Flutter:如何在测试中访问/检查小部件的属性？

Question

我想测试一些小部件的属性，但我没有找到一种简单的方法。

这是一个带有密码字段的简单示例，我如何检查 blurText 是否设置为 true ？

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

const darkBlue = Color.fromARGB(255, 18, 32, 47);

Future<void> main() async {
  testWidgets('Wheelio logo appear on the login screen',
      (WidgetTester tester) async {
    final Key _formKey = GlobalKey<FormState>();
    final TextEditingController passwordController = TextEditingController();
    const Key _passwordKey = Key('PASSWORD_KEY');
    final Finder passwordField = find.byKey(_passwordKey);
    await tester.pumpWidget(MaterialApp(
      theme: ThemeData.dark().copyWith(scaffoldBackgroundColor: darkBlue),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(
          child: Form(
            key: _formKey,
            child: TextFormField(
              key: _passwordKey,
              obscureText: true,
              controller: passwordController,
            ),
          ),
        ),
      ),
    ));

    await tester.pump();
    expect(passwordField, findsOneWidget);
    final TextFormField myPasswordWidget =
        tester.widget(passwordField) as TextFormField;

    //    How can I check that obscureText property is set to true ?
  });
}

Answer 1

您可以使用 tester和 find获取小部件树中的任何内容。

例如，如果你想测试一个 Text有房产textAlign设置为 TextAlign.center ， 你可以做:

expect(
  tester.widget(find.byType(Text)),
  isA<Text>().having((t) => t.textAlign, 'textAlign', TextAlign.center),
);