我们在布局文件里定义RecyclerView时,可以使用tools属性预览数据,如下:
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:itemCount="10"
tools:layoutManager="LinearLayoutManager"
tools:listitem="@layout/item_person_info"
tools:orientation="vertical" />
item_person_info文件定义如下:
<?xml version="1.0" encoding="utf-8"?>
<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="50dp"> <TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
tools:text="@tools:sample/full_names" /> <ImageView
android:layout_width="40dp"
android:layout_height="40dp"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
tools:src="@tools:sample/avatars" />
</android.support.constraint.ConstraintLayout>
预览效果如下:
将tools:layoutManager的值改为GridLayoutManager,预览效果如下: