Flutter构建失败：razorpay_flutter与paytm_allinonesdk中Registrar未找到

错误信息 #

error: cannot find symbol
import io.flutter.plugin.common.PluginRegistry.Registrar;
                                              ^
symbol:   class Registrar
location: interface PluginRegistry

public static void registerWith(Registrar registrar) {
                            ^
symbol:   class Registrar
location: class RazorpayFlutterPlugin

复现步骤 #

• 在pubspec.yaml中添加razorpay_flutter: ^1.3.7和paytm_allinonesdk: ^1.2.8
• 执行flutter pub get
• 执行flutter build apk触发错误

问题原因 #

Flutter 3.20及以上版本移除了PluginRegistry.Registrar接口，改用FlutterPlugin接口实现插件注册。你使用的旧版本支付插件仍依赖废弃的Registrar，导致编译失败。

解决方案 #

方案1：升级插件到兼容版本 #

将插件版本更新为适配Flutter 3.20+的最新稳定版，示例pubspec.yaml配置：

dependencies:
  razorpay_flutter: ^2.3.0
  paytm_allinonesdk: ^1.5.0

执行flutter clean && flutter pub get后重新构建项目。

方案2：手动修改插件代码适配新接口 #

如果无法升级插件，可手动修改插件的Android端代码：

1. 找到插件的Android实现文件（如razorpay_flutter的RazorpayFlutterPlugin.java，路径通常为android/src/main/java/com/razorpay/flutter/）
2. 替换原有代码为适配FlutterPlugin的实现：

   import io.flutter.embedding.engine.plugins.FlutterPlugin;
   import io.flutter.plugin.common.MethodCall;
   import io.flutter.plugin.common.MethodChannel;
   import io.flutter.plugin.common.MethodChannel.MethodCallHandler;
   import io.flutter.plugin.common.MethodChannel.Result;
   import io.flutter.embedding.engine.plugins.FlutterPlugin.FlutterPluginBinding;
   
   public class RazorpayFlutterPlugin implements FlutterPlugin, MethodCallHandler {
     private MethodChannel channel;
   
     @Override
     public void onAttachedToEngine(FlutterPluginBinding flutterPluginBinding) {
       channel = new MethodChannel(flutterPluginBinding.getBinaryMessenger(), "razorpay_flutter");
       channel.setMethodCallHandler(this);
     }
   
     @Override
     public void onMethodCall(MethodCall call, Result result) {
       // 保留原有业务逻辑
     }
   
     @Override
     public void onDetachedFromEngine(FlutterPluginBinding binding) {
       channel.setMethodCallHandler(null);
     }
   }
   

3. 对paytm_allinonesdk的对应文件执行相同修改
4. 执行flutter clean && flutter pub get && flutter build apk

内容的提问来源于stack exchange，提问作者Hammad Khan