SpinKitPulsingGrid constructor
      const
      SpinKitPulsingGrid({ 
    
    
- Key? key,
 - Color? color,
 - double size = 50.0,
 - IndexedWidgetBuilder? itemBuilder,
 - Duration duration = const Duration(milliseconds: 1500),
 - BoxShape? boxShape,
 - AnimationController? controller,
 
Implementation
const SpinKitPulsingGrid({
  Key? key,
  this.color,
  this.size = 50.0,
  this.itemBuilder,
  this.duration = const Duration(milliseconds: 1500),
  this.boxShape,
  this.controller,
})  : assert(
        !(itemBuilder is IndexedWidgetBuilder && color is Color) && !(itemBuilder == null && color == null),
        'You should specify either a itemBuilder or a color',
      ),
      super(key: key);