Question

I have a Component that uses MigLayout as its LayoutManager. It is set to grow inside the JScrollPane to occupy the whole available width. So if I resize the appliation’s frame, the JScrollPane is as wide as the frame is and the inside component is as well.

However, when I shrink the frame, the grown component inside the JScrollPane just keeps its width and does not shrink, so horizontal scrollbars are displayed.

I am aware of JScrollpane needs to shrink its width and implemented the Scrollable-Interface with getScrollableTracksViewportWidth=true but MigLayout does not seem to honor it.

Any advice? thanks

Answer 1

I solved it with following scala-snippet. Scala’s Scrollable is just a fake wrapper, you are supposed to implement the Java-Scrollable…

import javax.swing.JPanel
import javax.swing.{Scrollable => JScrollable}
import javax.swing.BoxLayout
import java.awt.Dimension
import java.awt.Rectangle
import scala.swing.SequentialContainer
import scala.swing.Orientation
import scala.swing.Scrollable
import scala.swing.Panel

class ScrollablePanel extends Panel with SequentialContainer.Wrapper with Scrollable.Wrapper {

  var scrollIncrement: Int = 10
  var blockScrollIncrement: Int = 50

  val allowVerticalScrolling: Boolean   = true
  val allowHorizontalScrolling: Boolean = false

  override lazy val peer = new JPanel with SuperMixin with JScrollable {
    def getPreferredScrollableViewportSize: Dimension =
      getPreferredSize

    def getScrollableTracksViewportHeight: Boolean =
      !allowVerticalScrolling

    def getScrollableTracksViewportWidth: Boolean =
      !allowHorizontalScrolling

    def getScrollableBlockIncrement(visibleRect: Rectangle, orientation: Int, direction: Int): Int =
      scrollIncrement

    def getScrollableUnitIncrement(visibleRect: Rectangle, orientation: Int, direction: Int): Int =
      blockScrollIncrement
  }

  final protected def scrollablePeer: JScrollable = peer
}