使用 IOKit 和 Swift 进行简单的键重映射

Question

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在 macOS 中， IOKit HID API 可用于键重映射。 在下面的示例中，使用 Objective-C将 A键重新映射到B键，反之亦然。

是否可以使用最新的 Swift 5.5 以编程方式进行相同的重新映射？ 如果可以的话，下面的例子如何用 Swift 重写？

或者是否有新的、更现代的 API 可以与 Swift 一起使用来完成相同的任务？

---

#import <Foundation/Foundation.h>
#import <IOKit/hidsystem/IOHIDEventSystemClient.h>
#import <IOKit/hidsystem/IOHIDServiceClient.h>
#import <IOKit/hid/IOHIDUsageTables.h>
 
int main(int argc, char *argv[])
{
    IOHIDEventSystemClientRef system;
    CFArrayRef services;
 
    uint64_t aKey = 0x700000004;
    uint64_t bKey = 0x700000005;
 
    NSArray *map = @[
                     @{@kIOHIDKeyboardModifierMappingSrcKey:@(aKey),
                        @kIOHIDKeyboardModifierMappingDstKey:@(bKey)},
                     @{@kIOHIDKeyboardModifierMappingSrcKey:@(bKey),
                        @kIOHIDKeyboardModifierMappingDstKey:@(aKey)},
                     ];
 
    system = IOHIDEventSystemClientCreateSimpleClient(kCFAllocatorDefault);
    services = IOHIDEventSystemClientCopyServices(system);
    for(CFIndex i = 0; i < CFArrayGetCount(services); i++) {
        IOHIDServiceClientRef service = (IOHIDServiceClientRef)CFArrayGetValueAtIndex(services, i);
        if(IOHIDServiceClientConformsTo(service, kHIDPage_GenericDesktop, kHIDUsage_GD_Keyboard)) {
            IOHIDServiceClientSetProperty(service, CFSTR(kIOHIDUserKeyUsageMapKey), (CFArrayRef)map);
        }
    }
 
    CFRelease(services);
    CFRelease(system);
 
    return 0;
}

Answer 1

你可以像这样在 Swift 5.5 中重写你被诅咒的代码：

import Cocoa

class ViewController: NSViewController {

  override func viewDidLoad() {
    super.viewDidLoad()
    
     remapKeys()
  }

  func remapKeys() {
    let aKey: UInt64 = 0x700000004
    let bKey: UInt64 = 0x700000005
    
    let map: [[String: UInt64]] = [
      [kIOHIDKeyboardModifierMappingSrcKey:aKey,
       kIOHIDKeyboardModifierMappingDstKey:bKey],
      [kIOHIDKeyboardModifierMappingSrcKey:bKey,
       kIOHIDKeyboardModifierMappingDstKey:aKey],
    ]
    
    let system = IOHIDEventSystemClientCreateSimpleClient(kCFAllocatorDefault)
    let services = IOHIDEventSystemClientCopyServices(system)
    
    for service in services as! [IOHIDServiceClient] {
      if((IOHIDServiceClientConformsTo(service, UInt32((kHIDPage_GenericDesktop)), UInt32(kHIDUsage_GD_Keyboard))) != 0) {
        IOHIDServiceClientSetProperty(service, kIOHIDUserKeyUsageMapKey as CFString, map as CFArray)
      }
    }
  }
}

如果您创建一个包含这些导入的桥接头：

#import <IOKit/hidsystem/IOHIDEventSystemClient.h>
#import <IOKit/hidsystem/IOHIDServiceClient.h>
#import <IOKit/hid/IOHIDUsageTables.h>