TextField - Max Length and Event Handling

gistfile1.txt

var win = Ti.UI.createWindow({layout: 'vertical', backgroundColor:'#fff'});

var textField = Ti.UI.createTextField({
	height: Ti.UI.SIZE,
	width: '90%',
	font: {fontSize: 20},
	softKeyboardOnFocus: Ti.UI.Android.SOFT_KEYBOARD_SHOW_ON_FOCUS
});

textField.addEventListener('return', function(e){
	Ti.API.info('RETURN EVENT');
	if(e.source.value.length > 5) {
		alert('Max Length can not exceed five characters');
		e.source.value = e.source.value.substring(0,5);
		e.source.focus();
	}
});

textField.addEventListener('change', function(e){
	if(isNaN(e.value)) {
		alert('Only Numbers Please')
	}
});

win.add(textField);

win.open();