问题
The ActionBar is visible when running the app on the device, however it is not in the preview section.
In the preview: https://i.stack.imgur.com/dNjAz.png
On the device: https://i.stack.imgur.com/IjIHn.png
This is the styles.xml
<!-- Base application theme. -->
<style name="Theme.AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
</style>
How can I make the ActionBar appear on the preview also? Thank you.
回答1:
I'm assuming you're using some sort of appcompat-v7:28.0.0-* version. I've just had the same problem. The solution for me was changing an implementation line in the build.gradle file (Module: app).
Replace this
implementation 'com.android.support:appcompat-v7:28.0.0-rc01' (or anything like this)
By this
implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'
According to this post, some appcompat-v7:28.0.0-* versions have a bug with "Design View" part of Android Studio.
回答2:
I dealt with the same problem and I think found a solution
- first open your layout editor window and click on the eye in the top left corner as shown below and then click on Show Layout Decorations
- You can change your apptheme there as well and so your toolbar, actionbar and so on...
来源：https://stackoverflow.com/questions/51089722/android-studio-actionbar-not-displayed-in-the-preview