Why Active Android is not working with gradle 2.0?

Question

I am using Active Android in my app. It was working fine till I upgraded my Android Studio to 2.0 from 1.3. With this upgrade my gradle also got upgraded to 2.0 which is causing some issue with the Active Android.

I am getting this error when building with gradle 2.0.

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.activeandroid.TableInfo.getTableName()' on a null object reference
                                                                       at com.activeandroid.Cache.getTableName(Cache.java:156)
                                                                       at com.activeandroid.query.From.addFrom(From.java:169)
                                                                       at com.activeandroid.query.From.toSql(From.java:250)
                                                                       at com.activeandroid.query.From.execute(From.java:298)

I tried building my old studio with gradle 1.3 it is still working fine. Any help please?

build.gradle file when app is giving the above error

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.0.0'
        classpath 'com.google.gms:google-services:2.0.0-beta2'
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

build.gradle when app is working fine

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.3.0'
        classpath 'com.google.gms:google-services:2.0.0-beta2'
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

gradle wrapper properties

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-2.10-all.zip

Answer 1

I ran into this problem too, I found it's only an issue on Android 23+ devices, and it can be avoided if you turn Instant Run off (File->Settings->Build, Execution, Deployment->Instant Run).

If you want to keep Instant Run you can try UnChecking "Restart Activity on Code Changes"

On Mac:

Preferences > Build, Execution, Deployment > Instant Run > Uncheck "Restart Activity on Code Changes"

Answer 2

There is a problem with ActiveAndroid which is not being able to retrieve the Model classes searching in the DexFile when Instant run is activated Some info about DexFile and Instant run here

There are three possible workarounds:

1. Disable Intant run Android Studio -> Preferences -> Intant run
2. Add the already suggested code in AndroidManifest:

<meta-data
    android:name="AA_MODELS"
    android:value="com.myapp.model.Item, com.myapp.model.Category" />

3. Add the following code in the ActiveAndroid intialization:

Configuration.Builder config = new Configuration.Builder(this);
config.addModelClasses(Model1.class, Model2.class);
ActiveAndroid.initialize(config.create());

Hope it helps