title: how to stop paint while adding controls?
body: <p>sometimes i get this exception when clearing and re-adding controls to a container</p>
  
  <p>I think it related to paint issue ,is there a way I can stop drawing events till I finish adding controls </p>
  
  <pre><code>03-10 14:00:36.435: W/System.err(13405):    at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
  03-10 14:00:36.435: W/System.err(13405):    at java.util.ArrayList.get(ArrayList.java:308)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.i.a(Container.java:1312)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.h.b(Component.java:1308)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.h.d(Component.java:1282)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.h.a(Component.java:1257)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.i.a(Container.java:1313)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.h.b(Component.java:1302)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.h.d(Component.java:1282)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.h.a(Component.java:1257)
  03-10 14:00:36.435: W/System.err(13405):    at com.codename1.m.i.a(Container.java:1313)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.b(Component.java:1308)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.d(Component.java:1282)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.a(Component.java:1257)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.i.a(Container.java:1313)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.b(Component.java:1308)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.d(Component.java:1282)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.a(Component.java:1257)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.i.a(Container.java:1313)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.p.a(Form.java:3099)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.b(Component.java:1308)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.p.b(Form.java:3109)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.d(Component.java:1282)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.a(Component.java:1257)
  03-10 14:00:36.445: W/System.err(13405):    at com.codename1.m.h.d(Component.java:1225)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.m.h.c(Component.java:1510)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.m.h.i(Component.java:1457)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.impl.a.p(CodenameOneImplementation.java:516)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.m.l.j(Display.java:1071)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.m.l.i(Display.java:993)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.m.ab.run(RunnableWrapper.java:120)
  03-10 14:00:36.455: W/System.err(13405):    at com.codename1.impl.b$1.run(CodenameOneThread.java:60)
  03-10 14:00:36.455: W/System.err(13405):    at java.lang.Thread.run(Thread.java:841)
  </code></pre>