title: Cannot resolve symbol v7 : import android.support.v7.widget.RecyclerView
body: <p>I'm trying to import this :
  <code>import android.support.v7.widget.RecyclerView;</code></p>
  
  <p>But I got that : "Cannot resolve symbole v7".</p>
  
  <p>Indeed, when I'm typing <code>android.support.</code> I can choose v4 but not v7</p>
  
  <p>This is my build.gradle : </p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 28
      defaultConfig {
          applicationId "com.example.bibstandardandroidstudio"
          minSdkVersion 23
          targetSdkVersion 28
          versionCode 1
          versionName "1.0"
          testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
          }
      }
      compileOptions {
          sourceCompatibility JavaVersion.VERSION_1_8
          targetCompatibility JavaVersion.VERSION_1_8
      }
      buildToolsVersion '28.0.3'
  }
  
  dependencies {
      implementation fileTree(include: ['*.jar'], dir: 'libs')
      implementation 'androidx.appcompat:appcompat:1.1.0-alpha04'
      implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
      testImplementation 'junit:junit:4.12'
      androidTestImplementation 'androidx.test:runner:1.2.0-alpha03'
      androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0-alpha03'
      implementation 'com.google.android.material:material:1.0.0'
      implementation 'org.mindrot:jbcrypt:0.4'
      implementation 'com.android.volley:volley:1.1.1'
      implementation 'com.google.code.gson:gson:2.8.5'
      implementation 'com.android.support:appcompat-v7:28.0.0'
      implementation 'com.android.support:recyclerview-v7:28.0.0'
  }
  </code></pre>
  
  <p>I'm new to Android and I'm trying to follow this tutorial : <a href="https://developer.android.com/guide/topics/ui/layout/recyclerview" rel="noreferrer">Create a List with RecyclerView </a></p>
  
  <p>I saw that <code>implementation 'com.android.support:appcompat-v7:28.0.0'</code> should unlock my situation but it don't seem to work </p>