Avoid lock when exporting the view in GUIWorkspace

Author: mrerrormessage

src/main/scala/RecordView.scala

@@ -1,7 +1,10 @@
 package org.nlogo.extensions.vid
 
+import java.awt.image.BufferedImage
+
 import org.nlogo.core.Syntax
-import org.nlogo.api.{ Argument, Context, Command, ExtensionException }
+import org.nlogo.window.GUIWorkspace
+import org.nlogo.api.{ Argument, Context, Command, ExtensionException, ReporterRunnable }
 
 class RecordView(recorder: Recorder) extends Command {
 
@@ -10,6 +13,13 @@ class RecordView(recorder: Recorder) extends Command {
   def perform(args: Array[Argument], context: Context): Unit = {
     if (! recorder.isRecording)
       throw new ExtensionException("vid: recorder not started")
-    recorder.recordFrame(context.workspace.exportView)
+    context.workspace match {
+      case gw: GUIWorkspace =>
+        val exportedView = gw.waitForResult(new ReporterRunnable[BufferedImage] {
+          override def run(): BufferedImage = gw.exportView
+        })
+        recorder.recordFrame(exportedView)
+      case _ => recorder.recordFrame(context.workspace.exportView)
+    }
   }
 }