java - Android InflateException FloatingActionButton

Question

我有 recyclerview 项目，我正在尝试编辑它们的外观。我尝试向 recyclerview 的每个项目添加一个 float 操作按钮，但它引发了此错误:

android.view.InflateException: Binary XML file line #0: Error inflating class <unknown>

每个 RecyclerView 项目的设计如下:

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/constraintLayout"
    android:layout_width="match_parent"
    android:layout_height="@dimen/list_item_height"
    android:layout_marginLeft="@dimen/margin_medium"
    android:layout_marginRight="@dimen/margin_medium"
    android:gravity="center_vertical">

    <ImageView
        android:id="@+id/shoeImage"
        android:adjustViewBounds="true"
        android:scaleType="centerCrop"
        android:layout_width="64dp"
        android:layout_height="match_parent"
        app:srcCompat="@drawable/air" />

    <TextView
        android:id="@+id/textBrandName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="16dp"
        android:text="..."
        android:textColor="@color/common_google_signin_btn_text_dark_focused"
        app:layout_constraintHorizontal_bias="0.504"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/textShoeName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:text="..."
        android:textColor="@color/common_google_signin_btn_text_dark_focused"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintHorizontal_bias="0.504"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.698" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/floatingActionButton2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="top|bottom|end"
        android:layout_marginStart="8dp"
        android:clickable="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toEndOf="@+id/textBrandName"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

注意...在添加 FloatingActionButton 代码之前一切正常。可能是什么问题呢？ FAB 按钮没有图像，因此无法加载任何太大的可绘制对象。谢谢!

Answer 1

将其编译到您的 build.gradle 文件中:

compile 'com.android.support:design:23.3.0'
compile 'com.android.support.constraint:constraint-layout:1.0.2'