Swift Code Summary 4

1.swift @discardableResult Statement:

Swift Normal method If there is a return value, the call must have a receiver, otherwise the compiler will report a warning,
If you add @discardableResult to the method before you do not handle it, there will be no warning. You can also use a wildcard to receive the method return value, you can achieve the same purpose.

2. Controller initialization:

Init (urlstr:string?) {        Super.init (Nibname:nil, Bundle:nil)        if let Urlstr = urlstr {            = urlstr        }< C10/>}uiview initialization: Calling the parent class initWithFrame

3. Update the View constraint:

/// Update level Two menu constraints    Private func updatesecondcategorylayout () {        if let Tempheight = Height {            Secondcategoryview.needsupdateconstraints ()            0.25) {                            self.secondCategoryView.layoutIfNeeded ()     }}}

4. Pull up load more:

In else{return}            if self.pagenum <=               self.totalpage {                self.loaddata ()            Else  {                self.printTable.mj_ Footer.endrefreshing ()                self.printTable.mj_footer.endRefreshingWithNoMoreData ()            }        )

5.uiview.performwithoutanimation:

uiview.performwithoutanimation {                    plandiscountcollectionview.reloadsections (indexset (integer: Indexset.element (0))                }// View conversion does not perform animations, parameters are block objects, to execute the code you want to execute + (  void) Performwithoutanimation: (void (^) (void)) actionswithoutanimation

6. Decimal conversion:

if temptextcount.decimalvalue > Nsdecimalnumber (string: WaiterManager.shared.waiterPower ( Powercode.ignore)? . Powervalue). Decimalvalue {}

7. Limit TextField to enter only 3 characters:

string: String), Bool {                0        string. Count- Range.length         return 3     }

8. Variable security using the Set method private, you can adjust the method to change the value:

class hhtcomboglobaldata:nsobject {    static let shared = hhtcomboglobaldata ()      Private(setvar combomodes:[combomodel] = []        func Setcombomodel (with dicts:[ Jsondictionary]) {        combomodes.removeall ()        in            return  Combomodel ( with:dict)     }}}

9.for Loop create nine lattice:

Privatefunc setupui () {Let count:int=5Let width:cgfloat= -Let height:cgfloat= -Let bgviewwidth:cgfloat=844Let col:int=3        //spacingLet Hmargin = (Bgviewwidth-(CGFloat (COL) * width)/cgfloat ((col+1)) Let Vmargin:cgfloat= -                varRow:int =0         forIinch 0.. <Count {let Button:uibutton=UIButton () button.settitle ("Print a", for:. Normal) Button.settitlecolor (Uicolor.white, for:. Normal) Button.backgroundcolor=uicolor.redifI%col = =0{row+=1            }            varY:cgfloat =0            ifrow = =1{y= -            } Else{y= Vmargin + (height + vmargin) *cgfloat (Row)} Let X:cgfloat= Hmargin + (width + hmargin) * CGFloat (i%col) Button.frame=CGRect (x:x, Y:y, Width:width, Height:height) Bgview.addsubview (button) BottomMargin= Button.frame.maxY + -} bgheightconstraint.constant= bottommargin!    }}

Swift Code Summary 4