Dart SDK is not configured : <p>I installed Flutter and set up Android Studio. Then I cloned an example of flutter on GitHub (<a href="https://github.com/flutter/flutter" rel="noreferrer">https://github.com/flutter/flutter</a>) and launched it in Android Studio, but it warns me "Dart SDK is not configured", this happened to my co-worker as well. But if I create a new project in Android Studio, no problem at all.</p>

<p>What I have done:</p>

<ol>
<li><p>Installed Flutter</p></li>
<li><p>Installed Android Studio, along with Flutter plugin including Dart plugin</p></li>
<li><p>Flutter run in command line works fine, all five tests passed. (See below)</p></li>
</ol>

<blockquote>
  <p>[✓] Flutter (on Mac OS X 10.13.3 17D47, locale en-US, channel dev)
      • Flutter version 0.0.22 at /Users/katelyn/flutter
      • Framework revision 3001b3307d (7 days ago), 2018-01-30 11:37:15 -0800
      • Engine revision 8f2d72b183
      • Tools Dart version 2.0.0-dev.16.0
      • Engine Dart version 2.0.0-edge.7af4db0ea091dddca6b2da851e6dda8d7f9467e8</p>
  
  <p>[✓] Android toolchain - develop for Android devices (Android SDK 27.0.3)
      • Android SDK at /Users/katelyn/Library/Android/sdk
      • Android NDK location not configured (optional; useful for native profiling support)
      • Platform android-27, build-tools 27.0.3
      • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
      • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)</p>
  
  <p>[✓] iOS toolchain - develop for iOS devices (Xcode 9.2)
      • Xcode at /Applications/Xcode.app/Contents/Developer
      • Xcode 9.2, Build version 9C40b
      • ios-deploy 1.9.2
      • CocoaPods version 1.4.0</p>
  
  <p>[✓] Android Studio (version 3.0)
      • Android Studio at /Applications/Android Studio.app/Contents
      • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)</p>
  
  <p>[✓] Connected devices
      • Android SDK built for x86 • emulator-5554 • android-x86 • Android 7.1.1 (API 25) (emulator)</p>
</blockquote>

<p>Last week, I can run their example thru command line (in that dir),</p>

<pre><code>flutter run 
</code></pre>

<p>but now I it shows some errors with Gradle. </p>

<blockquote>
  <p>Launching lib/main.dart on Android SDK built for x86 in debug mode...
  Initializing gradle...                                0.7s
  Resolving dependencies...<br>
  * Error running Gradle:
  Exit code 1 from: /Users/katelyn/AndroidStudioProjects/flutter/examples/flutter_gallery/android/gradlew app:properties:</p>
  
  <p>FAILURE: Build failed with an exception.</p>
  
  <ul>
  <li><p>Where:
  Build file '/Users/katelyn/AndroidStudioProjects/flutter/examples/flutter_gallery/android/app/build.gradle' line: 20</p></li>
  <li><p>What went wrong:
  A problem occurred evaluating project ':app'.
  3</p></li>
  <li><p>Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.</p></li>
  <li><p>Get more help at <a href="https://help.gradle.org" rel="noreferrer">https://help.gradle.org</a></p></li>
  </ul>
  
  <p>BUILD FAILED in 0s</p>
  
  <p>Please review your Gradle project setup in the android/ folder.</p>
</blockquote>

<p>Sorry in advance I don't have enough reputation to upload pics.</p>
