我想知道如何在 Swift 中初始化自定义类型的双向数组

Question

具体例子如下：

enum Segments {
    case s1, s2, s3, noParent, empty
}

struct StructA {
    var id: Segments = .empty
    var parent: Segments = .empty
    var value = 0.0
}

class ClassA {
    let StructAMap: Array<Array<StructA>> = []

    init {
    for help in 1...2 {
        StructAMap[help][1].id = Segments.s1
        StructAMap[help][1].parent = Segments.noParent
        StructAMap[help][1].value = 0.0
        StructAMap[help][2].id = Segments.s2
        StructAMap[help][2].parent = Segments.s1
        // etc...

     }
     StructAMap[1][3].id = Segments.s1
     StructAMap[2][3].value = 3.0 
     // etc...
     }
}

如果我尝试这样做，我会收到此错误：无法分配给 'Segments'

类型的不可变值

如果我将 StructAMap 更改为 var 它实际上不起作用，但我收到的错误消息较少这是结构图，不会更改；这就是为什么我想要它作为一个常数。

非常感谢。

更新：评论 #1

这似乎解决了一些错误错误并且非常聪明。所以现在我正在操场上尝试。我想测试地图是否正常工作，但遇到执行失败:

enum Segments {
    case s1, s2, s3, noParent, empty
}

struct StructA {
    var id: Segments = .empty
    var parent: Segments = .empty
    var value = 0.0
}

class ClassA {
    let StructAMap: Array<Array<StructA>>

    init() {
        var StructAMap: Array<Array<StructA>> = []
        for help in 1...2 {
            StructAMap[help][1].id = Segments.s1
            StructAMap[help][1].parent = Segments.noParent
            StructAMap[help][1].value = 0.0
            StructAMap[help][2].id = Segments.s2
            StructAMap[help][2].parent = Segments.s1
        }
        StructAMap[1][3].id = Segments.s1
        StructAMap[2][3].value = 3.0
        self.StructAMap = StructAMap
    }
}

var paciente1 = ClassA()

println("\(paciente1.StructAMap[1][1])")

控制台输出：

游乐场执行失败：执行被中断，原因：EXC_BAD_INSTRUCTION（代码=EXC_I386_INVOP，子代码=0x0）。 * 线程 #1：tid = 0xcea9d，0x000000010c09a14e PlaygroundLoggerSwift.Array.subscript.nativePinningMutableAddressor (Swift.Int) -> A + 238, queue = 'com.apple.main-thread', stop reason = EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0) * frame #0: 0x000000010c09a14e PlaygroundLoggerSwift.Array.subscript.nativePinningMutableAddressor (Swift.Int) -> A + 238 帧 #1: 0x0000000116937e3f $lldb_expr74__lldb_expr_74.ClassA.init (self=0x00007f905a5000e0)() -> __lldb_expr_74.ClassA + 1695 at MyPlayground.playground:122 frame #2: 0x0000000116938444 $__lldb_expr74__lldb_expr_74.ClassA.__allocating_init ($metatype=0x000000011693ac40)() -> __lldb_expr_74.ClassA + 116 at :0 帧#3：0x00000001169370df $__lldb_expr74main + 223 at MyPlayground.playground:134 frame #4: 0x000000010bb32710 MyPlayground frame #5: 0x000000010bb365f1 MyPlayground从@callee_owned () -> (@unowned ()) 到@callee_owned (@in ()) -> (@out ()) + 17 frame #6: 0x000000010bb351f1 MyPlaygroundpartial apply forwarder for reabstraction thunk helper from @callee_owned () -> (@unowned ()) to @callee_owned (@in ()) -> (@out ()) + 81 frame #7: 0x000000010bb36620 MyPlayground 从@callee_owned (@in ()) -> (@out ()) 到@callee_owned () -> (@unowned ( )) + 32 第 8 帧：0x000000010bb36657 MyPlaygroundreabstraction thunk helper from @callee_owned () -> (@unowned ()) to @callee_unowned @objc_block () -> (@unowned ()) + 39 frame #9: 0x000000010c17f41c CoreFoundation__CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK + 12 第 10 帧：0x000000010c175165 CoreFoundation__CFRunLoopDoBlocks + 341 frame #11: 0x000000010c174923 CoreFoundation__CFRunLoopRun + 851 第 12 帧：0x000000010c174366 CoreFoundationCFRunLoopRunSpecific + 470 frame #13: 0x000000010c222661 CoreFoundationCFRunLoopRun + 97 第 14 帧：0x000000010bb32dc2 MyPlaygroundmain + 1714 frame #15: 0x000000010ee0d145 libdyld.dylibstart + 1 第 16 帧：0x000000010ee0d145 libdyld.dylib`start + 1

更新 2：

我想我找到了进一步调整的方法。

class ClassA {
    let xSize = 6 // whatever
    let ySize = 6 // whatever
    static let StructAMap: Array<Array<StructA>> = {
        var tempStructAMap = Array(count: ySize, repeatedValue: 
                         Array(count: xSize, repeatedValue: StructA()))
        for help in 1...2 {
            tempStructAMap[help][1].id = Segments.s1
            tempStructAMap[help][1].parent = Segments.noParent
            tempStructAMap[help][1].value = 0.0
            tempStructAMap[help][2].id = Segments.s2
            tempStructAMap[help][2].parent = Segments.s1
            // etc...

        }
        tempStructAMap[1][3].id = Segments.s1
        tempStructAMap[2][3].value = 3.0
        // etc...
        return tempStructAMap
    }()
}

Answer 1

在 init() 中，使用局部变量构建数组，然后将其分配给实例常量：

class ClassA {
    let xSize = 6 // whatever
    let ySize = 6 // whatever
    let StructAMap: Array<Array<StructA>>

    init() {
        var StructAMap = Array(count: ySize, repeatedValue: 
                         Array(count: xSize, repeatedValue: StructA()))
        for help in 1...2 {
            StructAMap[help][1].id = Segments.s1
            StructAMap[help][1].parent = Segments.noParent
            StructAMap[help][1].value = 0.0
            StructAMap[help][2].id = Segments.s2
            StructAMap[help][2].parent = Segments.s1
            // etc...

        }
        StructAMap[1][3].id = Segments.s1
        StructAMap[2][3].value = 3.0
        // etc...
        self.StructAMap = StructAMap
    }
}

我想知道如何在 Swift 中初始化自定义类型的双向数组

I would please like to know how to initialize a bidimenstional array of a custom type in Swift

arrays

initialization

immutability

swift