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Android Build a Simple Android App with Java Creating the Screen Layout Editing a Layout File

Ruslan T
Ruslan T
1,706 Points
Posted by Ruslan T
Ruslan T
1,706 Points

Failed to load AppCompat ActionBar with unknown error.

I'm trying to open the design tab, but it shows nothing, there is no "Hello World!" message anywhere, and it's just an empty screen.

It also shows this error:

Failed to load AppCompat ActionBar with unknown error.

here is my xml when I created the file.

<?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"
    tools:context=".FunActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

can anyone help?

Steve Mbouadeu
Steve Mbouadeu
Courses Plus Student 358 Points

I got the same error!

1 Answer

Steve Mbouadeu
Steve Mbouadeu
Courses Plus Student 358 Points

This worked for me. Modify /res/values/styles.xml from:

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"> </style> to:

<style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar"> </style>

Anuj Bhusari
Anuj Bhusari
12,240 Points
Anuj Bhusari
Anuj Bhusari
12,240 Points

Do you know why does this work?