perform GUI construction on event dispatch thread, not on main thread

noticed the issue thanks to the changes in ReactiveX/RxJava#883

RxJavaSwingThreads/src/main/java/RxJavaSwingThreads.java

@@ -38,10 +38,6 @@ public class RxJavaSwingThreads extends JFrame {
 
 	// all Strings ever present in textField (duplicates because of key down/up)
 	Observable<String> textFieldContents;
-
-	public static void main(String[] args) {
-		new RxJavaSwingThreads();
-	}
 
 	public RxJavaSwingThreads() {
 		makeLayout();
@@ -53,11 +49,9 @@ public String call(KeyEvent e) {
 			}
 		});
 
-		checkNotOnUiThread("constructor");
-
-		// spams System.out 
-		// subscriptionsTouchingOnlySystemOut();
-
+		checkOnUiThread("constructor");
+
+		subscriptionsTouchingOnlySystemOut();
 		subscriptionsTouchingUi();
 	}
 
@@ -70,16 +64,16 @@ public void call(String s) {
 				textArea.setText(textArea.getText() + "\n" + s);
 			}
 		});
-		
+
 		// Subscription 2 (bad)
 		// This is BAD because UI is modified on SecondsImpl's thread instead of event dispatching thread!
 		seconds.subscribe(new Action1<Long>() {
 			public void call(Long n) {
 				checkOnUiThread("title-changing-BAD-deactivated");
-				//RxSwing2.this.setTitle("t = " + n);				
+				//RxJavaSwingThreads.this.setTitle("t = " + n + "s");
 			}
 		});
-		
+
 		// Subscription 3 (correct)
 		// The correct way to achieve what we tried above
 		seconds.observeOn(SwingScheduler.getInstance()).subscribe(new Action1<Long>(){
@@ -184,6 +178,15 @@ public void mouseEntered(MouseEvent arg0) {}
 			public void mouseClicked(MouseEvent arg0) {}
 		});
 	}
-
+
+	public static void main(String[] args) {
+		// Schedule a job for the event-dispatching thread: creating and showing
+		// this application's GUI.
+		javax.swing.SwingUtilities.invokeLater(new Runnable() {
+			public void run() {
+				new RxJavaSwingThreads();
+			}
+		});
+	}
 }
 

RxScalaDict/src/main/scala/RxScalaDict.scala

@@ -7,7 +7,6 @@ import javax.swing.JFrame
 import javax.swing.JScrollPane
 import javax.swing.JTextArea
 import javax.swing.JTextField
-import rx.schedulers.SwingScheduler
 import rx.lang.scala.Observable
 import rx.lang.scala.Scheduler
 import rx.lang.scala.schedulers._
@@ -30,14 +29,17 @@ class Win1 extends JFrame {
       event.getComponent().asInstanceOf[JTextField].getText()
 
     val throttled = input.distinctUntilChanged.filter(_.length >= 2).throttleWithTimeout(500 millis)
-        
+
     throttled.subscribe(println(_))
 
-    throttled.observeOn(IOScheduler()).map(
-        LookupInWordNet.matchPrefixInWordNet(_)
-    // for SwingScheduler, there is no Scala Wrapper yet, so we have to convert explicitly
-    // from Java Scheduler to Scala Scheduler:
-    ).observeOn(new Scheduler{ val asJavaScheduler = SwingScheduler.getInstance}).subscribe(
+    throttled
+      // Switch from SwingScheduler to IOScheduler:
+      .observeOn(IOScheduler())
+      // Do IO which might take much time:
+      .map(LookupInWordNet.matchPrefixInWordNet(_))
+      // Switch back from IOScheduler to SwingScheduler:
+      .observeOn(SwingScheduler)
+      .subscribe(
         matches => {
           ThreadLogger.log("updating text in textArea")
           textArea.setText(matches.mkString("\n"))
@@ -54,14 +56,27 @@ class Win1 extends JFrame {
 	add(textField, BorderLayout.NORTH)
 	add(sp, BorderLayout.CENTER)
 	setSize(400, 400)
+	setTitle("RxScalaDict")
 
 	setVisible(true)
 	setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)
   }
-
+
+  // For SwingScheduler, there is no Scala Wrapper yet, so we have to convert explicitly
+  // from Java Scheduler to Scala Scheduler:
+  val SwingScheduler: Scheduler = new Scheduler {
+    val asJavaScheduler = rx.schedulers.SwingScheduler.getInstance
+  }
 }
 
-object RxScalaDict extends App {  
-  new Win1().run
+object RxScalaDict {
+  def main(args: Array[String]): Unit = {
+    // Schedule a job for the event-dispatching thread: creating and showing this application's GUI.
+    javax.swing.SwingUtilities.invokeLater(new Runnable {
+      override def run(): Unit = {
+        new Win1().run
+      }
+    });
+  }
 }
 

RxScalaKonami/src/main/scala/Konami.scala

@@ -51,7 +51,14 @@ class Win1 extends JFrame {
   }  
 }
 
-object Konami extends App {  
-  new Win1().run
+object Konami {
+  def main(args: Array[String]): Unit = {
+    // Schedule a job for the event-dispatching thread: creating and showing this application's GUI.
+    javax.swing.SwingUtilities.invokeLater(new Runnable {
+      override def run(): Unit = {
+        new Win1().run
+      }
+    });
+  }
 }
 

RxScalaPaint/src/main/scala/Paint.scala

@@ -106,7 +106,14 @@ object MouseEventSource {
   )
 }
 
-object Paint extends App {  
-  new Win1().run
+object Paint {  
+  def main(args: Array[String]): Unit = {
+    // Schedule a job for the event-dispatching thread: creating and showing this application's GUI.
+    javax.swing.SwingUtilities.invokeLater(new Runnable {
+      override def run(): Unit = {
+        new Win1().run
+      }
+    });
+  }
 }
 

RxScalaPortScan/src/main/scala/PortScanFutures.scala

@@ -21,7 +21,7 @@ trait Result
 case class Open(s: Socket) extends Result
 case class Closed(port: Int) extends Result
 
-object PortScanFutures extends App {
+object PortScanFutures {
 
   import FutureExtensions._
 
@@ -34,27 +34,26 @@ object PortScanFutures extends App {
   // threads of the thread pool are terminated after being idle for 60 seconds.
   // Without this line, the app terminates before all open ports are printed!
   implicit val ec = ExecutionContext.fromExecutorService(Executors.newCachedThreadPool())
-
-  Observable.from(1 to 65536).flatMap(port =>
-    future {
-      try {
-        Open(new Socket(host, port))
-      } catch {
-        case e: Exception => Closed(port)
-      }
-    }.asObservable
-  ).subscribe(
-    res => res match {
-      case y: Open =>
-        println("Port " + y.s.getPort + " is open")
-        y.s.close
-      case y: Closed =>
-    },
-    err => err.printStackTrace(),
-    () => println("Done.")
-  )
-}
 
+  def main(args: Array[String]): Unit = {
+    Observable.from(1 to 65536).flatMap(port =>
+      future {
+        try {
+          Open(new Socket(host, port))
+        } catch {
+          case e: Exception => Closed(port)
+        }
+      }.asObservable).subscribe(
+      res => res match {
+        case y: Open =>
+          println("Port " + y.s.getPort + " is open")
+          y.s.close
+        case y: Closed =>
+      },
+      err => err.printStackTrace(),
+      () => println("Done."))
+  }
+}
 
 // Extend Future with the asObservable method
 object FutureExtensions {

RxScalaPortScan/src/main/scala/PortScanThreadpool.scala

@@ -9,32 +9,33 @@ import scala.language.implicitConversions
 import rx.lang.scala.Observable
 import rx.lang.scala.schedulers.IOScheduler
 
-object PortScanThreadPool extends App {
+object PortScanThreadPool {
 
   // Port scanning results
   trait Result
   case class Open(s: Socket) extends Result
   case class Closed(port: Int) extends Result
 
   val host = "localhost"
-    
+
   def scanPort(port: Int): Result = try {
     Open(new Socket(host, port))
   } catch {
     case e: Exception => Closed(port)
   }
 
-  Observable.from(1 to 65536)
-    .flatMap(port => Observable.just(port).observeOn(IOScheduler()).map(scanPort(_)))
-    // convert to blocking because otherwise app may terminate before all threads of 
-    // Schedulers.threadPoolForIO have completed their work (these threads are daemons)
-    .toBlocking
-    .foreach(res => res match {
-      case y: Open =>
-        println("Port " + y.s.getPort + " is open")
-        y.s.close
-      case y: Closed =>
-    })
-  println("Done.")
-
+  def main(args: Array[String]): Unit = {
+    Observable.from(1 to 65536)
+      .flatMap(port => Observable.just(port).observeOn(IOScheduler()).map(scanPort(_)))
+      // convert to blocking because otherwise app may terminate before all threads of 
+      // Schedulers.threadPoolForIO have completed their work (these threads are daemons)
+      .toBlocking
+      .foreach(res => res match {
+        case y: Open =>
+          println("Port " + y.s.getPort + " is open")
+          y.s.close
+        case y: Closed =>
+      })
+    println("Done.")
+  }
 }

RxScalaTooltip/src/main/scala/Tooltip.scala

@@ -101,7 +101,14 @@ class Win1 extends JFrame {
   implicit def point2javaAwtPoint(p: Point): java.awt.Point = new java.awt.Point(p.x, p.y)
 }
 
-object Tooltip extends App {  
-  new Win1().run
+object Tooltip {
+  def main(args: Array[String]): Unit = {
+    // Schedule a job for the event-dispatching thread: creating and showing this application's GUI.
+    javax.swing.SwingUtilities.invokeLater(new Runnable {
+      override def run(): Unit = {
+        new Win1().run
+      }
+    });
+  }
 }
 

RxScalaVoltageControl/src/main/scala/VoltageControl.scala

@@ -153,7 +153,14 @@ object SwingSource {
 
 }
 
-object VoltageControl extends App {  
-  new Win1().run
+object VoltageControl {  
+  def main(args: Array[String]): Unit = {
+    // Schedule a job for the event-dispatching thread: creating and showing this application's GUI.
+    javax.swing.SwingUtilities.invokeLater(new Runnable {
+      override def run(): Unit = {
+        new Win1().run
+      }
+    });
+  }
 }