在ScrollView中时，Cardview阴影看起来有所不同

Question

I stumbled upon something weird. I am using the same CardView component in more than one place in my app, all with the same elevation (3dp), and they all looks the same. However, for one scenario I need to embed the CardView inside a ScrollView . I didn't change anything in the CardView configuration, but the shadow now looks different.

This is my layout:

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:app="http://schemas.android.com/apk/res-auto"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:clipChildren="false"
            android:clipToPadding="false"
            android:padding="16dp"
            android:scrollbars="none">

    <androidx.cardview.widget.CardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:clipChildren="false"
        android:clipToPadding="false"
        app:cardCornerRadius="8dp"
        app:cardElevation="3dp"
        app:cardUseCompatPadding="true">

        <!-- some other views-->

     </androidx.cardview.widget.CardView>
</ScrollView>

In the picture below you can see on the right the CardView and on the left the two shadows: on the top the shadow generated by the CardView alone, on the bottom the one generated when the CardView is inside a ScrollView . As you can see the second one appears darker and thicker.

NOTE: The background color (#FAFAFA) is the same in both scenario.

Answer 1

For both cases, I would check the following properties as it could contribute to the difference you're seeing:

• getTranslationZ()
• getElevation()
• getOutlineAmbientShadowColor() (this is only valid in API 28+)
• getOutlineSpotShadowColor() (this is only valid in API 28+)

Plus, checking Layout inspector to see if there's any view that could affect to the rendering.

Also, this article from Sebastiano Poggi could be of help.