Fixed issue #178: when FileChooser.showOpenMultipleDialog was used an…

…d user cancelled selection an NPE was thrown.

Also clatify in Scaladoc that null may be returned.

scalafx/src/main/scala/scalafx/stage/DirectoryChooser.scala

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2014, ScalaFX Project
+ * Copyright (c) 2011-2015, ScalaFX Project
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -59,6 +59,8 @@ class DirectoryChooser(override val delegate: jfxs.DirectoryChooser = new jfxs.D
 
   /**
    * Shows a new directory selection dialog.
+   *
+   * @return the selected directory or null if no directory has been selected
    */
   def showDialog(ownerWindow: Window): File = delegate.showDialog(ownerWindow)
 }

scalafx/src/main/scala/scalafx/stage/FileChooser.scala

@@ -129,16 +129,25 @@ class FileChooser(override val delegate: jfxs.FileChooser = new jfxs.FileChooser
 
   /**
    * Shows a new file open dialog.
+   *
+   * @return the selected file or null if no file has been selected
    */
   def showOpenDialog(ownerWindow: Window): File = delegate.showOpenDialog(ownerWindow)
 
   /**
    * Shows a new file open dialog in which multiple files can be selected.
+   *
+   * @return the selected files or null if no file has been selected
    */
-  def showOpenMultipleDialog(ownerWindow: Window): Seq[File] = delegate.showOpenMultipleDialog(ownerWindow)
+  def showOpenMultipleDialog(ownerWindow: Window): Seq[File] = {
+    val selection = delegate.showOpenMultipleDialog(ownerWindow)
+    if (selection != null) selection else null.asInstanceOf[Seq[File]]
+  }
 
   /**
    * Shows a new file save dialog.
+   *
+   * @return the selected file or null if no file has been selected
    */
   def showSaveDialog(ownerWindow: Window): File = delegate.showSaveDialog(ownerWindow)
 

scalafx/src/test/scala/issues/issue178/MultipleFileChooserDemo.scala

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2011-2015, ScalaFX Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the ScalaFX Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE SCALAFX PROJECT OR ITS CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package issues.issue178
+
+import scala.language.implicitConversions
+import scalafx.Includes._
+import scalafx.application.JFXApp
+import scalafx.application.JFXApp.PrimaryStage
+import scalafx.geometry.Insets
+import scalafx.scene.Scene
+import scalafx.scene.control.Button
+import scalafx.scene.layout.VBox
+import scalafx.stage.FileChooser
+
+/**
+ * Demo for Issue #178: FileChooser does not handle a the value returned when the user cancels file selection.
+ * If FileChooser.showOpenMultipleDialog was used and user cancelled selection an NPE was thrown.
+ *
+ */
+object MultipleFileChooserDemo extends JFXApp {
+
+  stage = new PrimaryStage {
+    scene = new Scene {
+      title = "Demo for Issue #178"
+      root = new VBox {
+        padding = Insets(12)
+        children = new Button {
+          text = "Open file chooser and select multiple files or Cancel"
+          onAction = handle {
+            val fc = new FileChooser()
+            val selection = fc.showOpenMultipleDialog(stage)
+
+            println("Selection: " + selection)
+          }
+        }
+      }
+    }
+  }
+
+}