Added CupertinoButton alignment property - #73900

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';

class Home extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      child: Center(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: <Widget>[
            SizedBox(
              width: 300,
              child: CupertinoButton.filled(
                alignment: Alignment.center,
                padding: EdgeInsets.all(16),
                onPressed: () { },
                child: Text('center'),
              ),
            ),
            SizedBox(height: 16),
            SizedBox(
              width: 300,
              child: CupertinoButton.filled(
                alignment: Alignment.centerRight,
                padding: EdgeInsets.all(16),
                onPressed: () { },
                child: Text('centerRight'),
              ),
            ),
            SizedBox(height: 16),
            SizedBox(
              width: 300,
              child: CupertinoButton.filled(
                alignment: Alignment.centerLeft,
                padding: EdgeInsets.all(16),
                onPressed: () { },
                child: Text('centerLeft'),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

void main() {
  runApp(CupertinoApp(home: Home()));
}