Add simple example with thread and runOnUiThread usage.

Manifest.txt

@@ -128,6 +128,7 @@ examples/textedit/commands.rb
 examples/textedit/helpwindow.rb
 examples/textedit/prefdialog.rb
 examples/textedit/textedit.rb
+examples/thread.rb
 examples/unicode.rb
 ext/fox16_c/FXRbApp.cpp
 ext/fox16_c/FXRbDataTarget.cpp

examples/thread.rb

+#!/usr/bin/env ruby
+
+require 'fox16'
+
+class ThreadedWindow < Fox::FXMainWindow
+  include Fox
+
+  def initialize(app)
+    # Call the base class initializer first
+    super(app, "Threaded Widget Test", :opts => DECOR_ALL, width: 200, height: 500)
+
+    @vframe = FXVerticalFrame.new(self,
+      FRAME_SUNKEN|FRAME_THICK|LAYOUT_FILL_X|LAYOUT_FILL_Y, :padding => 0) do |frame|
+      FXButton.new(frame, "Klick to add", opts: FRAME_RAISED|FRAME_THICK|LAYOUT_FILL_X) do |button|
+        button.connect(SEL_COMMAND, method(:on_button_clicked))
+      end
+    end
+  end
+
+  def on_button_clicked(sender, sel, ptr)
+    FXHorizontalFrame.new(@vframe,
+      FRAME_SUNKEN|FRAME_THICK|LAYOUT_FILL_X|LAYOUT_FILL_Y, :padding => 10) do |frame|
+
+      label = FXLabel.new frame, "..."
+
+      Thread.new do
+        50.times do |seconds|
+          runOnUiThread do
+            label.text = "#{(50 - seconds)/10.0} seconds to remove"
+          end
+          sleep 0.1
+        end
+
+        runOnUiThread do
+          @vframe.removeChild(frame)
+          @vframe.create; @vframe.show; @vframe.recalc
+        end
+      end
+    end
+    @vframe.create; @vframe.show; @vframe.recalc
+  end
+
+  # Create and show this window
+  def create
+    super
+    show(PLACEMENT_SCREEN)
+  end
+end
+
+if __FILE__ == $0
+  application = Fox::FXApp.new("ThreadApp", "FoxTest")
+  ThreadedWindow.new(application)
+  application.create
+  application.run
+end