Start kotlin activity *.kt from java activity *.java?

Question

Invalidate Caches/ restart... helps me!

My code in java class is:

Intent intent = new Intent(view.getActivity(), AddPaymentActivity.class);
view.getActivity().startActivity(intent);

AddPaymentActivity has kotlin extention .kt
Got error java.lang.NoClassDefFoundError

Answer 1

File -> Invalidate Caches/ restart...

Answer 2

In my case, I forgot to add

classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"

and

apply plugin: 'kotlin-android'
...
compile "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"

to build.gradle

Example

project build.gradle

...
buildscript {
  ext.kotlin_version = '1.1.51'
  dependencies {
    classpath 'com.android.tools.build:gradle:3.0.1'
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"

    ...
  }
}

allprojects {
  repositories {
    jcenter()
    google()
  }
}

app build.gradle

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
...

dependencies {
  ...
  compile "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
}