Question

我是swift和IOS的新手，我不知道将变量（mylessons）与其他文件（.swift）或（.json）分开来实现MVC。谁能教我？非常感谢

declare @outputtable table (start datetime, stop datetime)
declare @curstart datetime, @curstop datetime, @curdiff int
declare @outputstart datetime

DECLARE cur CURSOR FOR   
select start, stop, datediff(ss, stop, LEAD(start) over (order by rn))
from @t
OPEN cur  

FETCH NEXT FROM cur   
INTO @curstart, @curstop, @curdiff 

WHILE @@FETCH_STATUS = 0  
BEGIN       
    if (@outputstart is null)
        set @outputstart = @curstart

    if (@curdiff > 25)
    begin
        insert into @outputtable values (@outputstart, @curstop)
        set @outputstart = null
    end

    FETCH NEXT FROM cur   
    INTO @curstart, @curstop, @curdiff
END   
CLOSE cur;  
DEALLOCATE cur;  

insert into @outputtable values (@outputstart, @curstop)

select * from @outputtable

Answer 1

参考您给出的代码段，为了实现MVC，您应该为课程创建一个包含所需属性的模型，因此，mylessons数组应该包含课程的对象。

如果要分隔不同文件中的图层（这是一个好主意），您可能需要创建一个文件 - 例如Lesson.swift，其中包含您的模型，如下所示：

<强> Lesson.swift：

// Note that I decalred it as 'struct'
// instead of 'class' do what is suitable
// for your requirements...
struct Lesson {
    var title:String?
    var subtitle: String?
    var bgImage: String?
    var lesImage: String?
    var lesTitle: String?
}

<强>的ViewController：

// note that myLessons data type is: '[Lesson]'
var myLessons =  [Lesson(title: "Posture",
                         subtitle: "Set up your body",
                         bgImage: "Ln1",
                         lesImage: "Posture_pic",
                         lesTitle: "So starting from the head and moving down",
                         lesContent: "1) The top back part of your head should be pointing up..")]

备注：如果您正在实施tableView:cellForRowAtIndexPath:，则应该访问每行的课程，如下所示：

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    //....

    let currentLesson = myLessons[indexPath.row]

    // ...
}

同时

如果您能够将给定的字典转换为课程对象，实际上可以通过添加以下字典扩展来实现它将会很好：

extension Dictionary where Key: ExpressibleByStringLiteral, Value: ExpressibleByStringLiteral { func toLesson() -> Lesson { var lessonToRetrun = Lesson() if let title = self["title"] as? String { lessonToRetrun.title = title } if let subtitle = self["subtitle"] as? String { lessonToRetrun.subtitle = subtitle } if let bgimage = self["bgimage"] as? String { lessonToRetrun.bgImage = bgimage } if let lesimage = self["lesimage"] as? String { lessonToRetrun.lesImage = lesimage } if let lestitle = self["lestitle"] as? String { lessonToRetrun.lesTitle = lestitle } if let lescontent = self["lescontent"] as? String { lessonToRetrun.lesContent = lescontent } return lessonToRetrun } }

你将能够做到：

let lessonDict = ["title":"Posture", "subtitle":"Set up your body", "bgimage":"Ln1", "lesimage":"Posture_pic", "lestitle":"So starting from the head and moving down:", "lescontent":"1) The top back part of your head should be pointing up.."] let convertedLesson = lessonDict.toLesson() print(convertedLesson) // Lesson(title: Optional("Posture"), subtitle: Optional("Set up your body"), bgImage: Optional("Ln1"), lesImage: Optional("Posture_pic"), lesTitle: Optional("So starting from the head and moving down:"), lesContent: Optional("1) The top back part of your head should be pointing up.."))

但您必须非常确定 keys是完全相同的。

希望这会有所帮助。

如何将变量分离到其他文件和访问

1 个答案: