FlutterのshowDialogのAlertDialogサンプル

• Android、iOS用でそれぞれ環境に合うDialogを出力する

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

class CommonDialogView {
  static Future<T?> show<T extends Object>(BuildContext context, String text) {
    return Platform.isIOS
        ? _showCupertinoDialog<T>(context, text)
        : _showMaterialDialog<T>(context, text);
  }

  static Future<T?> _showCupertinoDialog<T extends Object>(
      BuildContext context, String text) {
    return showCupertinoDialog<T>(
      context: context,
      builder: (BuildContext context) {
        return CupertinoAlertDialog(
          content: _buildContent(text),
          actions: _buildCupertinoActions(context),
        );
      },
    );
  }

  static Future<T?> _showMaterialDialog<T extends Object>(
      BuildContext context, String text) {
    return showDialog<T>(
      context: context,
      builder: (BuildContext context) {
        return AlertDialog(
          content: _buildContent(text),
          actions: _buildMaterialActions(context),
        );
      },
    );
  }

  static Widget _buildContent(String text) {
    return SingleChildScrollView(
      child: Center(
        child: Text(
          text,
          style: const TextStyle(fontSize: 16),
        ),
      ),
    );
  }

  static List<Widget> _buildMaterialActions(BuildContext context) {
    return <Widget>[
      TextButton(
        onPressed: () => Navigator.pop(context, 'Cancel'),
        child: const Text('キャンセル'),
      ),
      TextButton(
        onPressed: () => Navigator.of(context).pop(),
        child: const Text('OK'),
      ),
    ];
  }

  static List<Widget> _buildCupertinoActions(BuildContext context) {
    return <Widget>[
      CupertinoDialogAction(
        onPressed: () => Navigator.pop(context, 'Cancel'),
        child: const Text('キャンセル'),
      ),
      CupertinoDialogAction(
        onPressed: () => Navigator.of(context).pop(),
        child: const Text('OK'),
      ),
    ];
  }
}

    // 使用例
    CommonDialogView.show(context,"コンテンツのtext")