android - 使用 CardLayout 和 RecyclerView 的项目未正确显示
问题描述
我正在尝试在 Recycler 视图中列出一些卡片,但是由于某种原因,在遵循教程并提供代码之后,看起来只有一张卡片,所有内容都在一张卡片中。见图片:
initData 方法中定义的所有对象都会显示出来,但正如我所提到的,似乎所有这些对象都被添加到一张卡片上?任何帮助将不胜感激!
quiz_item_ui.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/cv">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/person_photo"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginRight="16dp"
android:layout_marginEnd="16dp"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/person_name"
android:layout_toRightOf="@+id/person_photo"
android:layout_toEndOf="@id/person_photo"
android:layout_alignParentTop="true"
android:textSize="30sp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/person_age"
android:layout_toRightOf="@+id/person_photo"
android:layout_toEndOf="@id/person_photo"
android:layout_below="@+id/person_name"/>
</RelativeLayout>
</android.support.v7.widget.CardView>
活动主页.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
android:padding="16dp"
tools:context=".HomeActivity">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/rv">
</android.support.v7.widget.RecyclerView>
</LinearLayout>
QuizItemAdapter.java
public class QuizItemAdapter extends RecyclerView.Adapter<QuizItemAdapter.QuizItemViewHolder>
{
public static class QuizItemViewHolder extends RecyclerView.ViewHolder {
CardView cv;
TextView personName;
TextView personAge;
ImageView personPhoto;
QuizItemViewHolder(View itemView)
{
super(itemView);
cv = itemView.findViewById(R.id.cv);
personName = itemView.findViewById(R.id.person_name);
personAge = itemView.findViewById(R.id.person_age);
personPhoto = itemView.findViewById(R.id.person_photo);
}
}
List<QuizItem> items;
QuizItemAdapter(List<QuizItem> items)
{
this.items = items;
}
@Override
public QuizItemViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i)
{
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.quiz_item_ui,viewGroup,false);
QuizItemViewHolder qi = new QuizItemViewHolder(v);
return qi;
}
@Override
public void onBindViewHolder(QuizItemViewHolder quizItemViewHolder, int i)
{
quizItemViewHolder.personName.setText(items.get(i).name);
quizItemViewHolder.personAge.setText(items.get(i).age);
quizItemViewHolder.personPhoto.setImageResource(items.get(i).photoId);
}
@Override
public int getItemCount()
{
return items.size();
}
}
HomeActivity.java
public class HomeActivity extends AppCompatActivity
{
private List<QuizItem> qItems;
private RecyclerView rv;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
rv = findViewById(R.id.rv);
LinearLayoutManager lm = new LinearLayoutManager(this);
rv.setLayoutManager(lm);
rv.setHasFixedSize(true);
initData();
initAdapter();
}
private void initData()
{
qItems = new ArrayList<>();
qItems.add(new QuizItem("Emma Wilson","23 years old",R.drawable.ic_location));
qItems.add(new QuizItem("Emma Wilson","23 years old",R.drawable.ic_location));
qItems.add(new QuizItem("Emma Wilson","23 years old",R.drawable.ic_location));
}
private void initAdapter()
{
QuizItemAdapter a = new QuizItemAdapter(qItems);
rv.setAdapter(a);
}
}
谢谢 !
解决方案
卡片就在那里——你可以在它们的两侧发现微小的三角形阴影。阴影需要一些空间来绘制自己。您需要从主布局中删除填充并为卡片的布局添加一些边距。
<LinearLayout 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"
android:padding="16dp" // remove this padding
tools:context=".HomeActivity">
和
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="16dp" // add margin here
android:id="@+id/cv"/>