---

SwiftUI选择器选择参数给出 “表达式类型 'binding <_>' 不明确，没有更多上下文” 错误

我得到一个表达式类型 'binding <_>' 是不明确的，没有更多的上下文错误在 $ order.quantity.contracts在下面的代码:
Struct ContractsPickerView: View {
@ 绑定var顺序:

.htaccess .net .net-core 2d 3d 3d-printing abstract-syntax-tree actions-on-google actionscript-3 activemq acumatica adobe-xd aframe ag-grid air airflow ajax akka alert alexa algorithm alignment allure amadeus amazon-cognito amazon-deequ amazon-dynamodb amazon-ec2 amazon-redshift amazon-s3 amazon-sqs amazon-web-services amcharts amcharts4 amp-html anaconda android android-activity android-fragments android-jetpack-compose android-layout android-management-api android-ndk android-studio android-x86 android-youtube-api angular angular-cli angular-cli-v6 angular-material angular-material2 angular5 angularjs animation annotations ansible ant antd antlr antlr4 anylogic anypoint-studio apache apache-camel apache-commons-dbcp apache-drill apache-flex apache-flink apache-kafka apache-kafka-connect apache-nifi apache-spark apache-superset apache2 apex apex-code api appdelegate apple-sign-in applepay applescript architecture arduino arkit arm arrays artifactory artificial-intelligence asp-classic asp.net asp.net-core asp.net-core-mvc asp.net-identity asp.net-mvc asp.net-mvc-3 asp.net-mvc-4 asp.net-web-api assembly asynchronous atlassian-sourcetree audio authentication autocomplete autodesk-forge automated-tests automation automator avro awk aws-documentdb aws-kms aws-lambda aws-xray axapta axis azure azure-active-directory azure-ad-b2c azure-cosmosdb