我将尝试在recycler view中展示字符串列表,但出现了一些问题。它没有显示任何内容。
我不知道为什么它不起作用,这不是我第一次使用它,通常我会使用firebase recycler来实现。
以下是我的代码:
rvTypeMusic = (RecyclerView)findViewById(R.id.rvMusicType);
ArrayList<String> songs = new ArrayList<String>();
songs.add("PHP");
songs.add("C#");
songs.add("Java");
songs.add("JavaScript");
songs.add("Android");
adapter = new TypeMusicListAdapter(this,songs);
rvTypeMusic.setAdapter(adapter);
rvTypeMusic.setLayoutManager(new GridLayoutManager(this,2));
}
public static class TypeMusicListAdapter extends
RecyclerView.Adapter<TypeMusicListViewHolder>{
private LayoutInflater inflater;
private Context context;
private List<String> data;
public TypeMusicListAdapter(Context context, List<String> data){
this.context = context;
this.inflater = LayoutInflater.from(context);
this.data = data;
}
@Override
public TypeMusicListViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = inflater.inflate(R.layout.type_music_item,parent,false);
return new TypeMusicListViewHolder(v);
}
@Override
public void onBindViewHolder(TypeMusicListViewHolder holder, int position) {
String songType = data.get(position);
//holder.musicType.setText(songType.getSongName());
holder.musicType.setText(songType);
}
@Override
public int getItemCount() {
return 0;
}
}
public static class TypeMusicListViewHolder extends RecyclerView.ViewHolder {
private TextView musicType;
public TypeMusicListViewHolder(View itemView) {
super(itemView);
musicType = (TextView) itemView.findViewById(R.id.musicType);
}
}
XML 文件
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.world.bolandian.talent.MainActivity"
tools:showIn="@layout/app_bar_main">
<android.support.v7.widget.RecyclerView
android:id="@+id/rvMusicType"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginBottom="0dp"
android:layout_marginLeft="0dp"
android:layout_marginRight="0dp"
android:layout_marginTop="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:listitem="@layout/type_music_item">
</android.support.v7.widget.RecyclerView>
</android.support.constraint.ConstraintLayout>
XML 项目
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:id="@+id/musicType"
android:padding="25dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
android:textAppearance="@style/TextAppearance.AppCompat.Display1" />
</android.support.v7.widget.CardView>
</LinearLayout>
我在这里缺少什么?我尝试了几种方法,但都没有起作用。