如何快速编写HID函数Handle_DeviceMatchingCallback？

Question

我有一个关于HID的程序。 但这是用Objective-C编写的。 这是一个项目，我的朋友们只知道敏捷。 所以我想将其转换为swift，但我不知道如何编写该函数。

对象代码：

 /* Creating The HID Manager */
 IOHIDManagerRef manager = IOHIDManagerCreate(kCFAllocatorDefault, kIOHIDOptionsTypeNone);
 /* Dictionary Matching - All the devices */
 IOHIDManagerSetDeviceMatching(manager,NULL);
 /* Connected and Disconnected Call Backs */
 IOHIDManagerRegisterDeviceMatchingCallback(manager,  &Handle_DeviceMatchingCallback , NULL);
 IOHIDManagerRegisterDeviceRemovalCallback(manager, &Handle_DeviceRemovalCallback,NULL);

回调函数为：

static void Handle_DeviceMatchingCallback(void *inContext,
                                          IOReturn inResult,
                                          void *inSender,
                                          IOHIDDeviceRef inIOHIDDeviceRef)
{
    printf("Connected\n");



}


static void Handle_DeviceRemovalCallback(void *inContext,
                                         IOReturn inResult,
                                         void *inSender,
                                         IOHIDDeviceRef inIOHIDDeviceRef)
{
    printf("Disconnected\n");
}

---

很快

我写了Handle_DeviceMatchingCallback()为

func Handle_DeviceMatchingCallback(inContext: UnsafeMutableRawPointer!, inResult: IOReturn, inSender: UnsafeMutableRawPointer!, inIOHIDDeviceRef: IOHIDDevice)
{
    print("Connected")
}

但是我不能将函数传递给IOHIDManagerRegisterDeviceMatchingCallback() 。

怎么做？

Answer 1

处理您的情况的一种方法是将回调设为闭包：

let Handle_DeviceMatchingCallback: IOHIDDeviceCallback = {context, result, sender, device in
    print("Connected")
}
let Handle_DeviceRemovalCallback: IOHIDDeviceCallback = {context, result, sender, device in
    print("Disconnected")
}

---

否则，您需要声明具有与IOHIDDeviceCallback定义的签名完全相同的签名的回调函数。

 typealias IOHIDDeviceCallback = (UnsafeMutableRawPointer?, IOReturn, UnsafeMutableRawPointer?, IOHIDDevice) -> Void 

（摘自Xcode的快速帮助。）

func Handle_DeviceMatchingCallback(_ context: UnsafeMutableRawPointer?, _ result: IOReturn, _ sender: UnsafeMutableRawPointer?, _ device: IOHIDDevice) {
    print("Connected")
}
func Handle_DeviceRemovalCallback(_ context: UnsafeMutableRawPointer?, _ result: IOReturn, _ sender: UnsafeMutableRawPointer?, _ device: IOHIDDevice) {
    print("Disconnected")
}