Question

我正在使用回收站视图，但它没有显示任何内容。

mycode的

Recycler view：

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

MainActivity：

 recyclerView=(RecyclerView)findViewById(R.id.rv);
    RecyclerViewLayoutManager=new LinearLayoutManager(getApplicationContext());
    recyclerView.setLayoutManager(RecyclerViewLayoutManager);
    RecyclerView.Adapter adapter=new RecyclerViewAdapter(data,dataname,dataid,datamyname);

    recyclerView.setAdapter(adapter);

Recyclerview适配器：

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


ArrayList<String> data;
ArrayList<String>dataname;
ArrayList<String>dataid;
ArrayList<String>datamyname;

View view1;
String tempname;


public RecyclerViewAdapter(ArrayList<String> data1,ArrayList<String> data2,ArrayList<String>data3,ArrayList<String>data4) {
    this.data = data1;
    this.dataname = data2;
    this.dataid = data3;
    this.datamyname = data4;
}

    @Override
public RecyclerViewAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        view1= LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview,parent,false);
        return new ViewHolder(view1);

}

@Override
public void onBindViewHolder(RecyclerViewAdapter.ViewHolder holder, int position) {
    holder.tv1.setText(data.get(position));
    holder.tv2.setText(dataname.get(position));
    tempname=dataid.get(position);
    //imag=(ImageView)holder.findViewById(R.id.imageView2);

}

@Override
public int getItemCount() {
    return 0;
}

public class ViewHolder extends RecyclerView.ViewHolder{
    TextView tv1,tv2,copy,share;
    ImageView imag;
    public ViewHolder(View itemView) {
        super(itemView);
         tv1=(TextView)itemView.findViewById(R.id.eventtitle);
        tv2=(TextView)itemView.findViewById(R.id.textView5);
        imag=(ImageView)itemView.findViewById(R.id.imageView2);
        Glide.with(MyApp.getContext()).load(tempname).into(imag);
    }
}
}

 <android.support.v7.widget.CardView
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="450dp"
    xmlns:tools="http://schemas.android.com/tools"
    android:paddingLeft="8dp"
    android:paddingRight="8dp"
    android:paddingBottom="4dp"
    android:paddingTop="4dp"
    card_view:contentPadding="4dp"
    card_view:cardElevation="4dp"
    android:id="@+id/card"
    card_view:cardCornerRadius="20dp"
    tools:context=".BloodDonationHealth">
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="400dp"
        android:id="@+id/rl">


        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:text="Title"
            android:id="@+id/eventtitle"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:text="Description  W/khrn_client t.GattService: clientConnect() - tion of void com.yolo.music.YoloInitManager.onApplicationCreate(android.app.Application) took 274.353ms 11-01 11:41:43.087 507-1096/system_process W/art: Long monitor contention event with owner maddress=08:7C:BE:52:00:56, isDirect=false t.GattService: clientConnect() - address=08:7C:BE:52:00:56, isDirect=false init_window window 0x484b3038, 480x800 hintTransform 0x0 do_pre 1 10-31 20:21:04.481 1777-1790/bootcamplearning.humanplanet I/art: Background sticky concurrent mark sweep GC freed 40216(2MB) AllocSpace objects, 2(32KB) LOS objects, 4% free, 26MB/27MB, paused 5."
            android:id="@+id/textView5"
            android:layout_gravity="left|center_vertical"
            android:layout_below="@+id/imageView2"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true" />
        <ImageView
            android:layout_width="match_parent"
            android:layout_height="120dp"
            android:id="@+id/imageView2"
            android:src="@drawable/globe"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_marginTop="36dp" />

    </RelativeLayout>




<LinearLayout
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_centerVertical="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true"
    android:layout_gravity="bottom">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView3"
        android:src="@drawable/location" />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView4"
        android:src="@drawable/user"/>

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/share"
        android:id="@+id/imageView5" />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView6"
        android:src="@drawable/chat"/>
</LinearLayout>
</android.support.v7.widget.CardView>

</RelativeLayout>

这是我的代码，我无法配置什么是错误的，有人可以帮我解决这个问题吗？我在哪里做错了，你能告诉我吗

Answer 1

RecyclerView没有显示任何内容

@Override
public int getItemCount() {
    return 0;
}

因为您告诉app该列表没有要显示的任何项目。

试试这个

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

Answer 2

修改此方法：

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

它应该返回列表中的项目数。

Answer 3

getItemCount应该返回数据的计数。

Recycler视图在布局中没有显示任何内容

3 个答案: