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Question

I am making a app without using storyboard. The app has a long text so I can't get enought space on one line. The app is for both iPad and iPhone. The adjustSizeToFit = true does not work, is there a metode to adjust size of label with multiple lines?

Answer 1

There is no property on UILabel called adjustSizeToFit . Are you sure you didn't mean adjustsFontSizeToFitWidth ? Which if you look at the documentation, says:

Normally, the label text is drawn with the font you specify in the font property. If this property is set to true, however, and the text in the text property exceeds the label's bounding rectangle, the receiver starts reducing the font size until the string fits or the minimum font size is reached. In iOS 6 and earlier, this property is effective only when the numberOfLines property is set to 1.

Which I'm not sure is what you wanted.

If you wanted a UILabel with an arbitrary number of lines, where the text is contained within a certain width, continue reading:

What you do will depend on whether you're using AutoLayout or not:

Not AutoLayout

Just use:

let size = label.sizeThatFits(CGSize(width: myWidth, height: CGFloat.max))
// CGFloat.max, because we don't want to limit the UILabel's height.
label.frame.size = size

AutoLayout

Firstly, you should set numberOfLines to zero. Secondly, you need to tell AutoLayout how long each line can be, this doesn't default to the width of the label. For this you need a UILabel subclass:

class myLabel : UILabel {
    override func layoutSubviews() {
        // 1. Get the label to set its frame correctly:
        super.layoutSubviews()

        // 2. Now the frame is set we can get the correct width 
        // and set it to the preferredMaxLayoutWidth.
        self.preferredMaxLayoutWidth = self.frame.width
    }
}