How to create underlined UITextField

问题

iOS noob here

When I add a default UITextField to the ViewController, it looks like this:

My designer would like me to make the UITextField look like this (i.e. background is transparent, and just has an underline:

How do I do this? Should be asking my designer for an image to set as background for the UITextField. What should the image look like? Should the image be = the blue background + the underline (minus the number i guess)

Is that right?

UPDATE: Based on direction below (from @Ashish Kakkad), added this code in Swift to ViewDidLoad:

    var bottomLine = CALayer()
    bottomLine.frame = CGRectMake(0.0, view.frame.height - 1, view.frame.width, 1.0)
    bottomLine.backgroundColor = UIColor.whiteColor().CGColor
    tf_editPassword.borderStyle = UITextBorderStyle.None
    tf_editPassword.layer.addSublayer(bottomLine)

This almost works, but the problem is that all side borders disappear, I want just the bottom line to stay.

回答1:

@Ashish Kakkad has posted the right code but the reason it might not be working for @user1406716 is because when there is no text in the textfield, the height and width of the frame are 0 so maybe you can try the following :

Obj-C :

CALayer *bottomLine = [CALayer layer];
bottomLine.frame = CGRectMake(0.0f, 75 - 1, 300, 1.0f);
bottomLine.backgroundColor = [UIColor whiteColor].CGColor;
[myTextField setBorderStyle:UITextBorderStyleNone];
[myTextField.layer addSublayer:bottomLine];

Swift :

var bottomLine = CALayer()
bottomLine.frame = CGRectMake(0.0, 75 - 1, 300, 1.0)
bottomLine.backgroundColor = UIColor.whiteColor().CGColor
myTextField.borderStyle = UITextBorderStyle.None
myTextField.layer.addSublayer(bottomLine)

This will ensure that the line is visible even when there is no text in the textfield.

回答2:

Try this code :

Obj-C

CALayer *bottomLine = [CALayer layer];
bottomLine.frame = CGRectMake(0.0f, self.frame.size.height - 1, self.frame.size.width, 1.0f);
bottomLine.backgroundColor = [UIColor whiteColor].CGColor;
[myTextField setBorderStyle:UITextBorderStyleNone];
[myTextField.layer addSublayer:bottomLine];

Swift

var bottomLine = CALayer()
bottomLine.frame = CGRectMake(0.0, view.frame.height - 1, view.frame.width, 1.0)
bottomLine.backgroundColor = UIColor.whiteColor().CGColor
myTextField.borderStyle = UITextBorderStyle.None
myTextField.layer.addSublayer(bottomLine)

Hope it helps

If you are using the auto-layout then try to do this code inside the viewDidLayoutSubviews method.

回答3:

To update this with Swift 3:

let bottomLine = CALayer()
bottomLine.frame = CGRect(origin: CGPoint(x: 0, y:first.frame.height - 1), size: CGSize(width: first.frame.width, height:  1))
bottomLine.backgroundColor = UIColor.white.cgColor
first.borderStyle = UITextBorderStyle.none
first.layer.addSublayer(bottomLine)

来源：https://stackoverflow.com/questions/30701655/how-to-create-underlined-uitextfield

标签

ios

swift

storyboard

uitextfield