Develop Reference

Kotlin MyClass.class.java Unresolved reference: java

In Java Android we use MyActivity.class to start a new activity. I was playing with Android Studio 3 beta1 and tried to convert it to kotlin. It gets converted to MyActivity::class.java but this doesn't compile. It gives me Unresolved reference: java. What would be the correct equivalent?
Project Build.gradle:
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.0-beta1'
classpath 'com.google.gms:google-services:3.0.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
maven { url "https://jitpack.io" }
}
}
App Build.gradle:
apply plugin: 'com.android.application'
android {
signingConfigs {
}
compileSdkVersion 25
buildToolsVersion "25.0.2"
lintOptions {
abortOnError false
}
defaultConfig {
vectorDrawables.useSupportLibrary = true
applicationId "app"
minSdkVersion 15
targetSdkVersion 25
versionCode 104
versionName "4.0.11"
}
buildTypes {
release {
minifyEnabled true
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
debug {
minifyEnabled false
}
}
flavorDimensions "mode"
productFlavors {
free {
dimension "mode"
}
paid {
dimension "mode"
applicationId "app.paid"
}
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:25.3.1'
compile 'com.android.support:support-v4:25.3.1'
compile 'com.android.support:design:25.3.1'
compile 'com.android.support:recyclerview-v7:25.3.1'
compile 'com.android.support:cardview-v7:25.3.1'
compile 'com.google.android.gms:play-services-ads:10.2.6'
releaseCompile 'ch.acra:acra:4.9.1'
// compile 'ch.acra:acra:4.9.1'
compile 'com.google.firebase:firebase-core:10.2.6'
compile 'com.google.firebase:firebase-database:10.2.6'
compile 'com.google.firebase:firebase-auth:10.2.6'
compile 'com.google.android.gms:play-services-auth:10.2.6'
compile 'com.github.frangsierra:rx2firebase:1.1.3'
}
apply plugin: 'com.google.gms.google-services'

Try adding following changes in your gradle file.
Add classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.1.3-2" in your project build.gradle file.
build.gradle(:project)
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.0-beta1'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.1.3-2" // New
classpath 'com.google.gms:google-services:3.0.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
...
...
And add
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-android'
two lines in app build.gradle file.
build.gradle(:app)
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android-extensions' // New
apply plugin: 'kotlin-android' // New
android {
...
...
...
...
}
dependencies {
...
...
}
apply plugin: 'com.google.gms.google-services'
This must solve your problem as i have updated My Android Studio to 3.0 beta 1 and having so issues.
I Hope this helps.

I think this was an bug. I just updated to beta2 an the problem was solved.

Cannot invoke method version() on null object

i'm trying to use the Jgrapht library but it needs lambdas...
Here's my code:
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
maven {
url "https://plugins.gradle.org/m2/"
}
jcenter()
}
dependencies {
classpath "gradle.plugin.me.tatarka:gradle-retrolambda:3.3.0"
classpath 'com.android.tools.build:gradle:2.2.1'
}
}
allprojects {
repositories {
jcenter()
mavenCentral()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
And the :app
apply plugin: "me.tatarka.retrolambda" version "3.3.0"
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "24.0.3"
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
defaultConfig {
applicationId "it.univpm.gruppoids.iotforemergencyandnavigation"
minSdkVersion 16
targetSdkVersion 23
versionCode 1
versionName "1.0"
jackOptions {
enabled true
}
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.4.0'
compile 'com.android.support:design:23.4.0'
compile 'com.android.support:support-v4:23.4.0'
compile 'com.journeyapps:zxing-android-embedded:3.2.0#aar'
compile 'com.google.zxing:core:3.2.1'
compile 'org.jgrapht:jgrapht-core:1.0.0'
}
The error is: Error:(1, 0) Cannot invoke method version() on null object
Open File
Where and what is the error? thanks

You're mixing two kinds of syntaxes. Use either
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath "gradle.plugin.me.tatarka:gradle-retrolambda:3.3.0"
}
}
apply plugin: 'me.tatarka.retrolambda'
or
plugins {
id "me.tatarka.retrolambda" version "3.3.0"
}
(gradle-retrolambda README), see also the gradle documentation.

I have the same issue.
You'll need to update a few things:
android/build.gradle:
i) classpath 'com.google.gms:google-services:4.0.1'
ii) Make sure google() appears above jcenter() in both buildscripts and allprojects
android/app/build.gradle:
Update Android libs to the latest specified here:
https://firebase.google.com/support/release-notes/android#20180523
if you have other libraries (for me, it's firebase) make sure to check build.gradle of the libraries, too.

Retrolambda Error:Cannot get property 'destinationDir' on null object

I am trying to use retrolambda in my application but I face issues
build.gradle project
buildscript {
repositories {
jcenter()
mavenLocal()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.1.3'
classpath 'com.neenbedankt.gradle.plugins:android-apt:1.8'
classpath 'me.tatarka:gradle-retrolambda:3.2.5'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
mavenLocal()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
build.gradle app
apply plugin: 'com.android.application'
apply plugin: 'com.neenbedankt.android-apt'
apply plugin: 'me.tatarka.retrolambda'
android {
compileSdkVersion 23
buildToolsVersion "24.0.1"
defaultConfig {
applicationId "psystem.co.reaya"
minSdkVersion 15
targetSdkVersion 23
versionCode 1
versionName "1.0"
multiDexEnabled true
jackOptions {
enabled true
}
}
dexOptions {
preDexLibraries false
javaMaxHeapSize "4g"
incremental true
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.google.code.gson:gson:2.4'
retrolambdaConfig 'net.orfjackal.retrolambda:retrolambda:+'
compile 'com.android.support:multidex:1.0.1'
}
my tries to fix the issue remove jack options , I got this error `org.gradle.execution.TaskSelectionException: Task ',' not found in root project 'Reaya'.`
any one can help me to fix my issue
thank you

1.update the Android studio to 2.1 or higher version;
2.delete the "apply plugin: 'me.tatarka.retrolambda'"
Try it!

removing the lines apply plugin: 'me.tatarka.retrolambda' worked for me.

Might stick to retrolambda. Some discussions on jack can be found here

Gradle/Android Studio doesn't pull dependencies from specified repositories

NOTE: This is a followup of my last question that still remained unsolved.
I'm using a fully updated AndroidStudio with the default gradle support.
Android Studio can self update (thus sees Internet for sure).
I have no reason to beleive that Gradle can't reach the internet nor any error that could imply that, and I verified that it's not on offline mode.
Here's my Here's my top-level build.gradle:
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.5.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
maven { url "https://jitpack.io" }
}
}
and here's my app/build.gradle:
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "23.0.0"
defaultConfig {
applicationId "com.domain.app"
minSdkVersion 19
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:23.0.0'
compile 'com.github.jitpack:android-example:1.0.4'
}
Here I'm trying to pull the jitpack.io sample, and still getting:
Error:(31, 13) Failed to resolve: com.github.jitpack:android-example:1.0.4
without any additional information.

try this :
buildscript {
repositories {
jcenter()
mavenCentral()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.5.0'
}
}
allprojects {
repositories {
jcenter()
}
}
Then in your app/build.gradle :
apply plugin: 'com.android.application'
repositories {
maven { url "https://jitpack.io" }
flatDir {
dirs 'libs'
}
}
android {
compileSdkVersion 23
buildToolsVersion "23.0.0"
defaultConfig {
applicationId "com.domain.app"
minSdkVersion 19
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:23.0.0'
compile 'com.github.jitpack:android-example:1.0.4'
}

Its not the problem of android studio, To inform you
Neither
compile 'com.github.jitpack:android-example:1.0.4'
Nor
compile 'com.github.User:Repo:Tag'
Both doesn't compile now, Because it's no longer available in the The Central Repository. You don't have any ways rather than seeing the codes inside.

Gradle couldn't find com.android.databinding:dataBinder:1.0-rc0

This is an old question which is irrelevant today. See Android developer's instruction. Applying Databinding to your projects is a lot easier now than four years ago.
As I am going over Android Data binding Guide from https://developer.android.com/tools/data-binding/guide.html. I have made sure I am running Android Studio 1.3 (canary version).
Following the guidelines, I get this error:
Gradle sync failed: could not find com.android.databinding:library:1.0-rc0
Has anyone else have the same problem? Thanks for your help.
App build.gradle
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.3.0-beta1'
classpath "com.android.databinding:dataBinder:1.0-rc0"
}
}
allprojects {
repositories {
jcenter()
}
}
Module build.graddle
apply plugin: 'com.android.application'
apply plugin: 'com.android.databinding'
apply plugin: 'android-apt'
def AAVersion = '3.3'
def MyProject = 'com.commonsware.android.frw.filesdemo'
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath 'com.neenbedankt.gradle.plugins:android-apt:1.4'
}
}
repositories {
mavenCentral()
}
apt {
arguments {
androidManifestFile variant.outputs[0].processResources.manifestFile
resourcePackageName "$MyProject"
}
}
android {
compileSdkVersion 22
buildToolsVersion "22"
defaultConfig {
applicationId "$MyProject"
minSdkVersion 17
targetSdkVersion 22
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
packagingOptions{
exclude 'META-INF/LICENSE'
exclude 'META-INF/NOTICE'
exclude 'META-INF/services/com.fasterxml.jackson.core.JsonFactory'
}
dexOptions {
preDexLibraries = false
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_7
targetCompatibility JavaVersion.VERSION_1_7
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.0.0'
compile "com.squareup:otto:1.3.6"
compile "commons-io:commons-io:+"
compile 'com.fasterxml.jackson.jr:jackson-jr-all:2.5.0'
compile 'com.astuetz:pagerslidingtabstrip:1.0.1'
apt "org.androidannotations:androidannotations:$AAVersion"
compile "org.androidannotations:androidannotations-api:$AAVersion"
}

I had this problem and solved it by adding "jcenter" under allprojects.repositories in my top-level build.gradle (I had been using mavenCentral).
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.3.0'
classpath 'com.android.databinding:dataBinder:1.0-rc1'
}
}
allprojects {
repositories {
mavenCentral()
jcenter() // <=== *** Adding this fixed it ***
}
}

I got errors when I sync build.gradle files.
Error:Failed to resolve: com.android.databinding:library:1.0-rc0
Error:Failed to resolve: com.android.databinding:adapters:1.0-rc0
And I finally found the solution.
dependencies {
// instead of the below pathes...
//classpath "com.android.tools.build:gradle:1.3.0-beta2"
//classpath "com.android.databinding:dataBinder:1.0-rc0"
// I used the following classpathes.... It works!
classpath "com.android.tools.build:gradle:1.3.+"
classpath "com.android.databinding:dataBinder:1.+"
}

By looking at your error Gradle couldn't find com.android.databinding:dataBinder:1.0-rc0 you should try this instead,
classpath "com.android.databinding:dataBinder:1.0-rc1"
To use DataBinding follow all these steps.
Update your Android Studio to Android Studio 1.3 version.
To set up your application to use data binding, add data
binding to the class path of your top-level build.gradle file,
right below "android".
dependencies {
classpath "com.android.tools.build:gradle:1.3"
classpath "com.android.databinding:dataBinder:1.0-rc1"
}
Then make sure jcenter is in the repositories list for your projects
in the top-level build.gradle file.
allprojects {
repositories {
jcenter()
}
}
In each module you want to use data binding, apply the plugin right
after android plugin.
apply plugin: 'com.android.application'
apply plugin: 'com.android.databinding'
Clean and build your app.
Complete code
top-level build.gradle file,
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.3'
classpath "com.android.databinding:dataBinder:1.0-rc1"
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
}
}
module-level build.gradle file,
apply plugin: 'com.android.application'
apply plugin: 'com.android.databinding'
android {
compileSdkVersion 22
buildToolsVersion "22.0.1"
defaultConfig {
applicationId "com.example.packagename"
minSdkVersion 15
targetSdkVersion 22
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-v7:22.2.1'
}
For more detail Data Binding Guide.
For Complete demo Data Binding Android

Make sure you have Android Studio 1.3 or higher
Your project build.gradle should look something like this:
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.3.0-beta1'
classpath "com.android.databinding:dataBinder:1.0-rc0"
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
}
}
And your module build.gradle should look something like this:
apply plugin: 'com.android.application'
apply plugin: 'com.android.databinding'
android {
compileSdkVersion 22
buildToolsVersion "22.0.1"
defaultConfig {
applicationId "com.my.appId"
minSdkVersion 15
targetSdkVersion 22
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
}
I had a problem where I was targeting M Preview so nothing worked. Once I changed the build tools to 22.0.1, and the targetSdkVersion to 22, everything worked.

I had the same issue and solved it by updating android sdk tools to 24.3.3.

Update for latest Android Studio & latest Gradle
You don't need to add databinding:dataBinder dependency now. Just enable dataBinding in app level build.gradle in android tag.
android
{
...
dataBinding {
enabled = true
}
...
}

As the Documentation said
To use data binding, Android Plugin for Gradle 1.5.0-alpha1 or higher
is required.
I have added the following line to build.gradle project :
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
jcenter()
}
dependencies {
classpath "com.android.tools.build:gradle:1.5.0-beta2"
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
and then add the :
dataBinding {
enabled = true
}
to your build.graddle module app like this :
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "23.0.1"
defaultConfig {
applicationId "gujarat.databinding"
minSdkVersion 16
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
dataBinding {
enabled = true
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.android.support:support-v4:23.1.1'
}

Please, try to change classpath to 'com.android.tools.build:gradle:1.3.0-beta2' and set buildToolsVersion "23 rc2".
Don't forget to update SDK packages via SDK manager before doing that.
Here you can find more information about Android Preview SDK: Set Up the Preview SDK

I had an identical issue, and solved it by removing the plugin for android-apt. Not sure what's conflicting there, but something is.

You should update your SDK and It will resolve this issue.

You should add
classpath 'com.android.tools.build:gradle:1.3.0'
classpath "com.android.databinding:dataBinder:1.0-rc0"
build.grade which in project Directory.
then Sync the gradle

Sync your project after adding classpath