build.sbt

...

libraryDependencies ++= Seq(
  aar("org.macroid" %% "macroid" % "2.0.0-M3"),
  apklib("com.viewpagerindicator" % "library" % "2.4.1"),
  ...
)

// viewpagerindicator includes a spurious copy of support library
dependencyClasspath in Compile ~= { _ filterNot (_.data.getName startsWith "android-support-v4") }

...

FragmentPaging.scala

// some other android imports here
...

import android.support.v4.app.{ Fragment, FragmentManager, FragmentPagerAdapter }
import android.support.v4.view.ViewPager
import com.viewpagerindicator.TitlePageIndicator
import macroid._
import macroid.FullDsl._
import macroid.contrib._
import macroid.contrib.Layouts._

/** An adapter that takes pairs (page title, fragment factory) */
case class PagingAdapter(fm: FragmentManager, frags: Seq[(CharSequence, Ui[Fragment])]) extends FragmentPagerAdapter(fm) {
  def getCount = frags.length
  def getItem(position: Int) = frags(position)._2.get
  override def getPageTitle(position: Int): CharSequence = frags(position)._1
}

/** A trait that provides getTabs method to create a paging layout */
trait FragmentPaging { self: IdGeneration ⇒
  def getTabs(frags: (CharSequence, Ui[Fragment])*)(implicit ctx: ActivityContext, manager: FragmentManagerContext[Fragment, FragmentManager]) = {
    // create an adapter
    val adapter = PagingAdapter(manager.get, frags)
    
    // create a pager
    val pager = w[ViewPager] <~
      id(Id.pager) <~ // it is important to assign an id!
      PagerTweaks.adapter(adapter)

    pager.flatMap { p ⇒
      // create an indicator and attach to the pager
      val indicator = w[TitlePageIndicator] <~
        LpTweaks.matchWidth <~
        BgTweaks.color(Color.BLACK) <~
        Tweak[TitlePageIndicator] { x ⇒
          x.setViewPager(p)
          // other initialization
        }
        
      // create a layout with both incicator and pager
      l[VerticalLinearLayout](indicator, Ui(p))
    }
  }
}

MyActivity.scala

// some other android imports here
...

import android.support.v4.app.FragmentActivity
import macroid._
import macroid.FullDsl._

class MyActivity extends FragmentActivity with Contexts[FragmentActivity] with IdGeneration with FragmentPaging {
  ...
  
  override def onCreate(savedInstanceState: Bundle) = {
    super.onCreate(savedInstanceState)

    setContentView(getUi {
      l[VerticalLinearLayout](
        ...,
        getTabs(
          // list pairs (page title, factory)
          "Fragment 1" → f[Fragment1].factory,
          "Fragment 2" → f[Fragment2].factory,
          ...
        ),
        ...
      )
    })
  }
  
  ...
}

Hey, this is great work. Consider using an Upper Bound on the getTabs method like this:

def getTabs[F <: Fragment](frags: (CharSequence, Ui[F])*)(implicit ctx: ActivityContext, manager: FragmentManagerContext[F, FragmentManager]) = {

This will allow user to use their own Fragments instead of a blank vanilla fragment