FadeInDown constructor
      
      FadeInDown({})
     
    
    
Implementation
FadeInDown(
    {key,
    required this.child,
    this.duration = const Duration(milliseconds: 800),
    this.delay = const Duration(milliseconds: 0),
    this.controller,
    this.manualTrigger = false,
    this.animate = true,
    this.from = 100})
    : super(key: key) {
  if (manualTrigger == true && controller == null) {
    throw FlutterError('If you want to use manualTrigger:true, \n\n'
        'Then you must provide the controller property, that is a callback like:\n\n'
        ' ( controller: AnimationController) => yourController = controller \n\n');
  }
}