相关疑难解决方法(0)

我有一个ListView,每个列表项我希望它在它下面显示一个阴影.我正在使用Android Lollipop的新高程功能在View上设置一个我想要投射阴影的Z,并且我已经使用ActionBar(技术上是Lollipop中的工具栏)有效地做到了这一点.我正在使用Lollipop的高程,但由于某种原因,它没有在列表项下显示阴影.以下是每个列表项的布局设置方式:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    style="@style/block"
    android:gravity="center"
    android:layout_gravity="center"
    android:background="@color/lightgray"
    >

    <RelativeLayout
        android:layout_width="300dp"
        android:layout_height="300dp"
        android:layout_marginLeft="40dp"
        android:layout_marginRight="40dp"
        android:layout_marginTop="20dp"
        android:layout_marginBottom="20dp"
        android:elevation="30dp"
        >

        <ImageView
            android:id="@+id/documentImageView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="centerCrop" />

        <LinearLayout
            android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@color/alphared"
            android:layout_alignParentBottom="true" >

            <appuccino.simplyscan.Extra.CustomTextView
                android:id="@+id/documentName"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:textColor="@color/white"
                app:typeface="light"
                android:paddingLeft="16dp"
                android:paddingTop="8dp"
                android:paddingBottom="4dp"
                android:singleLine="true"
                android:text="New Document"
                android:textSize="27sp"/>

            <appuccino.simplyscan.Extra.CustomTextView
                android:id="@+id/documentPageCount"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:textColor="@color/white"
                app:typeface="italic"
                android:paddingLeft="16dp"
                android:layout_marginBottom="16dp"
                android:text="1 page"
                android:textSize="20sp"/>

        </LinearLayout>

    </RelativeLayout>

</RelativeLayout>

但是,这是它如何显示列表项,没有阴影:

我也试过以下无济于事:

1. 将高程设置为ImageView和TextViews本身而不是父布局.
2. 将背景应用于ImageView.
3. 用TranslationZ代替Elevation.

在SDK Manager的Android 5.0示例中,有ElevationBasic示例.它显示了两个View对象:圆形和方形.圆圈android:elevation设置为30dp:

<?xml version="1.0" encoding="utf-8"?>
<!--
 Copyright 2014 The Android Open Source Project

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF …

我需要向具有“来自 zeplin”这些属性的按钮添加阴影：

这就是设计

我试过这段代码

<Button
        android:id="@+id/btn_sign_in"
        android:layout_width="match_parent"
        android:layout_height="48dp"
        android:layout_marginTop="35dp"
        android:background="@drawable/auth_button_shape"
        android:shadowColor="#41ff4800"
        android:shadowDx="0"
        android:shadowDy="8"
        android:text="@string/sign_in"
        android:textAllCaps="true"
        android:textColor="@android:color/white"
        android:textSize="14sp" />

auth_button_shape

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#ff7c44" />
<corners android:radius="100dp" />
</shape>

但不起作用，其他属性“模糊”和“传播”我如何为按钮设置它们。

谢谢。