Android Studio layout Error: Unknown attribute

Question

Android Studio Code Completion does not seem to work on xml, nor does it recognize the xml attribute except attrs on Android support v7 views. Screenshot:

my views, which appear on android.support.design.v7, display correctly:

Answer 1

If you are Android Studio, then go to the tools, then Android, and then click "Create" using gradle, it will solve the error. I also came across this.

Tools-> Android-> Build with Gradle

Answer 2

I had this problem for a while, and I tried all the "provided solutions";

• Sync Gradle Files.
• Invalid cache.
• Deleted and re-added project.
• Reinstall Android Studio.

Nothing helped until I came across this answer (4gus71n), which worked for me every time this rather rare but annoying question presented itself: fooobar.com/questions/2039152 / ...

In my case, I;

1. Closed Android Studio.
2. Cleared the contents of C:\Users\MyUsername\.AndroidStudio3.2\system\caches\ .
3. Restarted Android Studio.

The treat worked!