RecyclerView无法显示

时间:2014-11-21 16:49:25

标签: android android-recyclerview

我有一个不显示任何项目的RecyclerView。最初它是空的,但后来我添加了项目并调用notifyDatasetChanged()。调用getItemCount()并返回25,onBindViewHolder被调用3次并正确设置视图。

public AlbumListAdapter(FacebookActivity activity, long pageId, OnItemClickListener listener){
    this.listener = listener;
    this.inflater = LayoutInflater.from(activity);
    this.service = new PagedGraphService<Album>(String.format("https://graph.facebook.com/%d/albums", pageId),
            new PagedGraphService.ServiceUpdateListener() {
        @Override
        public void dataUpdated() {
            notifyDataSetChanged();
        }

        @Override
        public void endReached() {

        }
    },
    new TypeToken<PagedGraphService.GraphResponse<Album>>(){}.getType());
}

@Override
public AlbumHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    return new AlbumHolder(inflater.inflate(R.layout.photo_album_list_card, viewGroup, false));
}

@Override
public void onBindViewHolder(AlbumHolder viewHolder, int i) {
    viewHolder.setAlbum(service.get(i));
}

@Override
public int getItemCount() {
    return service.getLoadedCount();
}

它的要点。该服务包含一个专辑列表,并通过调用dataUpdated()和endReached()通知适配器更改。

更多代码:

@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    RecyclerView view = (RecyclerView) inflater.inflate(R.layout.recycler, container, false);
    view.setLayoutManager(new LinearLayoutManager(activity, LinearLayoutManager.VERTICAL, false));
    view.setHasFixedSize(false);
    AlbumListAdapter adapter = new AlbumListAdapter(activity, FacebookActivity.PSM_PAGE_ID, this);
    view.setAdapter(adapter);
    return view;
}

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

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

更多代码:

活动布局

<?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="match_parent">

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

<FrameLayout
    android:id="@+id/content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

</LinearLayout>

列出项目布局:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">

<TextView
    android:id="@+id/album_list_title"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

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

列表布局:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">

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

我一直在把代码戳了几个小时,我不知道它为什么不起作用

1 个答案:

答案 0 :(得分:21)

我是个白痴。

<?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="match_parent">

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

<FrameLayout
    android:id="@+id/content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

</LinearLayout>

LinearLayout的默认方向是水平的,工具栏的宽度是match_parent,因此我的内容不在屏幕上。这可能是Android上最流行的错误之一,这就是为什么你会收到警告,但是include必须隐藏它。