title: Unable to locate android SDK for flutter doctor
body: <p>I have tried uninstalling and reinstalling flutter on my computer twice but whenever I run <code>flutter doctor</code> in the terminal I am still met with the following error.</p>
  <pre><code>[✗] Android toolchain - develop for Android devices
  ✗ Unable to locate Android SDK.
    Install Android Studio from:
    https://developer.android.com/studio/index.html
    On first launch it will assist you in installing the Android SDK
    components.
    (or visit https://flutter.dev/docs/get-started/install/macos#android-setup
    for detailed instructions).
    If the Android SDK has been installed to a custom location, set
    ANDROID_SDK_ROOT to that location.
    You may also want to add it to your PATH environment variable.
  </code></pre>
  <p>Does anyone know how to fix this problem? Also, could this be the reason that none of my emulators are running my app? Thanks, and sorry, I am still new to Flutter and android studio.</p>