How to create a custom screen with the atlassian SDK?

[S T]

Hey there

I want to create a custom screen with the Atlassian SDK where I can add a custom field I created. I know there are different solutions out there(I am following this one: https://community.atlassian.com/t5/Answers-Developer-Questions/Adding-Field-Screens-Programatically-in-a-plugin/qaq-p/535263 ), but as far as I seen, every one of them uses the FieldScreenImpl.

I try to use 

import com.atlassian.jira.issue.fields.screen.FieldScreenImpl;

but Intellij tells me, that it cannot resolve symbol. 
Do I do something wrong, or did they change FieldScreenImp to something else? 
Other import statements like 

import com.atlassian.jira.issue.fields.screen.FieldScreen;

do work well.

Help is really appreciated, thank you.

[Jette und Patrick]

You have to insert following dependeny to pom.xml:

<dependency>
    <groupId>com.atlassian.jira</groupId>
    <artifactId>jira-core</artifactId>
    <version>${jira.version}</version>
    <scope>provided</scope>
</dependency>

This solved it for me.

[Jette und Patrick]

I am facing the same Issue with all classes that end on Impl... Any suggestions?