native ffigen has an unknown type name error [Semantic Issue] when generating swift binding.

I have written a swift class in a plugin like this

//
//  PreviewView.swift
//  camerax_ios
//
//  Created by 闫守旺 on 2024/7/9.
//

import AVFoundation
import Flutter

@objc public class PreviewView: UIView, FlutterPlatformView {
    // Use a capture video preview layer as the view's backing layer.
    public override class var layerClass: AnyClass {
        AVCaptureVideoPreviewLayer.self
    }
    
    @objc public var previewLayer: AVCaptureVideoPreviewLayer {
        layer as! AVCaptureVideoPreviewLayer
    }
    
    // Connect the layer to a capture session.
    @objc public var session: AVCaptureSession? {
        get { previewLayer.session }
        set { previewLayer.session = newValue }
    }
    
    @objc public var videoGravity: AVLayerVideoGravity {
        get { previewLayer.videoGravity }
        set { previewLayer.videoGravity = newValue }
    }
    
    public override func removeFromSuperview() {
        guard let view = PreviewViewFactory.shared.views.first(where: { $0.value == self }) else {
            return
        }
        PreviewViewFactory.shared.views.removeValue(forKey: view.key)
    }
    
    public func view() -> UIView {
        return self
    }
}

I can find the objc header in example/build/ios/Debug-iphonesimulator/camerax_ios/camerax_ios.framework/Headers/camerax_ios-Swift.h

#if 0
#elif defined(__arm64__) && __arm64__
// Generated by Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
#ifndef CAMERAX_IOS_SWIFT_H
#define CAMERAX_IOS_SWIFT_H
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wgcc-compat"

#if !defined(__has_include)
# define __has_include(x) 0
#endif
#if !defined(__has_attribute)
# define __has_attribute(x) 0
#endif
#if !defined(__has_feature)
# define __has_feature(x) 0
#endif
#if !defined(__has_warning)
# define __has_warning(x) 0
#endif

#if __has_include(<swift/objc-prologue.h>)
# include <swift/objc-prologue.h>
#endif

#pragma clang diagnostic ignored "-Wauto-import"
#if defined(__OBJC__)
#include <Foundation/Foundation.h>
#endif
#if defined(__cplusplus)
#include <cstdint>
#include <cstddef>
#include <cstdbool>
#include <cstring>
#include <stdlib.h>
#include <new>
#include <type_traits>
#else
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#include <string.h>
#endif
#if defined(__cplusplus)
#if defined(__arm64e__) && __has_include(<ptrauth.h>)
# include <ptrauth.h>
#else
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wreserved-macro-identifier"
# ifndef __ptrauth_swift_value_witness_function_pointer
#  define __ptrauth_swift_value_witness_function_pointer(x)
# endif
# ifndef __ptrauth_swift_class_method_pointer
#  define __ptrauth_swift_class_method_pointer(x)
# endif
#pragma clang diagnostic pop
#endif
#endif

#if !defined(SWIFT_TYPEDEFS)
# define SWIFT_TYPEDEFS 1
# if __has_include(<uchar.h>)
#  include <uchar.h>
# elif !defined(__cplusplus)
typedef uint_least16_t char16_t;
typedef uint_least32_t char32_t;
# endif
typedef float swift_float2  __attribute__((__ext_vector_type__(2)));
typedef float swift_float3  __attribute__((__ext_vector_type__(3)));
typedef float swift_float4  __attribute__((__ext_vector_type__(4)));
typedef double swift_double2  __attribute__((__ext_vector_type__(2)));
typedef double swift_double3  __attribute__((__ext_vector_type__(3)));
typedef double swift_double4  __attribute__((__ext_vector_type__(4)));
typedef int swift_int2  __attribute__((__ext_vector_type__(2)));
typedef int swift_int3  __attribute__((__ext_vector_type__(3)));
typedef int swift_int4  __attribute__((__ext_vector_type__(4)));
typedef unsigned int swift_uint2  __attribute__((__ext_vector_type__(2)));
typedef unsigned int swift_uint3  __attribute__((__ext_vector_type__(3)));
typedef unsigned int swift_uint4  __attribute__((__ext_vector_type__(4)));
#endif

#if !defined(SWIFT_PASTE)
# define SWIFT_PASTE_HELPER(x, y) x##y
# define SWIFT_PASTE(x, y) SWIFT_PASTE_HELPER(x, y)
#endif
#if !defined(SWIFT_METATYPE)
# define SWIFT_METATYPE(X) Class
#endif
#if !defined(SWIFT_CLASS_PROPERTY)
# if __has_feature(objc_class_property)
#  define SWIFT_CLASS_PROPERTY(...) __VA_ARGS__
# else
#  define SWIFT_CLASS_PROPERTY(...) 
# endif
#endif
#if !defined(SWIFT_RUNTIME_NAME)
# if __has_attribute(objc_runtime_name)
#  define SWIFT_RUNTIME_NAME(X) __attribute__((objc_runtime_name(X)))
# else
#  define SWIFT_RUNTIME_NAME(X) 
# endif
#endif
#if !defined(SWIFT_COMPILE_NAME)
# if __has_attribute(swift_name)
#  define SWIFT_COMPILE_NAME(X) __attribute__((swift_name(X)))
# else
#  define SWIFT_COMPILE_NAME(X) 
# endif
#endif
#if !defined(SWIFT_METHOD_FAMILY)
# if __has_attribute(objc_method_family)
#  define SWIFT_METHOD_FAMILY(X) __attribute__((objc_method_family(X)))
# else
#  define SWIFT_METHOD_FAMILY(X) 
# endif
#endif
#if !defined(SWIFT_NOESCAPE)
# if __has_attribute(noescape)
#  define SWIFT_NOESCAPE __attribute__((noescape))
# else
#  define SWIFT_NOESCAPE 
# endif
#endif
#if !defined(SWIFT_RELEASES_ARGUMENT)
# if __has_attribute(ns_consumed)
#  define SWIFT_RELEASES_ARGUMENT __attribute__((ns_consumed))
# else
#  define SWIFT_RELEASES_ARGUMENT 
# endif
#endif
#if !defined(SWIFT_WARN_UNUSED_RESULT)
# if __has_attribute(warn_unused_result)
#  define SWIFT_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
# else
#  define SWIFT_WARN_UNUSED_RESULT 
# endif
#endif
#if !defined(SWIFT_NORETURN)
# if __has_attribute(noreturn)
#  define SWIFT_NORETURN __attribute__((noreturn))
# else
#  define SWIFT_NORETURN 
# endif
#endif
#if !defined(SWIFT_CLASS_EXTRA)
# define SWIFT_CLASS_EXTRA 
#endif
#if !defined(SWIFT_PROTOCOL_EXTRA)
# define SWIFT_PROTOCOL_EXTRA 
#endif
#if !defined(SWIFT_ENUM_EXTRA)
# define SWIFT_ENUM_EXTRA 
#endif
#if !defined(SWIFT_CLASS)
# if __has_attribute(objc_subclassing_restricted)
#  define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) __attribute__((objc_subclassing_restricted)) SWIFT_CLASS_EXTRA
#  define SWIFT_CLASS_NAMED(SWIFT_NAME) __attribute__((objc_subclassing_restricted)) SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
# else
#  define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
#  define SWIFT_CLASS_NAMED(SWIFT_NAME) SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
# endif
#endif
#if !defined(SWIFT_RESILIENT_CLASS)
# if __has_attribute(objc_class_stub)
#  define SWIFT_RESILIENT_CLASS(SWIFT_NAME) SWIFT_CLASS(SWIFT_NAME) __attribute__((objc_class_stub))
#  define SWIFT_RESILIENT_CLASS_NAMED(SWIFT_NAME) __attribute__((objc_class_stub)) SWIFT_CLASS_NAMED(SWIFT_NAME)
# else
#  define SWIFT_RESILIENT_CLASS(SWIFT_NAME) SWIFT_CLASS(SWIFT_NAME)
#  define SWIFT_RESILIENT_CLASS_NAMED(SWIFT_NAME) SWIFT_CLASS_NAMED(SWIFT_NAME)
# endif
#endif
#if !defined(SWIFT_PROTOCOL)
# define SWIFT_PROTOCOL(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_PROTOCOL_EXTRA
# define SWIFT_PROTOCOL_NAMED(SWIFT_NAME) SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_PROTOCOL_EXTRA
#endif
#if !defined(SWIFT_EXTENSION)
# define SWIFT_EXTENSION(M) SWIFT_PASTE(M##_Swift_, __LINE__)
#endif
#if !defined(OBJC_DESIGNATED_INITIALIZER)
# if __has_attribute(objc_designated_initializer)
#  define OBJC_DESIGNATED_INITIALIZER __attribute__((objc_designated_initializer))
# else
#  define OBJC_DESIGNATED_INITIALIZER 
# endif
#endif
#if !defined(SWIFT_ENUM_ATTR)
# if __has_attribute(enum_extensibility)
#  define SWIFT_ENUM_ATTR(_extensibility) __attribute__((enum_extensibility(_extensibility)))
# else
#  define SWIFT_ENUM_ATTR(_extensibility) 
# endif
#endif
#if !defined(SWIFT_ENUM)
# define SWIFT_ENUM(_type, _name, _extensibility) enum _name : _type _name; enum SWIFT_ENUM_ATTR(_extensibility) SWIFT_ENUM_EXTRA _name : _type
# if __has_feature(generalized_swift_name)
#  define SWIFT_ENUM_NAMED(_type, _name, SWIFT_NAME, _extensibility) enum _name : _type _name SWIFT_COMPILE_NAME(SWIFT_NAME); enum SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_ENUM_ATTR(_extensibility) SWIFT_ENUM_EXTRA _name : _type
# else
#  define SWIFT_ENUM_NAMED(_type, _name, SWIFT_NAME, _extensibility) SWIFT_ENUM(_type, _name, _extensibility)
# endif
#endif
#if !defined(SWIFT_UNAVAILABLE)
# define SWIFT_UNAVAILABLE __attribute__((unavailable))
#endif
#if !defined(SWIFT_UNAVAILABLE_MSG)
# define SWIFT_UNAVAILABLE_MSG(msg) __attribute__((unavailable(msg)))
#endif
#if !defined(SWIFT_AVAILABILITY)
# define SWIFT_AVAILABILITY(plat, ...) __attribute__((availability(plat, __VA_ARGS__)))
#endif
#if !defined(SWIFT_WEAK_IMPORT)
# define SWIFT_WEAK_IMPORT __attribute__((weak_import))
#endif
#if !defined(SWIFT_DEPRECATED)
# define SWIFT_DEPRECATED __attribute__((deprecated))
#endif
#if !defined(SWIFT_DEPRECATED_MSG)
# define SWIFT_DEPRECATED_MSG(...) __attribute__((deprecated(__VA_ARGS__)))
#endif
#if !defined(SWIFT_DEPRECATED_OBJC)
# if __has_feature(attribute_diagnose_if_objc)
#  define SWIFT_DEPRECATED_OBJC(Msg) __attribute__((diagnose_if(1, Msg, "warning")))
# else
#  define SWIFT_DEPRECATED_OBJC(Msg) SWIFT_DEPRECATED_MSG(Msg)
# endif
#endif
#if defined(__OBJC__)
#if !defined(IBSegueAction)
# define IBSegueAction 
#endif
#endif
#if !defined(SWIFT_EXTERN)
# if defined(__cplusplus)
#  define SWIFT_EXTERN extern "C"
# else
#  define SWIFT_EXTERN extern
# endif
#endif
#if !defined(SWIFT_CALL)
# define SWIFT_CALL __attribute__((swiftcall))
#endif
#if !defined(SWIFT_INDIRECT_RESULT)
# define SWIFT_INDIRECT_RESULT __attribute__((swift_indirect_result))
#endif
#if !defined(SWIFT_CONTEXT)
# define SWIFT_CONTEXT __attribute__((swift_context))
#endif
#if !defined(SWIFT_ERROR_RESULT)
# define SWIFT_ERROR_RESULT __attribute__((swift_error_result))
#endif
#if defined(__cplusplus)
# define SWIFT_NOEXCEPT noexcept
#else
# define SWIFT_NOEXCEPT 
#endif
#if !defined(SWIFT_C_INLINE_THUNK)
# if __has_attribute(always_inline)
# if __has_attribute(nodebug)
#  define SWIFT_C_INLINE_THUNK inline __attribute__((always_inline)) __attribute__((nodebug))
# else
#  define SWIFT_C_INLINE_THUNK inline __attribute__((always_inline))
# endif
# else
#  define SWIFT_C_INLINE_THUNK inline
# endif
#endif
#if defined(_WIN32)
#if !defined(SWIFT_IMPORT_STDLIB_SYMBOL)
# define SWIFT_IMPORT_STDLIB_SYMBOL __declspec(dllimport)
#endif
#else
#if !defined(SWIFT_IMPORT_STDLIB_SYMBOL)
# define SWIFT_IMPORT_STDLIB_SYMBOL 
#endif
#endif
#if defined(__OBJC__)
#if __has_feature(objc_modules)
#if __has_warning("-Watimport-in-framework-header")
#pragma clang diagnostic ignored "-Watimport-in-framework-header"
#endif
@import AVFoundation;
@import CoreFoundation;
@import Flutter;
@import ObjectiveC;
@import UIKit;
#endif

#endif
#pragma clang diagnostic ignored "-Wproperty-attribute-mismatch"
#pragma clang diagnostic ignored "-Wduplicate-method-arg"
#if __has_warning("-Wpragma-clang-attribute")
# pragma clang diagnostic ignored "-Wpragma-clang-attribute"
#endif
#pragma clang diagnostic ignored "-Wunknown-pragmas"
#pragma clang diagnostic ignored "-Wnullability"
#pragma clang diagnostic ignored "-Wdollar-in-identifier-extension"

#if __has_attribute(external_source_symbol)
# pragma push_macro("any")
# undef any
# pragma clang attribute push(__attribute__((external_source_symbol(language="Swift", defined_in="camerax_ios",generated_declaration))), apply_to=any(function,enum,objc_interface,objc_category,objc_protocol))
# pragma pop_macro("any")
#endif

#if defined(__OBJC__)
@protocol FlutterPluginRegistrar;

SWIFT_CLASS("_TtC11camerax_ios16CameraXiOSPlugin")
@interface CameraXiOSPlugin : NSObject <FlutterPlugin>
+ (void)registerWithRegistrar:(id <FlutterPluginRegistrar> _Nonnull)registrar;
- (nonnull instancetype)init OBJC_DESIGNATED_INITIALIZER;
@end

@class AVCaptureVideoPreviewLayer;
@class AVCaptureSession;
@class NSCoder;

SWIFT_CLASS("_TtC11camerax_ios11PreviewView")
@interface PreviewView : UIView <FlutterPlatformView>
SWIFT_CLASS_PROPERTY(@property (nonatomic, class, readonly) Class _Nonnull layerClass;)
+ (Class _Nonnull)layerClass SWIFT_WARN_UNUSED_RESULT;
@property (nonatomic, readonly, strong) AVCaptureVideoPreviewLayer * _Nonnull previewLayer;
@property (nonatomic, strong) AVCaptureSession * _Nullable session;
@property (nonatomic) AVLayerVideoGravity _Nonnull videoGravity;
- (void)removeFromSuperview;
- (UIView * _Nonnull)view SWIFT_WARN_UNUSED_RESULT;
- (nonnull instancetype)initWithFrame:(CGRect)frame OBJC_DESIGNATED_INITIALIZER;
- (nullable instancetype)initWithCoder:(NSCoder * _Nonnull)coder OBJC_DESIGNATED_INITIALIZER;
@end


SWIFT_CLASS("_TtC11camerax_ios18PreviewViewFactory")
@interface PreviewViewFactory : NSObject <FlutterPlatformViewFactory>
SWIFT_CLASS_PROPERTY(@property (nonatomic, class, readonly, strong) PreviewViewFactory * _Nonnull shared;)
+ (PreviewViewFactory * _Nonnull)shared SWIFT_WARN_UNUSED_RESULT;
- (nonnull instancetype)init SWIFT_UNAVAILABLE;
+ (nonnull instancetype)new SWIFT_UNAVAILABLE_MSG("-init is unavailable");
- (id <FlutterPlatformView> _Nonnull)createWithFrame:(CGRect)frame viewIdentifier:(int64_t)viewId arguments:(id _Nullable)args SWIFT_WARN_UNUSED_RESULT;
- (PreviewView * _Nullable)retrieveView:(int64_t)viewId SWIFT_WARN_UNUSED_RESULT;
@end

#endif
#if __has_attribute(external_source_symbol)
# pragma clang attribute pop
#endif
#if defined(__cplusplus)
#endif
#pragma clang diagnostic pop
#endif

#elif defined(__x86_64__) && __x86_64__
// Generated by Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
#ifndef CAMERAX_IOS_SWIFT_H
#define CAMERAX_IOS_SWIFT_H
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wgcc-compat"

#if !defined(__has_include)
# define __has_include(x) 0
#endif
#if !defined(__has_attribute)
# define __has_attribute(x) 0
#endif
#if !defined(__has_feature)
# define __has_feature(x) 0
#endif
#if !defined(__has_warning)
# define __has_warning(x) 0
#endif

#if __has_include(<swift/objc-prologue.h>)
# include <swift/objc-prologue.h>
#endif

#pragma clang diagnostic ignored "-Wauto-import"
#if defined(__OBJC__)
#include <Foundation/Foundation.h>
#endif
#if defined(__cplusplus)
#include <cstdint>
#include <cstddef>
#include <cstdbool>
#include <cstring>
#include <stdlib.h>
#include <new>
#include <type_traits>
#else
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#include <string.h>
#endif
#if defined(__cplusplus)
#if defined(__arm64e__) && __has_include(<ptrauth.h>)
# include <ptrauth.h>
#else
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wreserved-macro-identifier"
# ifndef __ptrauth_swift_value_witness_function_pointer
#  define __ptrauth_swift_value_witness_function_pointer(x)
# endif
# ifndef __ptrauth_swift_class_method_pointer
#  define __ptrauth_swift_class_method_pointer(x)
# endif
#pragma clang diagnostic pop
#endif
#endif

#if !defined(SWIFT_TYPEDEFS)
# define SWIFT_TYPEDEFS 1
# if __has_include(<uchar.h>)
#  include <uchar.h>
# elif !defined(__cplusplus)
typedef uint_least16_t char16_t;
typedef uint_least32_t char32_t;
# endif
typedef float swift_float2  __attribute__((__ext_vector_type__(2)));
typedef float swift_float3  __attribute__((__ext_vector_type__(3)));
typedef float swift_float4  __attribute__((__ext_vector_type__(4)));
typedef double swift_double2  __attribute__((__ext_vector_type__(2)));
typedef double swift_double3  __attribute__((__ext_vector_type__(3)));
typedef double swift_double4  __attribute__((__ext_vector_type__(4)));
typedef int swift_int2  __attribute__((__ext_vector_type__(2)));
typedef int swift_int3  __attribute__((__ext_vector_type__(3)));
typedef int swift_int4  __attribute__((__ext_vector_type__(4)));
typedef unsigned int swift_uint2  __attribute__((__ext_vector_type__(2)));
typedef unsigned int swift_uint3  __attribute__((__ext_vector_type__(3)));
typedef unsigned int swift_uint4  __attribute__((__ext_vector_type__(4)));
#endif

#if !defined(SWIFT_PASTE)
# define SWIFT_PASTE_HELPER(x, y) x##y
# define SWIFT_PASTE(x, y) SWIFT_PASTE_HELPER(x, y)
#endif
#if !defined(SWIFT_METATYPE)
# define SWIFT_METATYPE(X) Class
#endif
#if !defined(SWIFT_CLASS_PROPERTY)
# if __has_feature(objc_class_property)
#  define SWIFT_CLASS_PROPERTY(...) __VA_ARGS__
# else
#  define SWIFT_CLASS_PROPERTY(...) 
# endif
#endif
#if !defined(SWIFT_RUNTIME_NAME)
# if __has_attribute(objc_runtime_name)
#  define SWIFT_RUNTIME_NAME(X) __attribute__((objc_runtime_name(X)))
# else
#  define SWIFT_RUNTIME_NAME(X) 
# endif
#endif
#if !defined(SWIFT_COMPILE_NAME)
# if __has_attribute(swift_name)
#  define SWIFT_COMPILE_NAME(X) __attribute__((swift_name(X)))
# else
#  define SWIFT_COMPILE_NAME(X) 
# endif
#endif
#if !defined(SWIFT_METHOD_FAMILY)
# if __has_attribute(objc_method_family)
#  define SWIFT_METHOD_FAMILY(X) __attribute__((objc_method_family(X)))
# else
#  define SWIFT_METHOD_FAMILY(X) 
# endif
#endif
#if !defined(SWIFT_NOESCAPE)
# if __has_attribute(noescape)
#  define SWIFT_NOESCAPE __attribute__((noescape))
# else
#  define SWIFT_NOESCAPE 
# endif
#endif
#if !defined(SWIFT_RELEASES_ARGUMENT)
# if __has_attribute(ns_consumed)
#  define SWIFT_RELEASES_ARGUMENT __attribute__((ns_consumed))
# else
#  define SWIFT_RELEASES_ARGUMENT 
# endif
#endif
#if !defined(SWIFT_WARN_UNUSED_RESULT)
# if __has_attribute(warn_unused_result)
#  define SWIFT_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
# else
#  define SWIFT_WARN_UNUSED_RESULT 
# endif
#endif
#if !defined(SWIFT_NORETURN)
# if __has_attribute(noreturn)
#  define SWIFT_NORETURN __attribute__((noreturn))
# else
#  define SWIFT_NORETURN 
# endif
#endif
#if !defined(SWIFT_CLASS_EXTRA)
# define SWIFT_CLASS_EXTRA 
#endif
#if !defined(SWIFT_PROTOCOL_EXTRA)
# define SWIFT_PROTOCOL_EXTRA 
#endif
#if !defined(SWIFT_ENUM_EXTRA)
# define SWIFT_ENUM_EXTRA 
#endif
#if !defined(SWIFT_CLASS)
# if __has_attribute(objc_subclassing_restricted)
#  define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) __attribute__((objc_subclassing_restricted)) SWIFT_CLASS_EXTRA
#  define SWIFT_CLASS_NAMED(SWIFT_NAME) __attribute__((objc_subclassing_restricted)) SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
# else
#  define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
#  define SWIFT_CLASS_NAMED(SWIFT_NAME) SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
# endif
#endif
#if !defined(SWIFT_RESILIENT_CLASS)
# if __has_attribute(objc_class_stub)
#  define SWIFT_RESILIENT_CLASS(SWIFT_NAME) SWIFT_CLASS(SWIFT_NAME) __attribute__((objc_class_stub))
#  define SWIFT_RESILIENT_CLASS_NAMED(SWIFT_NAME) __attribute__((objc_class_stub)) SWIFT_CLASS_NAMED(SWIFT_NAME)
# else
#  define SWIFT_RESILIENT_CLASS(SWIFT_NAME) SWIFT_CLASS(SWIFT_NAME)
#  define SWIFT_RESILIENT_CLASS_NAMED(SWIFT_NAME) SWIFT_CLASS_NAMED(SWIFT_NAME)
# endif
#endif
#if !defined(SWIFT_PROTOCOL)
# define SWIFT_PROTOCOL(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_PROTOCOL_EXTRA
# define SWIFT_PROTOCOL_NAMED(SWIFT_NAME) SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_PROTOCOL_EXTRA
#endif
#if !defined(SWIFT_EXTENSION)
# define SWIFT_EXTENSION(M) SWIFT_PASTE(M##_Swift_, __LINE__)
#endif
#if !defined(OBJC_DESIGNATED_INITIALIZER)
# if __has_attribute(objc_designated_initializer)
#  define OBJC_DESIGNATED_INITIALIZER __attribute__((objc_designated_initializer))
# else
#  define OBJC_DESIGNATED_INITIALIZER 
# endif
#endif
#if !defined(SWIFT_ENUM_ATTR)
# if __has_attribute(enum_extensibility)
#  define SWIFT_ENUM_ATTR(_extensibility) __attribute__((enum_extensibility(_extensibility)))
# else
#  define SWIFT_ENUM_ATTR(_extensibility) 
# endif
#endif
#if !defined(SWIFT_ENUM)
# define SWIFT_ENUM(_type, _name, _extensibility) enum _name : _type _name; enum SWIFT_ENUM_ATTR(_extensibility) SWIFT_ENUM_EXTRA _name : _type
# if __has_feature(generalized_swift_name)
#  define SWIFT_ENUM_NAMED(_type, _name, SWIFT_NAME, _extensibility) enum _name : _type _name SWIFT_COMPILE_NAME(SWIFT_NAME); enum SWIFT_COMPILE_NAME(SWIFT_NAME) SWIFT_ENUM_ATTR(_extensibility) SWIFT_ENUM_EXTRA _name : _type
# else
#  define SWIFT_ENUM_NAMED(_type, _name, SWIFT_NAME, _extensibility) SWIFT_ENUM(_type, _name, _extensibility)
# endif
#endif
#if !defined(SWIFT_UNAVAILABLE)
# define SWIFT_UNAVAILABLE __attribute__((unavailable))
#endif
#if !defined(SWIFT_UNAVAILABLE_MSG)
# define SWIFT_UNAVAILABLE_MSG(msg) __attribute__((unavailable(msg)))
#endif
#if !defined(SWIFT_AVAILABILITY)
# define SWIFT_AVAILABILITY(plat, ...) __attribute__((availability(plat, __VA_ARGS__)))
#endif
#if !defined(SWIFT_WEAK_IMPORT)
# define SWIFT_WEAK_IMPORT __attribute__((weak_import))
#endif
#if !defined(SWIFT_DEPRECATED)
# define SWIFT_DEPRECATED __attribute__((deprecated))
#endif
#if !defined(SWIFT_DEPRECATED_MSG)
# define SWIFT_DEPRECATED_MSG(...) __attribute__((deprecated(__VA_ARGS__)))
#endif
#if !defined(SWIFT_DEPRECATED_OBJC)
# if __has_feature(attribute_diagnose_if_objc)
#  define SWIFT_DEPRECATED_OBJC(Msg) __attribute__((diagnose_if(1, Msg, "warning")))
# else
#  define SWIFT_DEPRECATED_OBJC(Msg) SWIFT_DEPRECATED_MSG(Msg)
# endif
#endif
#if defined(__OBJC__)
#if !defined(IBSegueAction)
# define IBSegueAction 
#endif
#endif
#if !defined(SWIFT_EXTERN)
# if defined(__cplusplus)
#  define SWIFT_EXTERN extern "C"
# else
#  define SWIFT_EXTERN extern
# endif
#endif
#if !defined(SWIFT_CALL)
# define SWIFT_CALL __attribute__((swiftcall))
#endif
#if !defined(SWIFT_INDIRECT_RESULT)
# define SWIFT_INDIRECT_RESULT __attribute__((swift_indirect_result))
#endif
#if !defined(SWIFT_CONTEXT)
# define SWIFT_CONTEXT __attribute__((swift_context))
#endif
#if !defined(SWIFT_ERROR_RESULT)
# define SWIFT_ERROR_RESULT __attribute__((swift_error_result))
#endif
#if defined(__cplusplus)
# define SWIFT_NOEXCEPT noexcept
#else
# define SWIFT_NOEXCEPT 
#endif
#if !defined(SWIFT_C_INLINE_THUNK)
# if __has_attribute(always_inline)
# if __has_attribute(nodebug)
#  define SWIFT_C_INLINE_THUNK inline __attribute__((always_inline)) __attribute__((nodebug))
# else
#  define SWIFT_C_INLINE_THUNK inline __attribute__((always_inline))
# endif
# else
#  define SWIFT_C_INLINE_THUNK inline
# endif
#endif
#if defined(_WIN32)
#if !defined(SWIFT_IMPORT_STDLIB_SYMBOL)
# define SWIFT_IMPORT_STDLIB_SYMBOL __declspec(dllimport)
#endif
#else
#if !defined(SWIFT_IMPORT_STDLIB_SYMBOL)
# define SWIFT_IMPORT_STDLIB_SYMBOL 
#endif
#endif
#if defined(__OBJC__)
#if __has_feature(objc_modules)
#if __has_warning("-Watimport-in-framework-header")
#pragma clang diagnostic ignored "-Watimport-in-framework-header"
#endif
@import AVFoundation;
@import CoreFoundation;
@import Flutter;
@import ObjectiveC;
@import UIKit;
#endif

#endif
#pragma clang diagnostic ignored "-Wproperty-attribute-mismatch"
#pragma clang diagnostic ignored "-Wduplicate-method-arg"
#if __has_warning("-Wpragma-clang-attribute")
# pragma clang diagnostic ignored "-Wpragma-clang-attribute"
#endif
#pragma clang diagnostic ignored "-Wunknown-pragmas"
#pragma clang diagnostic ignored "-Wnullability"
#pragma clang diagnostic ignored "-Wdollar-in-identifier-extension"

#if __has_attribute(external_source_symbol)
# pragma push_macro("any")
# undef any
# pragma clang attribute push(__attribute__((external_source_symbol(language="Swift", defined_in="camerax_ios",generated_declaration))), apply_to=any(function,enum,objc_interface,objc_category,objc_protocol))
# pragma pop_macro("any")
#endif

#if defined(__OBJC__)
@protocol FlutterPluginRegistrar;

SWIFT_CLASS("_TtC11camerax_ios16CameraXiOSPlugin")
@interface CameraXiOSPlugin : NSObject <FlutterPlugin>
+ (void)registerWithRegistrar:(id <FlutterPluginRegistrar> _Nonnull)registrar;
- (nonnull instancetype)init OBJC_DESIGNATED_INITIALIZER;
@end

@class AVCaptureVideoPreviewLayer;
@class AVCaptureSession;
@class NSCoder;

SWIFT_CLASS("_TtC11camerax_ios11PreviewView")
@interface PreviewView : UIView <FlutterPlatformView>
SWIFT_CLASS_PROPERTY(@property (nonatomic, class, readonly) Class _Nonnull layerClass;)
+ (Class _Nonnull)layerClass SWIFT_WARN_UNUSED_RESULT;
@property (nonatomic, readonly, strong) AVCaptureVideoPreviewLayer * _Nonnull previewLayer;
@property (nonatomic, strong) AVCaptureSession * _Nullable session;
@property (nonatomic) AVLayerVideoGravity _Nonnull videoGravity;
- (void)removeFromSuperview;
- (UIView * _Nonnull)view SWIFT_WARN_UNUSED_RESULT;
- (nonnull instancetype)initWithFrame:(CGRect)frame OBJC_DESIGNATED_INITIALIZER;
- (nullable instancetype)initWithCoder:(NSCoder * _Nonnull)coder OBJC_DESIGNATED_INITIALIZER;
@end


SWIFT_CLASS("_TtC11camerax_ios18PreviewViewFactory")
@interface PreviewViewFactory : NSObject <FlutterPlatformViewFactory>
SWIFT_CLASS_PROPERTY(@property (nonatomic, class, readonly, strong) PreviewViewFactory * _Nonnull shared;)
+ (PreviewViewFactory * _Nonnull)shared SWIFT_WARN_UNUSED_RESULT;
- (nonnull instancetype)init SWIFT_UNAVAILABLE;
+ (nonnull instancetype)new SWIFT_UNAVAILABLE_MSG("-init is unavailable");
- (id <FlutterPlatformView> _Nonnull)createWithFrame:(CGRect)frame viewIdentifier:(int64_t)viewId arguments:(id _Nullable)args SWIFT_WARN_UNUSED_RESULT;
- (PreviewView * _Nullable)retrieveView:(int64_t)viewId SWIFT_WARN_UNUSED_RESULT;
@end

#endif
#if __has_attribute(external_source_symbol)
# pragma clang attribute pop
#endif
#if defined(__cplusplus)
#endif
#pragma clang diagnostic pop
#endif

#else
#error unsupported Swift architecture
#endif

The ffigen.yaml is like this:

# Run with `dart run ffigen --config ffigen.yaml`.
name: CameraXiOSLibrary
description: iOS Library for CameraX.
language: objc
output: "lib/src/ffi1.g.dart"
compiler-opts:
  - '-F/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks'
  - '-F/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/iOSSupport/System/Library/Frameworks'
headers:
  entry-points:
    - '/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/AVFoundation.framework/Headers/AVFoundation.h'
    - 'example/build/ios/Debug-iphonesimulator/camerax_ios/camerax_ios.framework/Headers/camerax_ios-Swift.h'
exclude-all-by-default: true
objc-interfaces:
  include:
    - AVCaptureSession
    - AVCaptureDevice
    - AVCaptureInput
    - AVCaptureDeviceInput
    - PreviewView
    - PreviewViewFactory
  module:
    PreviewView: camerax_ios
    PreviewViewFactory: camerax_ios
typedefs:
  include:
    - AVMediaType
    - AVCaptureDeviceType
    - AVLayerVideoGravity
globals:
  include:
    - AVMediaType.*
    - AVCaptureDeviceType.*
    - AVLayerVideoGravity.*
enums:
  include:
    - AVCaptureDevicePosition

When I run the ffigen command, there is an error caused the AVLayerVideoGravity can't be generated correctly.

...
[SEVERE] :     ./example/build/ios/Debug-iphonesimulator/camerax_ios/camerax_ios.framework/Headers/camerax_ios-Swift.h:671:23: error: unknown type name 'AVLayerVideoGravity' [Semantic Issue]
...

Seems the import statement is not figured out by ffigen. How can I fix this?

Jul 11 '24 00:07 yanshouwang

That header is generated by the swift compiler, and the header parsing is done by clang, so ffigen doesn't directly get involved in that error.

I think the first thing to try is to fiddle with the clang flags using the compiler-opts option in the config. Try adding a -F flag to import the AVFoundation framework (-FAVFoundation might work, or you might need to specify the full path to the framework).

Last time I wrapped a swift framework, I found that I also had to specify the iOS version and sysroot. Check out this WebKit prototype for an example.

Jul 11 '24 01:07 liamappelbe

That header is generated by the swift compiler, and the header parsing is done by clang, so ffigen doesn't directly get involved in that error.

I think the first thing to try is to fiddle with the clang flags using the compiler-opts option in the config. Try adding a -F flag to import the AVFoundation framework (-FAVFoundation might work, or you might need to specify the full path to the framework).

Last time I wrapped a swift framework, I found that I also had to specify the iOS version and sysroot. Check out this WebKit prototype for an example.

Thanks, I'll try this later.

Jul 11 '24 01:07 yanshouwang

@liamappelbe I have tried these steps but the error still exists.

The objc-interfaces is generated correctly, but the AVLayterVideoGravity which is a typedef can't be generated.

Jul 11 '24 02:07 yanshouwang

The objc-interfaces is generated correctly, but the AVLayterVideoGravity which is a typedef can't be generated.

I think AVLayerVideoGravity is a struct. What header file is it defined in? If you manually edit the generated header (camerax_ios-Swift.h) to import the AVLayerVideoGravity header, does the error go away?

Jul 11 '24 04:07 liamappelbe

The objc-interfaces is generated correctly, but the AVLayterVideoGravity which is a typedef can't be generated.

I think AVLayerVideoGravity is a struct. What header file is it defined in? If you manually edit the generated header (camerax_ios-Swift.h) to import the AVLayerVideoGravity header, does the error go away?

The AVLayerVideoGravity is a structure in swift but typealias in objc

typedef NSString *AVLayerVideoGravity;

I've imported the AVFoundation header, do I need to import another header?

Jul 11 '24 04:07 yanshouwang

I've imported the AVFoundation header, do I need to import another header?

I'm not sure. The error you're describing is a clang compile error, so there's nothing I can do to fix it in ffigen. You'll basically have figure out what compiler-opts are needed to fix the error.

It's also possible you need code changes in your swift file. Maybe the issue is that AVLayerVideoGravity is a struct in Swift, but a typedef for a NSString* in ObjC? That seems weird.

Another possible issue is that I don't think you can @objc annotate methods that accept or return structs. So I'm surprised the swift compiler doesn't complain about the videoGravity method. You'll probably need to write a wrapper class for AVLayerVideoGravity that encapsulates it and exposes its fields as getters/setters.

Jul 11 '24 05:07 liamappelbe