TextFormat disappears

…when i set the textField with new text eg:

var tf = new TextField();
var myFormat = new TextFormat();

//set textField format
myFormat.color = 0xffffff;
tf.setTextFormat(myFormat);
addChild(tf)

//this will remove the text format.
tf.text = “some text”;


Any help appreciated.

Do i have to set the text format again every time it changes? If so, which event do i listen for? ie tf.addEventListener(TextEvent.CHANGE, setFormat).

thanks