Alexandre
I now understand one of your problems, you need to give the handler a
reference to the control, but the control does not exist yet since
you're actually creating it. Giving the handler a fake control, of the
form {map: map} (where map is the map instance) should do the trick.
I think handlers do not actually require a reference to the control,
they just need a reference to the map (to register listeners). So I
don't understand why we have this constraint. Anyone involved in the
design of handlers knows?
On Tuesday, July 21, 2009, Alexandre Dube <ad...@mapgears.com> wrote:
> Hi,
>
> I'm trying to reproduce what we discuss. I'm not really familiar with this
> method and I'm having difficulties with 'this'. Here's what I have so far :
>
> /*** START ***/
> var delCtrl = new OpenLayers.Control({
> layer: olWFSRoads,
> handlers: {"keyboard": new OpenLayers.Handler.Keyboard(this,{ //
> <------- 'this' is not the control
> keydown: function(evt) {
> var code = evt.keyCode;
> //var features = this.layer.selectedFeatures; // <------- this is
> not the control, and so on...
> var features = olWFSRoads.selectedFeatures; // <----- can we avoid
> the use of olWFSRoads ?
>
> if(code == OpenLayers.Event.KEY_DELETE && features.length > 0 &&
> this.confirmDelete() ) {
> this.deleteFeatures(features);
> return;
> }
> }
> })},
> controls: [
> new OpenLayers.Control.SelectFeature(
> olWFSRoads, {
> onSelect: function(f) {
> f.state = OpenLayers.State.DELETE;
> this.layer.drawFeature(f);
> }
> })
> ],
> confirmDelete: function() {
> return (confirm("Delete selected features ?"))
> },
> deleteFeatures: function(features) {
> this.layer.destroyFeatures(features);
> }
> });
> /*** END ***/
>
> I made the discussed changes to the OL.Control to be able to automatize
> activation/deactivation/setMap.
>
> If you look at the <---------- arrow, you'll see a 'this', which is supposed
> to be the control, owner of the handler. Well, that 'this' is not the
> control, it's the html page (figures). I tried to put 'delCtrl' instead but
> it didn't work. I really wonder how I am supposed to create controls that
> way (without creating a class) and use the 'this' (or something else).
>
> Any hint would be greatly appreciated,
>
> Alexandre
>
> P.S. Also, I believe it's ok to have my 'user' functions, like confirmDelete
> directly inside the control since the control is completely custom-made (i.e.
> not using events).
>
> Alexandre Dube wrote:
>
> Eric Lemoine wrote:
>
>
> so, to get to the delete control you've been working on, I see more
> value, in terms of flexibility, in adding "control composition" to the
> control base class.
>
>
>
>
>
> I also agree. Originally, the control had a Feature handler instead of a
> SelectFeature control. Looking at it now, it's too simple to be justified as
> a new control.
>
>
>
> About the 'controls' property and the act./dea. automatism : that's a good
> idea, but wouldn't it be good to have a 'handlers' property also and
> activate/deactivate all handlers as well ? Currently, control has a
> 'handler' property only. Would it make sense to have 'handlers' added a do
> the same kind of automatism as the new 'controls' property ?
>
>
> Agreed.
>
>
>
>
> Great.
>
>
>
>
>
>
> --
> Alexandre Dubé
> Mapgears
> www.mapgears.com
>
>
--
Eric Lemoine
Camptocamp France SAS
Savoie Technolac, BP 352
73377 Le Bourget du Lac, Cedex
Tel : 00 33 4 79 44 44 96
Mail : eric.lemo...@camptocamp.com
http://www.camptocamp.com
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