OK. Finally I figure out the workaround, I need to manually run the following command before clicking on the build all button.

Qt Code: 
  1. moc qttreepropertybrowser > qttreepropertybrowser.moc
  2. moc qtpropertymanager > qtpropertymanager.moc
  3. moc qteditorfactory > qteditorfactory.moc
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Not sure why. QT people should include these command in their build file