title: AndroidStudio gradle sync : failed to resolve
body: <p>I have new clear android app. I want to add <strong>volley</strong> to my app to make HTTP request. I am developing app with Android studio using Gradle. Here is screenshot for my app:
  <a href="https://i.stack.imgur.com/ffnUv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ffnUv.png" alt="enter image description here"></a></p>
  
  <p>Ass you see i am going to add volley to my app adding this line of code <strong><em>com.mcxiaoke.volley:library-aar:1.0.0</em></strong> to build.gradle file </p>
  
  <p>I tried to add Retrofit too. But it gives same type of error: Failed to resolve: bla bla bla.</p>
  
  <p>So i think in my situation gradle can not sync any other library different than com.android......</p>
  
  <p>And i have tried add this lines of code to my build.gradle too. but nothing is changing   </p>
  
  <pre><code> buildTypes {
      release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
      }
      repositories {
          mavenCentral()
      }
  }
  </code></pre>
  
  <p>Please advise</p>
  
  <p>Edit: After comments added build.gradle files for project and for module.
  <strong>Project:</strong></p>
  
  <pre><code>buildscript {
      repositories {
          jcenter()
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:1.3.0'
      }
  }
  
  allprojects {
      repositories {
          jcenter()
      }
  }
  </code></pre>
  
  <p><strong>Module:</strong></p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 23
      buildToolsVersion "23.0.0"
  
      defaultConfig {
          applicationId "domain.testgradle"
          minSdkVersion 11
          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'])
      compile 'com.android.support:appcompat-v7:23.0.1'
      compile 'com.mcxiaoke.volley:library:1.0.19'
  }
  </code></pre>