Firebase Dynamic Links在iOS端崩溃，Android端正常运行求助

代码在Android设备上可正常生成短动态链接，但iOS设备执行时抛出类型转换错误：type 'int' is not a subtype of type 'String' in type cast。

原代码 #

String userId = uid;
final DynamicLinkParameters dynamicLinkParameters = DynamicLinkParameters(
    uriPrefix: 'https://mywebsite.com/user/',
    link: Uri.parse(
      'https://mywebsite.com/link/?username=$userId',
    ),
  );

final ShortDynamicLink shortDynamicLink = await dynamicLink.buildShortLink(
  dynamicLinkParameters,
  shortLinkType: ShortDynamicLinkType.short,
);

报错日志 #

flutter: type 'int' is not a subtype of type 'String' in type cast
2022-07-29 22:30:23.235625+0300 Runner[51971:280704] flutter: 
#0 new LinkedHashMap.from.<anonymous closure> (dart:collection/linked_hash_map.dart:187:26)
#1 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:614:13)
#2 new LinkedHashMap.from (dart:collection/linked_hash_map.dart:186:11)
#3 platformExceptionToFirebaseException  (package:firebase_dynamic_links_platform_interface/src/method_channel/utils/exception.dart:32:9)
#4 convertPlatformException  (package:firebase_dynamic_links_platform_interface/src/method_channel/utils/exception.dart:17:5)
#5 MethodChannelFirebaseDynamicLinks.buildShortLink (package:firebase_dynamic_links_platform_interface/src/method_channel/method_channel_firebase_dynamic_links.dart:196:7)

解决方案 #

问题根源是uid实际为int类型，Android端会自动隐式转为字符串，但iOS端的Method Channel在传递参数时会严格保留类型，导致URL拼接后参数类型不匹配引发错误。

修改方式：强制将uid转为字符串类型，确保URL参数为纯字符串：

// 方式1：先将uid转为字符串再赋值
String userId = uid.toString();
final DynamicLinkParameters dynamicLinkParameters = DynamicLinkParameters(
    uriPrefix: 'https://mywebsite.com/user/',
    link: Uri.parse(
      'https://mywebsite.com/link/?username=$userId',
    ),
  );

final ShortDynamicLink shortDynamicLink = await dynamicLink.buildShortLink(
  dynamicLinkParameters,
  shortLinkType: ShortDynamicLinkType.short,
);

或者直接在URL拼接时转换：

final DynamicLinkParameters dynamicLinkParameters = DynamicLinkParameters(
    uriPrefix: 'https://mywebsite.com/user/',
    link: Uri.parse(
      'https://mywebsite.com/link/?username=${uid.toString()}',
    ),
  );

final ShortDynamicLink shortDynamicLink = await dynamicLink.buildShortLink(
  dynamicLinkParameters,
  shortLinkType: ShortDynamicLinkType.short,
);

内容的提问来源于stack exchange，提问作者Emma Alden