[android] Syncing Android Studio project with Gradle files

Old Answer

When trying to run the application, instead of selecting the directory highlighted here in blueenter image description here

I selected the subdirectory instead

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and clicked "run".All the issues with Gradle are automatically resolved and the missing apk directory is automatically created.

New Solution

The Sync project with gradle files button disappeared from Android Studio for a while.Its back and you can find it here:

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hit the button and wait for the task to complete