Develop Reference

Found more than one jar in the 'lintChecks' configuration

I want to add custom lint rules to my projects, but I get error while syncing project.
Execution failed for task ':app:prepareLintJar'.
Found more than one jar in the 'lintChecks' configuration. Only one file is supported. If using a separate Gradle project, make sure compilation dependencies are using compileOnly
How can I check which library or module is adding another jar?

I fixed problem. My dependencies in my custom rules module was
dependencies {
api "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
compileOnly 'com.android.tools.lint:lint-api:26.5.3'
compileOnly 'com.android.tools.lint:lint-checks:26.5.3'
}
I changed kotlin dependency to compileOnly and it worked
dependencies {
compileOnly "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
compileOnly 'com.android.tools.lint:lint-api:26.5.3'
compileOnly 'com.android.tools.lint:lint-checks:26.5.3'
}

Migrating to Gradle 3.0.0: Error - D8: Program type already present

I am migrating my Android project to Gradle 4.4 and Android Gradle plugin 3.1.2.
It has a library module which depends on parceler library and defines its dependency as follows:
build.gradle of library module:
...
// parceler for serialization (https://github.com/johncarl81/parceler)
implementation "org.parceler:parceler-api:1.0.4"
annotationProcessor "org.parceler:parceler:1.0.4"
...
This seems to compile well and generates my aar file.
Further, my main app module also has a direct dependency on parceler module and contains above lines as dependencies in its build.gradle, along with above aar file.
build.gradle of main app module:
...
api(group: 'com.example.mylibrary', name: 'mylibrary', version: "1.0.7", ext: 'aar') {
transitive = true;
changing = true
}
// parceler for serialization (https://github.com/johncarl81/parceler)
implementation "org.parceler:parceler-api:1.0.4"
annotationProcessor "org.parceler:parceler:1.0.4"
...
Everything works until I try to generate my APK, which fails with the following error.
D8: Program type already present: org.parceler.Parceler$$Parcels$1
Task :MPCApp:transformDexArchiveWithDexMergerForRelease FAILED
When I expand my library project in Android studio, I see Parcels.class under org.parceler package. But it seems similar file is also generated by main app module under the same package which is causing the clash.

Upgrade to the latest (currently 1.1.10) - We got rid of the Parcels generated class.

Android .aar dependencies aren’t resolving in app project that depends on .aar

i have created an android library AAR in android studio 2.1.3 in which i use the following dependencies:
compile 'com.google.android.gms:play-services-vision:9.4.0+'
compile 'com.google.android.gms:play-services-wearable:9.4.0+'
compile 'pl.droidsonroids.gif:android-gif-drawable:1.2.3'
now i am using this aar in an application but those dependencies were failing unless i add them to the dependencies of the new app.
i search here and i found that i need to add the following line:
compile (project(':LIBNAME-release')) {transitive = true}
but this didn't work. is there something i missed? or is it related to the obfuscation i did to the aar file? or is it a must to add these dependencies to the app?

Try to compile you project first:
dependencies {
compile project(':Name-Of-Your-Project')
}
This is Ashton Engberg's suggestion from that post

what is the difference between compile, testCompile and provided in gradle dependency

I am using android studio and in project structure -> dependencies tab following options i can see:
Compile
Provided
APK
Test Compile
Debug Compile
Release Compile
my question: what is the difference between compile, testCompile and provided in gradle dependency

compile is the group of dependencies you need to build your application while testCompile is a group of dependencies that you need only for testing.
Look for instance at this build.gradle (taken from here)
apply plugin: 'java'
repositories {
mavenCentral()
}
dependencies {
compile group: 'org.hibernate', name: 'hibernate-core', version: '3.6.7.Final'
testCompile group: 'junit', name: 'junit', version: '4.+'
}
This specifies that hibernate-core is needed to build your code but junit (a testing framework) is needed just for testing. Since it's not needed at runtime, it's not going to be included in the released package.

You should read the User Guide that comes with the distribution, or read it online at http://gradle.org/documentation/ .
In short, "compile" is for dependencies for your "main" code, "testCompile" for your test classes, and "provided" is used for dependencies that are used at compile time, but not stored in your WAR file (because they're expected to be available in your web container).
The following posting might have relevant information: Compile, Provided, APK - Android dependency scope .

Dagger not generating components for /test class

I am following the guide here: https://github.com/ecgreb/dagger-2-testing-demo
I have the following setup in my app/src/main (the injection and #Provides code omitted):
public class FlingyApplication extends Application {
#Singleton
#Component(modules = { FlingyModule.class })
public interface FlingyComponent
}
#Module
public class FlingyModule
In app/src/test:
public class TestFlingyApplication extends Application {
#Singleton
#Component(modules = { TestFlingyModule.class })
public interface TestFlingyComponent extends FlingyComponent
}
#Module
public class TestFlingyModule
So far, it is nearly identical to the example github. When dagger goes to generate the code for the Component builders in src/main, they generate properly. Dagger does not, however, generate code for the Component builders in src/test.
My main build.gradle:
dependencies {
classpath 'com.android.tools.build:gradle:2.1.0-alpha3'
classpath 'com.neenbedankt.gradle.plugins:android-apt:1.5.1'
}
My app/build.gradle
apply plugin: 'com.android.application'
apply plugin: 'com.neenbedankt.android-apt'
android {
# There is obviously more in here, but this is the custom part:
packagingOptions {
exclude 'META-INF/services/javax.annotation.processing.Processor'
}
}
dependencies {
compile 'com.squareup:otto:1.3.8'
compile 'com.android.support:cardview-v7:23.1.1'
compile 'com.android.support:recyclerview-v7:23.1.1'
compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.android.support:design:23.1.1'
compile 'com.squareup.picasso:picasso:2.5.2'
compile 'com.jakewharton:butterknife:7.0.1'
compile 'com.google.dagger:dagger:2.0.1'
apt 'com.google.dagger:dagger-compiler:2.0.1'
compile 'javax.annotation:javax.annotation-api:1.2'
compile 'io.reactivex:rxandroid:1.1.0'
compile 'io.reactivex:rxjava:1.1.0'
testCompile 'com.neenbedankt.gradle.plugins:android-apt:1.4'
testCompile 'junit:junit:4.12'
testCompile 'org.robolectric:robolectric:3.0'
testCompile 'org.mockito:mockito-core:1.10.19'
}
So when I build, I get the DaggerFlingyApplication_FlingyComponent class, but not the DaggerTestFlingyApplication_TestFlingyComponent
Something interesting I noticed is that if I switch the line:
apt 'com.google.dagger:dagger-compiler:2.0.1'
# TO
compile 'com.google.dagger:dagger-compiler:2.0.1'
I see the following when I run ./gradlew compileDebugUnitTestSources:
:app:compileDebugJavaWithJavac
Note: /app/build/generated/source/apt/debug/com/jy/flingy/DaggerFlingyApplication_FlingyComponent.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
:app:preDebugUnitTestBuild UP-TO-DATE
:app:prepareDebugUnitTestDependencies
:app:compileDebugUnitTestJavaWithJavac
Note: /app/build/intermediates/classes/test/debug/com/jy/flingy/DaggerTestFlingyApplication_TestFlingyComponent.java uses unchecked or unsafe operations.
I don't know why it builds to intermediates and I assume that I need the build.gradle file to use apt instead of compile, but I can't seem to figure out how to get this to work. I know that it's absolutely possible.

You need to add following to your build.gradle file for instrumentation test:
androidTestApt 'com.google.dagger:dagger-compiler:<version>'
or for JUnit test:
testApt 'com.google.dagger:dagger-compiler:<version>'
This is required to generate Dagger code for your test components.
EDIT:
If you are using jack tool chain then add following
for android test:
androidTestAnnotationProcessor 'com.google.dagger:dagger-compiler:<version>'
for JUnit tests:
testAnnotationProcessor 'com.google.dagger:dagger-compiler:<version>'
EDIT:
In case you are using kotlin-kapt for Kotlin code use following:
kaptAndroidTest 'com.google.dagger:dagger-compiler:<version>'
or for JUnit test:
kaptTest 'com.google.dagger:dagger-compiler:<version>'
Check this link for more info.

For Android Studio 3 and dagger 2.13 the already mentioned annotation processors are needed:
testAnnotationProcessor 'com.google.dagger:dagger-compiler:2.13'
But also do not forgot to do this for the instrumented test under androidTest:
androidTestAnnotationProcessor'com.google.dagger:dagger-compiler:2.13'
You might get the impression that this alone does not work, because the DaggerXYZ classes are not generated. After hours I found out that the test source generation is only triggered when the tests are executed. If you start a test or androidTest from Android Studio the source generation should be triggered.
If you need this earlier trigger gradle manually:
gradlew <moduledirectory>:compile<Flavor>DebugAndroidTestSources
gradlew <moduledirectory>:compile<Flavor>DebugTestSources
Replace Debug if you run a test in a different build type.
Note:
If you are using multiDexEnable = true you might get an error:
Test running failed: Instrumentation run failed due to
'java.lang.IncompatibleClassChangeError'
Use a different runner in this case:
android {
defaultConfig {
multiDexEnabled true
testInstrumentationRunner "com.android.test.runner.MultiDexTestRunner"

Just to add a bit to the above answer, since there have been some recent changes.
From Android Gradle plugin version 2.2 and above you will no longer use testApt.
So from now on you need to put only this in the build.gradle:
testAnnotationProcessor 'com.google.dagger:dagger-compiler:<version>'
But more than that, what I came here for, is the following: if you need gradle to generate the DaggerComponent classes for you you will have to do a bit extra work.
Open our build.gradle file and AFTER the android section write this:
android.applicationVariants.all { variant ->
if (variant.buildType.name == "debug") {
def aptOutputDir = new File(buildDir, "generated/source/apt/${variant.unitTestVariant.dirName}")
variant.unitTestVariant.addJavaSourceFoldersToModel(aptOutputDir)
assembleDebug.finalizedBy('assembleDebugUnitTest')
}
}
This will create the directory build/generated/source/apt/test/ as a Java classes recipient and the last part will trigger the "assembleDebugUnitTest" task that will finally create those Dagger2 components in the folder that was just created.
Note that this script is just being triggered for the "debug" variant and takes advantage of that build variant using the "assembleDebug" task. If for some reason you need it in other variants just tweak that a bit.
Why Dagger2 does not do this automatically is beyond me, but hey, I am no pro.

If you added kaptAndroidTest for dagger dependencies and still not getting test components when rebuild your project, try running assembleAndroidTest.

Adding to the above solution and adding the testKapt and androidTestKapt for dagger, I had the problem that my modules and components had the wrong imports as a result of missing imports
e.g
import android.support.test.espresso.core.deps.dagger.Module
import android.support.test.espresso.core.deps.dagger.Module
instead of
import dagger.Module
import dagger.Provides
Hope this helps

Hi even after adding all gradle dependenices and annotations if it still doesnt work then you need to run assembleAndroidTest gradle script for this.
Simply make an empty test case and run it. It will do the job for you.
Cheers

If you are using kotlin use "kaptAndroidTest" to generate dagger component for android tests in your build.gradle file.

I ran ./gradlew build from the command line and got information about a missing Provides method that Android Studio was not telling me about.