Adds the listener to the collection of listeners who will be
notified when a progress is made during the loading of the current
URL or when the loading of the current URL has been completed.
@param listener the listener which should be notified
@exception IllegalArgumentException <ul>
<li>ERROR_NULL_ARGUMENT - if the listener is null</li>
</ul>
@exception SWTException <ul>
<li>ERROR_THREAD_INVALID_ACCESS when called from the wrong thread</li>
<li>ERROR_WIDGET_DISPOSED when the widget has been disposed</li>
</ul>
Adds the listener to the collection of listeners who will be notified when a progress is made during the loading of the current URL or when the loading of the current URL has been completed.
@param listener the listener which should be notified
@exception IllegalArgumentException <ul> <li>ERROR_NULL_ARGUMENT - if the listener is null</li> </ul>
@exception SWTException <ul> <li>ERROR_THREAD_INVALID_ACCESS when called from the wrong thread</li> <li>ERROR_WIDGET_DISPOSED when the widget has been disposed</li> </ul>
@since 3.0