Make it easier to use iframeDialog

[alfonsoml]

Currently is not too easy to use the iframeDialog, specially the part about getting the current editor or listening to the dialog events.

The few resources available show The proposal here is to ignore the CKEDITOR.dialog.addIframe and do that work again ​http://cksource.com/forums/viewtopic.php?f=11&t=16040 This page explains the basic usage, but again, it seems that it's extra work ​http://www.tommed.co.uk/?p=31

My proposal is to make the CKEDITOR.dialog.addIframe create automatically a function that will notify the inner window of the dialog events (load, ok and cancel), so the only requirement to specify a dialog are two lines, almost like any other dialog:

editor.addCommand( 'myPlugin', new CKEDITOR.dialogCommand( 'myPlugin' ) );
CKEDITOR.dialog.addIframe( 'myPlugin', "Plugin title", this.path + 'popup.html', 700, 470);

And adding a simple function in the iframe:

// Gets notified of events in the main dialog
function onDialogEvent( e )
{
	switch(e.name)
	{
		case 'load':
			oEditor = e.editor;
			init();
			break;

		case 'ok':
			Ok();
			break;

		case 'cancel':
			break;
	}
}

The patch also includes the #5745 proposal so that way it's possible to alter the default buttons or other behavior in the dialog definition.

[alfonsoml]

Proposed patch

[garry.yao]

The proposal is a good move, while I wonder if it the level of flexibility is really enough, e.g. it's still impossible to manipulate other dialog fields from within the iframe, I think it's better to just pass in the "dialog" reference, leaving other options to the end developers.

[garry.yao]

Another important usability issue is #5541, which is right not working for defined "height".

[alfonsoml]

This ticket is about iframeDialogs (all the content is a single iframe), not about a normal dialog where there are several elements and one of them is an iframe.

[garry.yao]

Ok, plus the fixing of #5541.

[alfonsoml]

Fixed with [6677]