title: Android Studio Gradle project sync complete with errors
body: <p>I recently decided to learn Android programming, so I installed Android Studio and Android SDK on my Ubuntu machine. The issue is when I build a new project, it says : </p>
  
  <pre><code>Gradle Sync completed with some erros
  </code></pre>
  
  <p>and the log is :</p>
  
  <pre><code>/home/moein/apps/android-studio-projects/Testapp/app/build.gradle
      Error:Error:line (24)Failed to resolve: com.android.support:appcompat-v7:23.+
      Error:Error:line (23)Failed to resolve: junit:junit:4.12
  </code></pre>
  
  <p>my build.gradle:</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 23
      buildToolsVersion "23.0.2"
  
      defaultConfig {
          applicationId "com.example.moein.testapp"
          minSdkVersion 23
          targetSdkVersion 23
          versionCode 1
          versionName "1.0"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      testCompile 'junit:junit:4.12'
      compile 'com.android.support:appcompat-v7:23.0.0'
  }
  </code></pre>