After struggling and struggling and looking for help here and there, I discovered that ./gradlew app:dependencies command was providing important output to solve the error.
First of all, the error is Program type already present: androidx.annotation.AnimRes
Program type already present means there is a naming conflict, and in this case the androidx.annotation library, which is use by several libraries.That is other libraries contain androidx.annotation library as a transitive dependency. To see this libraries, i opened the terminal from my project’s root folder(my OS is Ubuntu) and run ./gradlew app:dependencies command. It produced a long list of configurations and their dependences. below is an extract.
debugCompileClasspath - Resolved configuration for compilation for variant: debug
+--- androidx.databinding:databinding-common:3.3.0-alpha07
+--- androidx.databinding:databinding-runtime:3.3.0-alpha07
| +--- androidx.lifecycle:lifecycle-runtime:2.0.0-alpha1 -> 2.0.0-rc01
| | +--- androidx.lifecycle:lifecycle-common:2.0.0-rc01
| | | \--- androidx.annotation:annotation:1.0.0-rc01 -> 1.0.0-rc02
| | +--- androidx.arch.core:core-common:2.0.0-rc01
| | | \--- androidx.annotation:annotation:1.0.0-rc01 -> 1.0.0-rc02
| | \--- androidx.annotation:annotation:1.0.0-rc01 -> 1.0.0-rc02
| +--- androidx.collection:collection:1.0.0-alpha1 -> 1.0.0-rc02
| | \--- androidx.annotation:annotation:1.0.0-rc02
| \--- androidx.databinding:databinding-common:3.3.0-alpha07
+--- androidx.databinding:databinding-adapters:3.3.0-alpha07
| +--- androidx.databinding:databinding-common:3.3.0-alpha07
| \--- androidx.databinding:databinding-runtime:3.3.0-alpha07 (*)
The above extract shows some of dependencies for debugCompileClasspath configuration.We can see that androidx.databinding:databinding-runtime:3.3.0-alpha07 contains androidx.annotation:annotation:1.0.0-rc02 as a transitive dependency.
It also contains androidx.lifecycle:lifecycle-runtime:2.0.0-alpha1 which in turns contain androidx.annotation:annotation:1.0.0-rc01.
androidx.annotation:annotation:1.0.0-rc01 -> 1.0.0-rc02 means that version 1.0.0-rc02 will be used instead of version 1.0.0-rc01 .
Below is another extract from the same long output produced by ./gradlew app:dependencies
kapt
+--- androidx.lifecycle:lifecycle-compiler:2.0.0-alpha1
| +--- androidx.lifecycle:lifecycle-common:2.0.0-alpha1
| | \--- androidx.annotation:annotation:1.0.0-alpha1
| +--- org.jetbrains.kotlin:kotlin-stdlib:1.2.41
| | \--- org.jetbrains:annotations:13.0
| +--- com.google.auto:auto-common:0.6
| | \--- com.google.guava:guava:18.0 -> 23.3-jre
| | +--- com.google.code.findbugs:jsr305:1.3.9
| | +--- com.google.errorprone:error_prone_annotations:2.0.18
| | +--- com.google.j2objc:j2objc-annotations:1.1
| | \--- org.codehaus.mojo:animal-sniffer-annotations:1.14
| \--- com.squareup:javapoet:1.8.0
From the above, we can see that androidx.lifecycle:lifecycle-compiler:2.0.0-alpha1 contains version 1.0.0-alpha1 of androidx.annotation:annotation
This means at the end, my module app will have two versions 1.0.0-alpha1 and 1.0.0-rc02 which makes build to fail.
To solve this error, i just removed the transitive dependencies by adding the below block of code in my app’s build.gradle
configurations {
compile.exclude group: 'androidx.annotation', module: 'annotation'
}
So my app’s build.gradle will look like this
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
apply plugin: 'realm-android'
android {
//bla bla bla
}
configurations {
compile.exclude group: 'androidx.annotation', module: 'annotation'
}
dependencies {
// bla bla bla
}
After that, i just synced,cleaned and rebuild my project.