ExpansionPanelList({Key key, List<ExpansionPanel> children: const [], ExpansionPanelCallback expansionCallback, Duration animationDuration: kThemeAnimationDuration })

Creates an expansion panel list widget. The expansionCallback is triggered when an expansion panel expand/collapse button is pushed.

Source 

ExpansionPanelList({
  Key key,
  this.children: const <ExpansionPanel>[],
  this.expansionCallback,
  this.animationDuration: kThemeAnimationDuration
}) : super(key: key) {
  assert(this.children != null);
  assert(this.animationDuration != null);
}