> > CALayer has a mechanism built in for the sort of thing you want to do. Read > up on -[CALayer display]. You should be able to override that, or implement > the corresponding delegate method in your UIView and perform management of > your custom bitmap there. I myself do this in one app to share one bitmap > between multiple layers for example. > > The other thing worth investigating perhaps is whether CATiledLayer would > better suit your drawing needs, or if you could split your custom view up > into a series of sub-views, so you only need invalidate slices of one or two > of them. > > Mike.
That’s what I was just trying. I made a subclass of CALayer() and overrode just display() to do absolutely nothing at all, except print ‘display()’. I then made a UIView subclass which overrides layerClass() to return the type and stuck one such view randomly in my NIB. The view is made, the layer is created .. and absolutely nothing else happens. I expected to get at least ONE call to display() as the view/layer starts dirty, but I don’t get even that. I even hooked up a button to call setNeedsDisplay on the view but that didn’t prompt it either. I overrode a bunch of other methods too to print but the only one which currently gets called is init(). I expected the UIView would drive at least an initial setNeedsDisplay on the layer, and a setNeedsDisplay on the view would end up being passed-through, but it doesn’t. Calling setNeedsDisplay on the actual layer object itself seems to work, but I did sort of expect the UIView to do some things with the layer automatically. Guess I was wrong and I will need to hook all those bits up for myself. _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
