Make the output report pane responsive to window resizing

Author: techncl

csv-validator-ui/src/main/scala/uk/gov/nationalarchives/csv/validator/ui/CsvValidatorUi.scala

@@ -47,6 +47,8 @@ import scala.util.{Failure, Success, Try, Using}
  * @author Adam Retter <[email protected]>
  */
 object CsvValidatorUi extends SimpleSwingApplication {
+  var prefSizeHeightChanged = true
+
   override def startup(args: Array[String]) : Unit = {
     try {
       UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName)
@@ -60,7 +62,28 @@ object CsvValidatorUi extends SimpleSwingApplication {
   private lazy val txtCsvFile = new JTextField(30)
   private lazy val txtCsvSchemaFile = new JTextField(30)
 
+  private def changeHeightOfOutputPane(heightDiff: Int): Unit = {
+    // need to normalise the height change by converting it to "rows"
+    val heightChangeAsRows = Math.ceil(heightDiff / 50f).toInt // 30 is just an arbitrary number that seemed to work fine
+    val newHeight = if((txtArReport.rows + heightChangeAsRows) <= 1) txtArReport.rows + 1
+    else if((txtArReport.rows + heightChangeAsRows) > 40) 40
+    else txtArReport.rows + heightChangeAsRows
+
+    // sometimes the size and preferredSize height stay the same even when the window gets larger so just make box size large in this case
+    val finalHeight = if(heightDiff == 0 && !prefSizeHeightChanged) 40 else newHeight
+    txtArReport.rows = Math.abs(finalHeight)
+  }
+
   def top: SJXFrame = new SJXFrame {
+    this.listenTo(this) // add a listener to the window to listen for all changes to the window
+    private var previousHeight = this.preferredSize.height
+    this.reactions += onResize {
+      val heightDiff = this.size.height - this.preferredSize.height
+
+      changeHeightOfOutputPane(heightDiff)
+      prefSizeHeightChanged = previousHeight != this.preferredSize.height
+      previousHeight = this.preferredSize.height
+    }
 
     title = "CSV Validator"
     peer.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE)
@@ -70,11 +93,12 @@ object CsvValidatorUi extends SimpleSwingApplication {
       //handle resizing the main window, when resizing the settings panel
       settings.settingsGroup.reactions += SJXTaskPane.onViewStateChanged {
         val newSize = if(settings.settingsGroup.collapsed) {
-          txtArReport.rows = 35
+          txtArReport.rows = 40
           this.size
         } else {
           txtArReport.rows = 9
-          new Dimension(this.size.getWidth.toInt, (this.size.getHeight + settings.size.getHeight).toInt)
+          val settingsHeight = settings.size.getHeight
+          new Dimension(this.size.getWidth.toInt, (this.preferredSize.getHeight + settingsHeight).toInt)
         }
         this.preferredSize = newSize
         this.pack()
@@ -237,7 +261,7 @@ object CsvValidatorUi extends SimpleSwingApplication {
     }.map(Some(_)).getOrElse(None)
   }
 
-  private val txtArReport = new TextArea(35,30)
+  private val txtArReport = new TextArea()
 
   /**
    * The main UI of the application

csv-validator-ui/src/main/scala/uk/gov/nationalarchives/csv/validator/ui/ScalaSwingHelpers.scala

@@ -9,7 +9,7 @@
 package uk.gov.nationalarchives.csv.validator.ui
 
 import swing._
-import scala.swing.event.{ButtonClicked, Key, KeyPressed, MouseClicked}
+import scala.swing.event.{ButtonClicked, Key, KeyPressed, MouseClicked, UIElementResized}
 import swing.FileChooser.Result
 import swing.GridBagPanel.Anchor
 import java.beans.{PropertyChangeEvent, PropertyChangeListener}
@@ -164,4 +164,8 @@ object ScalaSwingHelpers {
       f(e)
     }
   }
+
+  def onResize(action: => Unit) : Reactions.Reaction = {
+    case evt: UIElementResized => action
+  }
 }