diplomatic-quarter/lib/pages/conference/widgets/platform_alert_dialog.dart

import 'dart:io';

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

import './platform_widget.dart';

class PlatformAlertDialog extends PlatformWidget {
  PlatformAlertDialog({@required this.title, @required this.content, @required this.defaultActionText, this.cancelActionText})
      : assert(title != null),
        assert(content != null),
        assert(defaultActionText != null);

  final String title;
  final String content;
  final String defaultActionText;
  final String cancelActionText;

  Future<bool> show(BuildContext context) async {
    return Platform.isIOS
        ? await showCupertinoDialog<bool>(
            context: context,
            builder: (BuildContext context) => this,
          )
        : await showDialog<bool>(
            context: context,
            barrierDismissible: false,
            builder: (BuildContext context) => this,
          );
  }

  @override
  Widget buildCupertinoWidget(BuildContext context) {
    return CupertinoAlertDialog(
      title: Text(title),
      content: Text(content),
      actions: _buildActions(context),
    );
  }

  @override
  Widget buildMaterialWidget(BuildContext context) {
    return AlertDialog(
      title: Text(title),
      content: Text(content),
      actions: _buildActions(context),
    );
  }

  List<Widget> _buildActions(BuildContext context) {
    final actions = <Widget>[];
    if (cancelActionText != null) {
      actions.add(
        PlatformAlertDialogAction(
          child: Text(cancelActionText),
          onPressed: () {
            Navigator.of(context).pop(false);
          },
        ),
      );
    }
    actions.add(
      PlatformAlertDialogAction(
        child: Text(defaultActionText),
        onPressed: () {
          Navigator.of(context).pop(true);
        },
      ),
    );
    return actions;
  }
}

class PlatformAlertDialogAction extends PlatformWidget {
  PlatformAlertDialogAction({
    this.child,
    this.onPressed,
  });

  final Widget child;
  final VoidCallback onPressed;

  @override
  Widget buildCupertinoWidget(BuildContext context) {
    return CupertinoDialogAction(
      child: child,
      onPressed: onPressed,
    );
  }

  @override
  Widget buildMaterialWidget(BuildContext context) {
    return FlatButton(
      child: child,
      onPressed: onPressed,
    );
  }
}