使用 CardView 和浮动操作按钮 Android 创建布局

Question

我想使用 Material CardView 和自定义浮动操作按钮创建如下图所示的布局：

我被开发到这个 Layout xml 文件如下：

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:fab="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <RelativeLayout
        android:id="@+id/mainview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <android.support.v7.widget.CardView
            android:id="@+id/cv"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:cardCornerRadius="2dp"
            app:cardElevation="2dp"
            android:layout_marginBottom="@dimen/cardMarginVertical"
            android:layout_marginLeft="@dimen/cardMarginHorizontal"
            android:layout_marginRight="@dimen/cardMarginHorizontal"
            android:layout_marginTop="@dimen/cardMarginVertical"
            app:cardPreventCornerOverlap="false"
            app:contentPadding="0dp">

            <com.github.florent37.materialviewpager.sample.ExpandableTextView
                android:id="@+id/expandingTextView"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:textSize="15dp"
                android:layout_marginLeft="10dp"
                android:layout_marginTop="10dp"
                android:layout_marginRight="10dp"
                android:layout_marginBottom="10dp"
                android:text="@string/longText" />

            <RelativeLayout
                android:id="@+id/buttonlayout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_below="@+id/expandingTextView"
                android:layout_gravity="bottom"
                android:background="@android:color/transparent">

                <com.getbase.floatingactionbutton.FloatingActionButton
                    android:id="@+id/action_c"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    fab:fab_colorNormal="#fff"
                    android:layout_alignParentRight="true"
                    fab:fab_colorPressed="#fff"
                    android:visibility="visible" />
            </RelativeLayout>
        </android.support.v7.widget.CardView>
    </RelativeLayout>
</FrameLayout>

Answer 1

要实现像您的图片一样的 UI，下面的一些代码会有所帮助。

FloatingActionButton 中的参数layout_anchor 和layout_anchorGravity 是重点。

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <android.support.v7.widget.CardView
            android:id="@+id/cv"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="16dp">

                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:text="The Android Support Library package is a set of code libraries that provide backward-compatible versions of Android framework APIs as well as features that are only available through the library APIs. Each Support Library is backward-compatible to a specific Android API level. This design means that your applications can use the libraries' features and still be compatible with devices running Android 1.6 (API level 4) and up." />

        </android.support.v7.widget.CardView>

    </android.support.v4.widget.NestedScrollView>

    <android.support.design.widget.FloatingActionButton
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        app:layout_anchor="@id/cv"
        app:layout_anchorGravity="right|end|bottom"
        android:layout_margin="16dp"
        android:clickable="true"/>

</android.support.design.widget.CoordinatorLayout>

编辑：

早期答案在 Android 5.0.1 和 5.0.2 中存在一些错误，FAB 将显示在 CardView 下方。

在CardView 之外添加NestedScrollView 和layout_behavior 以在Android 5.0.1 和5.0.2 中工作