Why does Android Studio say "Test events were not received"?

I'm trying to unit test in my android application, and this is the simple test tutorial that i'm doing.

import static org.junit.Assert.*;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.robolectric.RobolectricTestRunner;

@RunWith(RobolectricTestRunner.class)
public class ServerListManagerTest extends AndroidTestCase{

   @Test
   public void testTrueIsTrue() throws Exception {
    assertEquals(true, true);
    }
}

The directory is like this, src\main\androidTest\java\some packages\ServerListManagerTest.java

I tried changing the directory of this and also built the configuration. but Android Studio still doesn't recognize my unit test though the build was successful.

This is my build. gradle in-app,

apply plugin: 'com.android.application'

android {
   compileSdkVersion 21
   buildToolsVersion "21.1.2"

   defaultConfig {
       applicationId "com.kaist.se.pmpapp"
       minSdkVersion 16
       targetSdkVersion 21
       versionCode 1
       versionName "1.0"
   }

buildTypes {
       release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
      }
sourceSets { main { java.srcDirs = ['src/main/java', 'src/androidTest/java'] } } }



dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:22.1.1'
    androidTestCompile 'org.robolectric:robolectric:2.4'
    androidTestCompile 'junit:junit:4.12'
    androidTestCompile group: 'junit', name: 'junit', version: '4.12'
  }

What's wrong with my code????

I assume you're using Android Studio version 1.2, the latest at this time.

I don't think anything is wrong with your code. According to Jason Atwood's post, the problem seems related to gradle caching the previous results and not running it again. If you look at the "Gradle console", you'll see everything say "UP-TO-DATE". However, his suggestion of adding the "--rerun-tasks" option to the script parameters was not sufficient for me.

In addition to "--rerun-tasks", I had to turn off the in-process build and force it to call the external gradlew tool. To do this, go to...

File > Settings > Build, Execution, Deployment > Compiler

Then un-check the "Use in-process build" option. Hopefully a future release of Android Studio will fix this and we can re-enable that option.