18.4.1. The scroll Property

18.4.2. The maxscroll Property

18.4.3. Typical Text-Scrolling Code

In combination, the scroll and maxscroll properties can be used to scroll a text field. This code scrolls text down one line for each click of a button:

on (press) {
  if (textField.scroll < textField.maxscroll) {
    textField.scroll++;
  }
}

And here's how we scroll text up one line with each click:

on (press) {
  if (textField.scroll > 1) {
    textField.scroll--;
  }
}

For an example of simple scroll buttons used in a movie, download the sample scrollers posted at the online Code Depot.

18.4.4. The _changed Event

1. Create an input text field on any timeline.

2. Name the text field myField.

3. On the same timeline as the text field, label a frame myField_changed.

4. Attach any code to the frame myField_changed. For example:

   trace("myField was changed");

5. Export the movie using Control Test Movie.

6. Type characters into the myField text field. The code on the frame myField_changed is executed, and "myField was changed" appears in the Output window.

Of course, the name myField is arbitrary; you can use whatever text field name you like as long as the corresponding frame label is set to the same name. Note that setting the value of a text field with ActionScript does not trigger the field's _changed event. Only user keystrokes trigger _changed.