Android Studio 3.4.1 constraintlayout editor preview not working AGAIN

Question

I believe I have had similar issues in the past ever since v3.x and they keep coming. I don't know how many hours I have to spend on trying to use the layout editor and they just can't get it right.

Anyway, here is the xml code:

<?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:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
    android:id="@+id/textView"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:text="TextView"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

Here is how it looks:

Any item I drag in gets put in the top left corner with 0 size. No matter if you set exact sizes or just constraints.

My Android Studio version is 3.4.1
Using 28.0.0 support libs.
I cannot downgrade due to company policy, so that's not an option.

Constraint Layout version is the latest:

implementation 'com.android.support.constraint:constraint-layout:2.0.0-beta1'

It did not work with earlier versions either.

I have tried several things which "worked" earlier with other similar bugs:

• Using different themes
• Trying different API versions in the layout editor
• Invalidate cache/restart
• Updated Android Studio (to this version)

Any suggestion is welcome

Answer 1

Just cleaning the project worked for me.

Answer 2

So basically the issue was completely elsewhere in another layout file, nothing to do with constraint layout. Anyway after a clean and build AND restart it eventually worked!