title: Android studio not generate signed apk
body: <p>recently I updated my working android studio IDE into Android Studio 1.5.1. but now I'm facing some trouble as after updating it did not generating signed apk file. but when I plug a device and run the app, it runs properly. when I use </p>
  
  <blockquote>
    <p>Build -> Generate Signed Apk</p>
  </blockquote>
  
  <p>in the Event Log it shows </p>
  
  <pre><code>10:38:51 AM Executing tasks: [:app:assembleRelease]
  </code></pre>
  
  <p>and the slider shows some time and it disappear. It does not show build generation completion dialog too. then I change build variant and try to run the app using a connected device. and in the Event Log it sows</p>
  
  <pre><code>10:43:32 AM Executing tasks: [:app:assembleDebug]
  </code></pre>
  
  <p>after few seconds a pop up coms saying Apk(s) generated successfully, but still the signed apk is not there at the relavent folder. and the app runs in the device properly. and my full Event Log is as follow.</p>
  
  <pre><code>10:38:51 AM Executing tasks: [:app:assembleRelease]
  10:43:32 AM Executing tasks: [:app:assembleDebug]
  10:43:46 AM Gradle build finished in 13s 964ms
  10:43:46 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:46 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:46 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:46 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:47 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:47 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:47 AM Generate Signed APK
              APK(s) generated successfully.
              Reveal in Finder
  10:43:52 AM Session 'app': Launched on samsung-sm_t211-4100cede9628b000
  </code></pre>
  
  <p>also my build.gradel file is as following.</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 22
      buildToolsVersion '23.0.0 rc3'
      defaultConfig {
          applicationId "com.lf"
          minSdkVersion 14
          targetSdkVersion 19
          versionCode 63
          versionName '2.0.9'
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
          }
      }
      productFlavors {
      }
  }
  
  dependencies {
      compile 'com.android.support:support-v4:22.2.1'
      compile project(':holoColorPickermaster')
      compile project(':qRCodeReaderViewlib')
      compile project(':volley')
      compile project(':library')
  }
  </code></pre>
  
  <p>so how can I fix this. I fully update Android studio after this was happen and it still the same. </p>