"Swift Learning Notes" page jump condition judgment and pass value

Before jumping the page we may decide whether to enter the correct data, as shown, if there is no data input pop-up prompt, do not jump.

One: page Jump

1. On the first page, put a label on a TextField and a button

2. Put two labels and a button on the second form, and specify a Viewcontroller

3. Create a Segue connection two forms, open mode Select Modal, and give Segue "OpenView"

3. On page 1, create a reference to the input text box and click Action on the button

Determine if the text has data in action, and if not, open a new form if there is one

@IBAction func Passnametoview (sender:anyobject) {guard Let text= Tename.textwhere!text.isemptyElse{let title="Warning"Let message="Please enter name!"Let oktext="Ok"Let alert=Uialertcontroller (Title:title, Message:message, PreferredStyle:UIAlertControllerStyle.Alert) let Okbut Ton=uialertaction (Title:oktext, style:. Cancel, Handler:nil) alert.addaction (okbutton) Presentviewcontroller (Alert, animated:true, Completion:nil)return; } self.performseguewithidentifier ("OpenView", Sender:self)//or if let text = Tename.text where!text.isempty}

This allows you to open a new form.

4. Returning the original form from the new form

The button in page 2 creates an action code as follows

    @IBAction func backtoparent (sender:anyobject) {        self.dismissviewcontrolleranimated (True  , Completion:nil)    }

Two. Page Pass value

1. In page 2, declare a string variable to receive the transmitted information and a lable reference, displayed in the label after the form is loaded

@IBOutlet weak var receivename:uilabel!         ""    Override func viewdidload () {        super.viewdidload ()        // Do any additional setup after loading The view. = receivedstr    }                 

2. Page 1 override the Prepareforsegue method to pass value input values to page 2

override func Prepareforsegue (Segue:uistoryboardsegue, sender:anyobject?) {        if'openView'  {            if'?  Secondviewcontroller {                = tename.text!            }     }}

OK the whole process is complete.

Full code: Judging condition page jumps. zip

"Swift Learning Notes" page jump condition judgment and pass value