The monitoring function is triggered twice under the same Url

System info

Issue occurs on: Android Plugin version: 0.3.11 Flutter doctor output: [✓] Flutter (Channel stable, 1.22.5, on Mac OS X 10.15.3 19D76 darwin-x64, locale zh-Hans-CN)

[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.3) [✓] Xcode - develop for iOS and macOS (Xcode 11.5) [✓] Android Studio (version 3.5) [✓] IntelliJ IDEA Ultimate Edition (version 2019.3) [✓] VS Code (version 1.52.1) [✓] Connected device (1 available)

• No issues found!

paste it here...

Steps to Reproduce

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@override
void initState() {
super.initState();
webviewPlugin.onUrlChanged.listen((url) {
  // TODO:相同的地址会执行两次，bug
  if (mounted) {
    print("url changed: $url");
    isLoading = false;
    setState(() {});
    if (url != null && url.contains("code=")) {
      String code = url.split("?")[1].split("=")[1].split("&")[0];
      Map<String, dynamic> params = Map();
      params["client_id"] = AppApiConfig.CLIENT_ID;
      params["client_secret"] = AppApiConfig.SECRET_KEY;
      params["grant_type"] = "authorization_code";
      params["redirect_uri"] = AppApiConfig.CALLBACK;
      params["code"] = '$code';
      params["dataType"] = "json";
      NetUtils.post(AppUrls.OAUTH2_TOKEN, params).then((data) async {
        Map<String, dynamic> map = json.decode(data);
        // TODO: 处理bug错误
        if (map["error"] == "400") {
          print("请求出错");
          return;
        }
        if (map != null && map.isNotEmpty) {
          await DataUtils.setLoginInfo(map: map);
          Navigator.pop(context, AppMsg.SUCCESS);
        }
      });
    }
  }
});
}

2. ...
3. ...

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2 I/flutter (12981): url changed: http://blog.jackson615.top/?code=7rX7S6&state=


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fluttercommunity / flutter_webview_plugin

The monitoring function is triggered twice under the same Url #862

System info

Steps to Reproduce