.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity

问题

<!-- Base application theme. -->
<style name="AppTheme" parent="android:Theme.Material.Light.NoActionBar">
    <!-- Customize your theme here. -->
    <item name="colorPrimary">@color/ColorPrimary</item>
    <item name="colorPrimaryDark">@color/ColorPrimaryDark</item>
</style>

This is my code Showing error like this java.lang.RuntimeException: Unable to start activity ComponentInfo{com.colors.floatingactionbutton/com.colors.floatingactionbutton.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.

回答1:

You need to use one theme of the AppCompact library like @style/Theme.AppCompat.Light instead of android:Theme.Material.Light.NoActionBar

回答2:

In your Android Studio, click on the "theme button" and select the appCompat theme in the dialog.

来源：https://stackoverflow.com/questions/32376815/illegalstateexception-you-need-to-use-a-theme-appcompat-theme-or-descendant