Normally if you place three the same size icons in a stack, they will stands on top of each other, then we can use ‘Align‘ and ‘Position‘ to positioning them:
class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( home: Scaffold( body: SizedBox.expand( child: Stack( children: <Widget>[ Icon( Icons.camera, size: 100, color: Colors.red, ), Align( alignment: Alignment.center, child: Icon( Icons.camera, size: 100, color: Colors.blue, )), Positioned( bottom: 20, child: Icon( Icons.camera, size: 100, color: Colors.green, )) ], ), ), ), ); } }
原文：https://www.cnblogs.com/Answer1215/p/11312818.html