给定一个没有修饰符的键的键码，我想产生按下 shift+键的结果。示例:对于标准美式键盘，+ 给出 >.

相关函数是 UCKeytranslate，但我需要一些帮助才能正确了解细节。下面的代码片段是一个完整的程序，可以在 Xcode 中运行。程序的意图是 以产生字符 >。

程序的结果是:

Keyboard: <TSMInputSource 0x10051a930> KB Layout: U.S. (id=0)
Layout: 0x0000000102802000
Status: -50
UnicodeString: 97
String: a
Done
Program ended with exit code: 0

获取布局的部分似乎可以正常工作，但状态代码表明出了点问题。但是什么？

import Foundation
import Cocoa
import Carbon
import AppKit

// The current text input source (read keyboard) has a layout in which
// we can lookup how key-codes are resolved.

// Get the a reference keyboard using the current layout.
var unmanagedKeyboard = TISCopyCurrentKeyboardLayoutInputSource()
var keyboard = unmanagedKeyboard.takeUnretainedValue() as TISInputSource
print("Keyboard: ") ; println(keyboard)

// Get the layout
var ptrLayout   = TISGetInputSourceProperty(keyboard, kTISPropertyUnicodeKeyLayoutData)
var layout = UnsafeMutablePointer<UCKeyboardLayout>(ptrLayout)
print("Layout: "); println(layout)

// Let's see what the result of pressing  <shift> and <period>  (hopefully the result is > )
var keycode             = UInt16(kVK_ANSI_Period)                           // Keycode for <period>
var keyaction           = UInt16(kUCKeyActionDisplay)                       // The user is requesting information for key display
var modifierKeyState    = UInt32(1 << 17)                                   // Shift
var keyboardType        = UInt32(LMGetKbdType())
var keyTranslateOptions = UInt32(1 << kUCKeyTranslateNoDeadKeysBit)
var deadKeyState        = UnsafeMutablePointer<UInt32>(bitPattern: 0)       // Is 0 the correct value?
var maxStringLength     = UniCharCount(4)                                   // uint32
var actualStringLength  = UnsafeMutablePointer<UniCharCount>.alloc(1)       //
actualStringLength[0]=16
var unicodeString       = UnsafeMutablePointer<UniChar>.alloc(255)
unicodeString[0] = 97 // a (this value is meant to be overwritten by UCKeyTranslate)
var str = NSString(characters: unicodeString, length: 1)
var result = UCKeyTranslate(layout, keycode, keyaction, modifierKeyState, keyboardType, keyTranslateOptions,
                            deadKeyState, maxStringLength, actualStringLength, unicodeString)

// Print the results
print("Status: "); println(result)
var unichar = unicodeString[0];
print("UnicodeString: "); println(String(unichar))
print("String: "); println(str)
println("Done")

编辑

我已经按照 Ken Thomases 的建议重写了代码片段。 一些技巧来自:Graphite还使用了使用键码的 Swift 程序。

import Foundation
import Cocoa
import Carbon
import AppKit

// The current text input source (read keyboard) has a layout in which
// we can lookup how key-codes are resolved.

// Get the a reference keyboard using the current layout.
let keyboard = TISCopyCurrentKeyboardInputSource().takeRetainedValue()
let rawLayoutData = TISGetInputSourceProperty(keyboard, kTISPropertyUnicodeKeyLayoutData)
print("Keyboard: ") ; println(keyboard)

// Get the layout
var layoutData      = unsafeBitCast(rawLayoutData, CFDataRef.self)
var layout: UnsafePointer<UCKeyboardLayout> = unsafeBitCast(CFDataGetBytePtr(layoutData), UnsafePointer<UCKeyboardLayout>.self)
print("Layout: "); println(layout)

print("KbdType "); println(LMGetKbdType()) // Sanity check (prints 44)

var keycode             = UInt16(kVK_ANSI_Period)                         // Keycode for a
var keyaction           = UInt16(kUCKeyActionDisplay)
var modifierKeyState    = UInt32(1 << 1)                                  // Shift
var keyboardType        = UInt32(LMGetKbdType())
var keyTranslateOptions = OptionBits(kUCKeyTranslateNoDeadKeysBit)
var deadKeyState        = UInt32(0)                                       // Is 0 the correct value?
var maxStringLength     = UniCharCount(4)                                 // uint32
var chars: [UniChar]    = [0,0,0,0]
var actualStringLength  = UniCharCount(1)
var result = UCKeyTranslate(layout, keycode, keyaction, modifierKeyState, keyboardType, keyTranslateOptions,
                            &deadKeyState, maxStringLength, &actualStringLength, &chars)
// Print the results
print("Status: "); println(result)
print("Out:"); println(UnicodeScalar(chars[0]))
println("Done")

最佳答案

对于 kTISPropertyUnicodeKeyLayoutData , TISGetInputSourceProperty()返回 CFDataRef .您需要获取其字节指针并将其视为指向 UCKeyboardLayout 的指针.我不认为那是你用这条线做的:

var layout = UnsafeMutablePointer<UCKeyboardLayout>(ptrLayout)

我不太了解 Swift，但它可能会像这样工作:

var layout = UnsafePointer<UCKeyboardLayout>(CFDataGetBytePtr(ptrLayout))

或者也许:

var layout = CFDataGetBytePtr(ptrLayout) as UnsafePointer<UCKeyboardLayout>

此外，kUCKeyActionDisplay大多没用。它的目的是返回 key 的标签，但它甚至不能可靠地做到这一点。您可能想使用 kUCKeyActionDown .

对于修饰符，您想使用 Carbon-era shiftKey位掩码右移 8 位(如 UCKeyTranslate() 的文档中所示)。 shiftKey是1 << 9 , 所以 shiftKey >> 8是1 << 1 .

对于选项，您应该能够使用 kUCKeyTranslateNoDeadKeysMask为简单起见。相当于1 << kUCKeyTranslateNoDeadKeysBit .

是的，0 是 deadKeyState 的正确值对于初始击键或您不想应用任何先前的死键状态的击键。

我不确定您为什么评论 maxStringLength符合 uint32 .该类型与最大字符串长度完全无关。 maxStringLength是 UTF-16 代码单元(API 错误地称为“字符”)的最大数量 UCKeyTranslate()应该写入提供的缓冲区。它基本上是缓冲区大小，以 UniChar 衡量s(不是字节)。在你的情况下，它应该是 255。或者，因为你可能不希望从一次击键中获得 255 个“字符”，你可以减小缓冲区的大小并设置 maxStringLength匹配任何内容。

您对 str 的处理很奇怪。您从 unicodeString 构建它调用前的缓冲区 UCKeyTranslate() .你希望字符串对象的值因为 UCKeyTranslate() 而改变吗？更改 unicodeString 的内容？它不是。如果是这样，那将是 NSString 中的一个非常严重的错误。 .你应该构造 NSString从缓冲区之后 UCKeyTranslate()已成功填充该缓冲区。当然，你应该通过 actualStringLength作为构造 NSString 时的长度参数.

关于objective-c - 如何使用UCKeyTranslate，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27735217/