android：如何在EditText视图上显示阴影？

Question

I apply elevation attribute and a drawable background which supply a rounded outline to the EditText View , but there is no shadow as expected.

<?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="match_parent"
    android:layout_margin="20dp"
    android:background="#FAFAFA"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/editText"
        android:layout_width="0dp"
        android:layout_height="51dp"
        android:layout_marginTop="52dp"
        android:elevation="20dp"
        android:background="@drawable/rounded_edittext"
        android:drawableStart="@drawable/ic_search_icon"
        android:drawableLeft="@drawable/ic_search_icon"
        android:ems="10"
        android:inputType="textPersonName"
        android:paddingLeft="20dp"
        android:paddingRight="20dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView" />
</android.support.constraint.ConstraintLayout>

And the background rounded_edittext.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#FFFFFF"/>
    <corners
        android:bottomRightRadius="27.5dp"
        android:bottomLeftRadius="27.5dp"
        android:topLeftRadius="27.5dp"
        android:topRightRadius="27.5dp"/>
    <stroke android:color="#66000000" android:width="0.5dp"/>
</shape>

UPDATE

Below is the original design.

border color #000000 opacity 10(0~100) shadow color #000000 opacity 5(0~100)

Answer 1

Replace your rounded_edittext.xml with the following code:

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item >
    <shape
        android:shape="rectangle">
        <solid android:color="@android:color/darker_gray" />
        <corners android:radius="27.5dp"/>
    </shape>
</item>
<item android:right="1dp" android:left="1dp" android:bottom="2dp">
    <shape
        android:shape="rectangle">
        <solid android:color="#FFFFFF"/>
        <corners
            android:radius="27.5dp"/>
        <stroke android:color="#66000000" android:width="0.5dp"/>
    </shape>
</item>

Also, replace android:elevation="20dp" from EditText with android:elevation="4dp"

Answer 2

Go here : Android View shadow

Or if you want to a put shadow under your view, add the following

In your Layout.xml

<View android:layout_width="match_parent"
    android:layout_height="5dp"
    android:background="@drawable/dropshadow"/>

drawble/dropshadow.xml >

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <gradient android:startColor="@android:color/transparent"
        android:endColor="#88333333"
        android:angle="90"/>
</shape>