title: Android Studio: No build variant found error
body: <p>i am new to android development, i started developing from scratch on a project i bought online, following the documentation, i encountered a error saying <strong>No variants found for 'app'. Check build files to ensure at least one variant exists.</strong></p>
  <p>Here is the build.gradle code</p>
  <pre><code>apply plugin: 'com.android.application'
  
  android {
  compileSdkVersion 29
  buildToolsVersion &quot;29.0.1&quot;
  defaultConfig {
      applicationId &quot;com.app-10.app&quot;
      minSdkVersion 23
      targetSdkVersion 29
      versionCode 1
      versionName &quot;1.0&quot;
      testInstrumentationRunner &quot;androidx.test.runner.AndroidJUnitRunner&quot;
  }
  buildTypes {
      release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
      }
  }
  }
  
  dependencies {
  implementation fileTree(include: ['*.jar'], dir: 'libs')
  implementation 'androidx.appcompat:appcompat:1.0.2'
  implementation 'com.google.android.material:material:1.0.0'
  implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
  implementation 'androidx.vectordrawable:vectordrawable:1.0.1'
  implementation 'androidx.legacy:legacy-support-v4:1.0.0'
  testImplementation 'junit:junit:4.12'
  androidTestImplementation 'androidx.test:runner:1.2.0'
  androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
  // Third Party Libraries
  //Glide library for image fetching from the web
  implementation 'com.github.bumptech.glide:glide:4.9.0'
  annotationProcessor 'com.github.bumptech.glide:compiler:4.9.0'
  //Material library for styling blocks
  implementation 'com.google.android.material:material:1.0.0'
  // Google Gson
  implementation 'com.google.code.gson:gson:2.8.5'
  // Retrofit
  implementation 'com.squareup.retrofit2:retrofit:2.6.1'
  implementation 'com.squareup.retrofit2:converter-gson:2.6.1'
  // Android-SpinKit
  implementation 'com.github.ybq:Android-SpinKit:1.4.0'
  
  implementation files('libs/YouTubeAndroidPlayerApi.jar')
  
  // gotev/android-upload-service
  implementation &quot;net.gotev:uploadservice:3.5.2&quot;
  
  //A fast circular ImageView perfect for profile images
  implementation 'de.hdodenhof:circleimageview:3.0.1'
  
  implementation 'org.apache.commons:commons-io:1.3.2'
  
  }
  </code></pre>