Can't run JavaFX - Kotlin app - javafx

Question

I can't run my javafx - kotlin app.
My Starter class
class Starter : Application() {
override fun start(primaryStage: Stage?) {
val root : Parent = FXMLLoader.load(javaClass.getResource("view/main.fxml"))
primaryStage?.title = "Title"
primaryStage?.scene = Scene(root)
primaryStage?.show()
}
fun main(args: Array<String>) {
launch(args)
}
}
I can't pass the param "args" to "launch" method because compiler says:
Error:(19, 9) Kotlin: None of the following functions can be called
with the arguments supplied: public open fun launch(p0: Class!, vararg p1: String!): Unit defined in
javafx.application.Application public open fun launch(vararg p0:
String!): Unit defined in javafx.application.Application
If I trying call "launch" method without params I have following Exception
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498) at
sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.NullPointerException at
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498) at
com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
at
com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
... 5 more

Answer 1

You need to use spread operator
fun main(args: Array<String>) {
Application.launch(Starter::class.java, *args)
}