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2024-02-26 07:00:02

是否有一个addHeaderView等同的RecyclerView?

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>

头

<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:

当前回答

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 ->

2014-10-26 13:10:33

其他回答

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);
2016-03-05 22:22:12

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。

2014-11-28 21:26:54

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" />

2018-07-16 13:50:19

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。

2020-08-08 12:53:03

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!

2019-08-15 12:39:26

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