i deleted folders "platforms" and "build-tools" from SDK folder.
You should not delete the folders manually, but you use
Android SDK Manager instead. Now, you should run your Android SDK Manager and reinstall them.
I use this combination below, and it works on my Linux machine LAMW 0.8 to build Android app to run on my Android 7 mobile phone:
- Android SDK Tools Rev. 25.2.5
- Android SDK Platform-tools Rev. 28.0.1
- Android SDK Build-tools Rev. 25
- SDK Platform API 25 Rev. 3
- Google APIs ARM EABI v7a System Image API 25 Rev. 14