Question

How do you determine the line height (in pixels) of the text in a Spark Label?

Answer 1

keyle’s answer will only give you the height of the text, not the actual ‘lineHeight’ style. You can easily get that style like this:

myLabel.getStyle("lineHeight");

The problem is that this can return a relative value (a percentage) or an absolute value (in pixels). The default – if no lineHeight was explicitely set – is "120%".

So here’s how we can get the value in pixels in both cases:

var lineHeightStyle:* = myLabel.getStyle("lineHeight");

//its already a value in pixels
if (lineHeightStyle is Number) var lineHeight:Number = lineHeightStyle;
//it's a relative value: let's calculate
else {
    var lineMetrics:TextLineMetrics = myLabel.measureText(myLabel.text);
    //get the numeric value from the string and divide it by 100
    var ratio:Number = int(lineHeightStyle.match(/\d+/)[0]) / 100;
    lineHeight = lineMetrics.height * ratio;
}