material design - Android Theme - "Cannot resolve symbol" error on statusBarColor item

Question

In my Android (API 30) app theme (file themes.xml) using MaterialComponents the "android:statusBarColor" works but displays the following error in red :Cannot resolve symbol 'android:statusBarColor'

You can reproduce this by creating a new android projet with the "Tabbed Activity" template :

<resources xmlns:tools="http://schemas.android.com/tools">
    <!-- Base application theme. -->
    <style name="Theme.AppTest" parent="Theme.MaterialComponents.DayNight.DarkActionBar">
        <!-- Primary brand color. -->
        <item name="colorPrimary">@color/purple_500</item>
        <item name="colorPrimaryVariant">@color/purple_700</item>
        <item name="colorOnPrimary">@color/white</item>
        <!-- Secondary brand color. -->
        <item name="colorSecondary">@color/teal_200</item>
        <item name="colorSecondaryVariant">@color/teal_700</item>
        <item name="colorOnSecondary">@color/black</item>
        <!-- Status bar color.  IN RED - "Cannot resolve symbol" below  -->
        <item name="android:statusBarColor" tools:targetApi="l">?attr/colorPrimaryVariant</item>  
        <!-- Customize your theme here. -->
    </style>

In fact, all android items in themes produce this Cannot resolve symbol, like :

<style name="ToolbarPopupTheme" parent="ThemeOverlay.MaterialComponents">
    <!--   android:background below in RED-->
    <item name="android:background">?attr/colorPrimary</item>
</style>

If any of you have any insight on this, it would be great.

question from:https://stackoverflow.com/questions/65858339/android-theme-cannot-resolve-symbol-error-on-statusbarcolor-item

Answer 1

android:statusBarColor is introduced in API level 21. So, If You are trying to use this property in default styles.xlm. You will get Cannot resolve symbol.

You can create styles.xml in values-v21 folder and there you can use this attribute without any error