++) {
        View view = parent.getChildAt(i);
        if (parent.getChildAdapterPosition(view) == 0) {
            c.save();
            final int height = customView.getMeasuredHeight();
            final int top = view.getTop() - height;
            c.translate(0, top);
            customView.draw(c);
            c.restore();
            break;
        }
    }
}

@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
    if (parent.getChildAdapterPosition(view) == 0) {
        customView.measure(View.MeasureSpec.makeMeasureSpec(parent.getMeasuredWidth(), View.MeasureSpec.AT_MOST),
                View.MeasureSpec.makeMeasureSpec(parent.getMeasuredHeight(), View.MeasureSpec.AT_MOST));
        outRect.set(0, customView.getMeasuredHeight(), 0, 0);
    } else {
        outRect.setEmpty();
    }
}
}      

你可以把你的头和你的RecyclerView放在NestedScrollView中:

<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        >

        <include
            layout="@layout/your_header"/>

        <android.support.v7.widget.RecyclerView
            android:id="@+id/list_recylclerview"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />

    </LinearLayout>

</android.support.v4.widget.NestedScrollView>

为了让滚动正常工作,你需要在RecyclerView上禁用嵌套滚动:

myRecyclerView.setNestedScrollingEnabled(false);

将向您展示如何在Recycler视图中创建带有项目的header。

步骤1-在gradle文件中添加依赖项。

compile 'com.android.support:recyclerview-v7:23.2.0'
// CardView
compile 'com.android.support:cardview-v7:23.2.0'

卡片视图用于装饰目的。

Step2-制作三个xml文件。 一个是主要活动。其次是标题布局。第三为列表项布局。

activity_main.xml

<android.support.v7.widget.RecyclerView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/my_recycler_view"
    android:scrollbars="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

header.xml

<android.support.v7.widget.CardView
    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"
    app:cardElevation="2dp">

    <TextView
        android:id="@+id/txtHeader"
        android:gravity="center"
        android:textColor="#000000"
        android:textSize="@dimen/abc_text_size_large_material"
        android:background="#DCDCDC"
        android:layout_width="match_parent"
        android:layout_height="50dp" />

</android.support.v7.widget.CardView>

list.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    xmlns:app="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <android.support.v7.widget.CardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:cardElevation="1dp">

        <TextView
            android:id="@+id/txtName"
            android:text="abc"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </android.support.v7.widget.CardView>

</LinearLayout>

步骤3-创建三个bean类。

Header.java

public class Header extends ListItem {
    private String header;

    public String getHeader() {
        return header;
    }
    public void setHeader(String header) {
        this.header = header;
    }
}

ContentItem.java

public class ContentItem extends ListItem {

    private String name;
    private String rollnumber;

    @Override
    public String getName() {
        return name;
    }

    @Override
    public void setName(String name) {
        this.name = name;
    }

    public String getRollnumber() {
        return rollnumber;
    }

    public void setRollnumber(String rollnumber) {
        this.rollnumber = rollnumber;
    }
}

ListItem.java

public class ListItem {
    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    private int id;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }
}

步骤4-创建一个名为MyRecyclerAdapter.java的适配器

public class MyRecyclerAdapter extends  RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private static final int TYPE_HEADER = 0;
    private static final int TYPE_ITEM = 1;

    //Header header;
    List<ListItem> list;
    public MyRecyclerAdapter(List<ListItem> headerItems) {
        this.list = headerItems;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        if (viewType == TYPE_HEADER) {
            View v = inflater.inflate(R.layout.header, parent, false);
            return  new VHHeader(v);
        } else {
            View v = inflater.inflate(R.layout.list, parent, false);
            return new VHItem(v);
        }
        throw new IllegalArgumentException();
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        if (holder instanceof VHHeader) {
           // VHHeader VHheader = (VHHeader)holder;
            Header  currentItem = (Header) list.get(position);
            VHHeader VHheader = (VHHeader)holder;
            VHheader.txtTitle.setText(currentItem.getHeader());
        } else if (holder instanceof VHItem) 
            ContentItem currentItem = (ContentItem) list.get(position);
            VHItem VHitem = (VHItem)holder;
            VHitem.txtName.setText(currentItem.getName());
        }
    }

    @Override
    public int getItemViewType(int position) {
        if (isPositionHeader(position))
            return TYPE_HEADER;
        return TYPE_ITEM;
    }

    private boolean isPositionHeader(int position) {
        return list.get(position) instanceof Header;
    }

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

    class VHHeader extends RecyclerView.ViewHolder{
        TextView txtTitle;
        public VHHeader(View itemView) {
            super(itemView);
            this.txtTitle = (TextView) itemView.findViewById(R.id.txtHeader);
        }
    }
    class VHItem extends RecyclerView.ViewHolder{
        TextView txtName;
        public VHItem(View itemView) {
            super(itemView);
            this.txtName = (TextView) itemView.findViewById(R.id.txtName);
        }
    }
}

步骤5 - 在MainActivity中添加以下代码:

public class MainActivity extends AppCompatActivity {
    RecyclerView recyclerView;
    List<List<ListItem>> arraylist;
    MyRecyclerAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        recyclerView = (RecyclerView)findViewById(R.id.my_recycler_view);
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        adapter = new MyRecyclerAdapter(getList());
        recyclerView.setLayoutManager(linearLayoutManager);
        recyclerView.setAdapter(adapter);
    }

    private ArrayList<ListItem> getList() {
        ArrayList<ListItem> arrayList = new ArrayList<>();
        for(int j = 0; j <= 4; j++) {
            Header header = new Header();
            header.setHeader("header"+j);
            arrayList.add(header);
            for (int i = 0; i <= 3; i++) {
                ContentItem item = new ContentItem();
                item.setRollnumber(i + "");
                item.setName("A" + i);
                arrayList.add(item);
            }
        }
        return arrayList;
    }

}

函数getList()动态地为标题和列表项生成数据。


你可以创建addHeaderView并使用

adapter.addHeaderView(视图)。

这段代码为多个头文件构建addHeaderView。 头文件应该有:

android: layout_height = " wrap_content "

public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private static final int TYPE_ITEM = -1;
    public class MyViewSHolder extends RecyclerView.ViewHolder {
        public MyViewSHolder (View view) {
            super(view);
        }
        // put you code. for example:
        View mView;
        ...
    }

    public class ViewHeader extends RecyclerView.ViewHolder {
        public ViewHeader(View view) {
            super(view);
        }
    }

    private List<View> mHeaderViews = new ArrayList<>();
    public void addHeaderView(View headerView) {
        mHeaderViews.add(headerView);
    }

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

    @Override
    public int getItemViewType(int position) {
        if (mHeaderViews.size() > position) {
            return position;
        }

        return TYPE_ITEM;
    }
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType != TYPE_ITEM) {
            //inflate your layout and pass it to view holder
            return new ViewHeader(mHeaderViews.get(viewType));
        }
        ...
    }
    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int basePosition1) {
        if (holder instanceof ViewHeader) {
            return;
        }
        int basePosition = basePosition1 -  mHeaderViews.size();
        ...
    }
}

出于个人目的,我在@hister的基础上做了一个实现,但使用了继承。

我在抽象超类HeadingableRecycleAdapter中隐藏了实现细节机制(如向itemCount中添加1,从position中减去1),通过 实现所需的方法从适配器像onBindViewHolder, getItemViewType和getItemCount,使该方法最终,并提供新的方法与隐藏的逻辑客户端:

onAddViewHolder (RecyclerView。ViewHolder holder, int position), onCreateViewHolder (ViewGroup父), itemCount ()

这里是HeadingableRecycleAdapter类和一个客户端。我留下的标题布局有点硬编码,因为它符合我的需要。

public abstract class HeadingableRecycleAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    private static final int HEADER_VIEW_TYPE = 0;

    @LayoutRes
    private int headerLayoutResource;
    private String headerTitle;
    private Context context;

    public HeadingableRecycleAdapter(@LayoutRes int headerLayoutResourceId, String headerTitle, Context context) {
        this.headerLayoutResource = headerLayoutResourceId;
        this.headerTitle = headerTitle;
        this.context = context;
    }

    public Context context() {
        return context;
    }

    @Override
    public final RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType == HEADER_VIEW_TYPE) {
            return new HeaderViewHolder(LayoutInflater.from(context).inflate(headerLayoutResource, parent, false));
        }
        return onCreateViewHolder(parent);
    }

    @Override
    public final void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        int viewType = getItemViewType(position);
        if (viewType == HEADER_VIEW_TYPE) {
            HeaderViewHolder vh = (HeaderViewHolder) holder;
            vh.bind(headerTitle);
        } else {
            onAddViewHolder(holder, position - 1);
        }
    }

    @Override
    public final int getItemViewType(int position) {
        return position == 0 ? 0 : 1;
    }

    @Override
    public final int getItemCount() {
        return itemCount() + 1;
    }

    public abstract int itemCount();

    public abstract RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent);

    public abstract void onAddViewHolder(RecyclerView.ViewHolder holder, int position);

}



@PerActivity
public class IngredientsAdapter extends HeadingableRecycleAdapter {
    public static final String TITLE = "Ingredients";
    private List<Ingredient> itemList;


    @Inject
    public IngredientsAdapter(Context context) {
        super(R.layout.layout_generic_recyclerview_cardified_header, TITLE, context);
    }

    public void setItemList(List<Ingredient> itemList) {
        this.itemList = itemList;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent) {
        return new ViewHolder(LayoutInflater.from(context()).inflate(R.layout.item_ingredient, parent, false));
    }

    @Override
    public void onAddViewHolder(RecyclerView.ViewHolder holder, int position) {
        ViewHolder vh = (ViewHolder) holder;
        vh.bind(itemList.get(position));
    }

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

    private String getQuantityFormated(double quantity, String measure) {
        if (quantity == (long) quantity) {
            return String.format(Locale.US, "%s %s", String.valueOf(quantity), measure);
        } else {
            return String.format(Locale.US, "%.1f %s", quantity, measure);
        }
    }


    class ViewHolder extends RecyclerView.ViewHolder {
        @BindView(R.id.text_ingredient)
        TextView txtIngredient;

        ViewHolder(View itemView) {
            super(itemView);
            ButterKnife.bind(this, itemView);
        }

        void bind(Ingredient ingredient) {
            String ingredientText = ingredient.getIngredient();
            txtIngredient.setText(String.format(Locale.US, "%s %s ", getQuantityFormated(ingredient.getQuantity(),
                    ingredient.getMeasure()), Character.toUpperCase(ingredientText.charAt(0)) +
                    ingredientText
                            .substring(1)));
        }
    }
}

也许将header和recyclerview包装成一个coordinatorlayout:

<android.support.design.widget.CoordinatorLayout
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">

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:elevation="0dp">

    <View
        android:id="@+id/header"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_scrollFlags="scroll" />

</android.support.design.widget.AppBarLayout>

<android.support.v7.widget.RecyclerView
    android:id="@+id/list"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior" />


已经过去几年了,但以防有人以后读到这篇文章……

使用上面的代码,只有头部布局显示为viewType总是0。

问题在于常量声明:

private static final int HEADER = 0;
private static final int OTHER = 0;  <== bug 

如果您将它们都声明为零,那么您将始终得到零!


我实现了EC84B4答案中提出的相同方法,但我抽象了RecycleViewAdapter,并通过接口使其易于重用。

所以为了使用我的方法,你应该添加以下基类和接口到你的项目:

1)为适配器提供数据的接口(泛型类型T的集合,以及泛型类型P的附加参数(如果需要))

public interface IRecycleViewListHolder<T,P>{
            P getAdapterParameters();
            T getItem(int position);
            int getSize();
    }

2)用于绑定您的项目(标题/项目)的工厂:

public interface IViewHolderBinderFactory<T,P> {
        void bindView(RecyclerView.ViewHolder holder, int position,IRecycleViewListHolder<T,P> dataHolder);
}

3) viewHolders的工厂(头/项):

public interface IViewHolderFactory {
    RecyclerView.ViewHolder provideInflatedViewHolder(int viewType, LayoutInflater layoutInflater,@NonNull ViewGroup parent);
}

4) Adapter with Header的基类:

public class RecycleViewHeaderBased<T,P> extends RecyclerView.Adapter<RecyclerView.ViewHolder>{

    public final static int HEADER_TYPE = 1;
    public final static int ITEM_TYPE = 0;
    private final IRecycleViewListHolder<T, P> dataHolder;
    private final IViewHolderBinderFactory<T,P> binderFactory;
    private final IViewHolderFactory viewHolderFactory;

    public RecycleViewHeaderBased(IRecycleViewListHolder<T,P> dataHolder, IViewHolderBinderFactory<T,P> binderFactory, IViewHolderFactory viewHolderFactory) {
        this.dataHolder = dataHolder;
        this.binderFactory = binderFactory;
        this.viewHolderFactory = viewHolderFactory;
    }

    @NonNull
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
        return viewHolderFactory.provideInflatedViewHolder(viewType,layoutInflater,parent);
    }

    @Override
    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
            binderFactory.bindView(holder, position,dataHolder);
    }

    @Override
    public int getItemViewType(int position) {
        if(position == 0)
            return HEADER_TYPE;
        return ITEM_TYPE;
    }

    @Override
    public int getItemCount() {
        return dataHolder.getSize()+1;
    }
}

使用的例子:

1) irecycleviewlisholder实现:

public class AssetTaskListData implements IRecycleViewListHolder<Map.Entry<Integer, Integer>, GroupedRecord> {
    private List<Map.Entry<Integer, Integer>> assetCountList;
    private GroupedRecord record;

    public AssetTaskListData(Map<Integer, Integer> assetCountListSrc, GroupedRecord record) {
        this.assetCountList =  new ArrayList<>();
        for(Object  entry: assetCountListSrc.entrySet().toArray()){
            Map.Entry<Integer,Integer> entryTyped = (Map.Entry<Integer,Integer>)entry;
            assetCountList.add(entryTyped);
        }
        this.record = record;
    }

    @Override
    public GroupedRecord getAdapterParameters() {
        return record;
    }

    @Override
    public Map.Entry<Integer, Integer> getItem(int position) {
        return assetCountList.get(position-1);
    }

    @Override
    public int getSize() {
        return assetCountList.size();
    }
}

2) IViewHolderBinderFactory实现:

public class AssetTaskListBinderFactory implements IViewHolderBinderFactory<Map.Entry<Integer, Integer>, GroupedRecord> {
    @Override
    public void bindView(RecyclerView.ViewHolder holder, int position, IRecycleViewListHolder<Map.Entry<Integer, Integer>, GroupedRecord> dataHolder) {
        if (holder instanceof AssetItemViewHolder) {
            Integer assetId = dataHolder.getItem(position).getKey();
            Integer assetCount = dataHolder.getItem(position).getValue();
            ((AssetItemViewHolder) holder).bindItem(dataHolder.getAdapterParameters().getRecordId(), assetId, assetCount);
        } else {
            ((AssetHeaderViewHolder) holder).bindItem(dataHolder.getAdapterParameters());
        }
    }
}

3) IViewHolderFactory实现:

public class AssetTaskListViewHolderFactory implements IViewHolderFactory {
    private IPropertyTypeIconMapper iconMapper;
    private ITypeCaster caster;

    public AssetTaskListViewHolderFactory(IPropertyTypeIconMapper iconMapper, ITypeCaster caster) {
        this.iconMapper = iconMapper;
        this.caster = caster;
    }

    @Override
    public RecyclerView.ViewHolder provideInflatedViewHolder(int viewType, LayoutInflater layoutInflater, @NonNull ViewGroup parent) {
        if (viewType == RecycleViewHeaderBased.HEADER_TYPE) {
            AssetBasedHeaderItemBinding item = DataBindingUtil.inflate(layoutInflater, R.layout.asset_based_header_item, parent, false);
            return new AssetHeaderViewHolder(item.getRoot(), item, caster);
        }
        AssetBasedListItemBinding item = DataBindingUtil.inflate(layoutInflater, R.layout.asset_based_list_item, parent, false);
        return new AssetItemViewHolder(item.getRoot(), item, iconMapper, parent.getContext());
    }
}

4)派生适配器

public class AssetHeaderTaskListAdapter extends RecycleViewHeaderBased<Map.Entry<Integer, Integer>, GroupedRecord> {
   public AssetHeaderTaskListAdapter(IRecycleViewListHolder<Map.Entry<Integer, Integer>, GroupedRecord> dataHolder,
                                      IViewHolderBinderFactory binderFactory,
                                      IViewHolderFactory viewHolderFactory) {
        super(dataHolder, binderFactory, viewHolderFactory);
    }
}

5)实例化适配器类:

private void setUpAdapter() {
        Map<Integer, Integer> objectTypesCountForGroupedTask = groupedTaskRepository.getObjectTypesCountForGroupedTask(this.groupedRecordId);
        AssetTaskListData assetTaskListData = new AssetTaskListData(objectTypesCountForGroupedTask, getGroupedRecord());
        adapter = new AssetHeaderTaskListAdapter(assetTaskListData,new AssetTaskListBinderFactory(),new AssetTaskListViewHolderFactory(iconMapper,caster));
        assetTaskListRecycler.setAdapter(adapter);
    }

注:AssetItemViewHolder, AssetBasedListItemBinding等,我的应用程序自己的结构应该由你自己交换,为你自己的目的。


如果您想在多个列表之间轻松重用头文件,请查看recyclerview库的1.2.0版本。它引入了ConcatAdapter类,该类将多个适配器连接成一个适配器。因此,你可以创建一个头适配器,并轻松地将它与任何其他适配器结合起来,比如:

myRecyclerView.adapter = ConcatAdapter(headerAdapter, listAdapter)

公告文章包含了如何使用ConcatAdapter在页眉和页脚中显示加载进度的示例。

当我发布这个答案的时候,这个库的1.2.0版本还在alpha阶段,所以api可能会改变。您可以在这里查看状态。


我知道这是一个老问题,但我还是想提供一个答案。

这里有一个ConcatAdapter(文档)可以为您解决这个问题。 你所要做的就是定义你的头视图布局,并用一个项目创建一个虚拟适配器 在Kotlin中,它只需要几行

class HeaderAdapter(private val inflater: LayoutInflater) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
    
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int) = object : RecyclerView.ViewHolder(inflater.inflate(yourViewLayoutId, parent, false)) {}

    override fun onBindViewHolder(viewHolder: RecyclerView.ViewHolder, position: Int) {}

    override fun getItemCount() = 1
}

在此之后,您所要做的就是将头适配器和原始适配器添加到ConcatAdapter

recyclerView.adapter = ConcatAdapter(headerAdapter, adapter)

有关更多详细信息和高级案例,请参阅文档。


这就是我的解决方案,它使用了一个抽象类来扩展适配器

abstract class HeaderAdapter<T : RecyclerView.ViewHolder>(headerView: View)
    : RecyclerView.Adapter<RecyclerView.ViewHolder>() {

    var headerView: View = headerView
        set(value) {
            notifyItemChanged(HEADER_POSITION)
            field = value
        }
    
    companion object {
        const val TYPE_HEADER = -1
        const val HEADER_POSITION = 0
    }

    abstract val itemCountWithoutHeader: Int
    abstract fun getViewHolder(parent: ViewGroup, viewType: Int): T
    abstract fun onBindItemViewHolder(holder: T, position: Int)

    open fun getItemsItemViewType(position: Int): Int {
        return super.getItemViewType(position)
    }

    final override fun getItemCount(): Int = itemCountWithoutHeader + 1

    final override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
        return if (viewType == TYPE_HEADER) HeaderHolder(headerView) else getViewHolder(parent, viewType)
    }

    final override fun getItemViewType(position: Int): Int {
        return if (position == HEADER_POSITION) TYPE_HEADER else getItemsItemViewType(position)
    }

    final override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
        if (position != HEADER_POSITION) onBindItemViewHolder(holder as T, position-1)
    }

    class HeaderHolder(itemView: View) : RecyclerView.ViewHolder(itemView)
}