Yeah, the background is literally a fill using the drawing API that appears to have a z-order above the Canvas itself. So you can not draw to it, it is a privately scoped object. They call it blocker in the code, apt variable name in this case, eh? It boils down to z-orders.
for example, <Canvas id="below" /> <Canvas id="above" backgroundColor="0x00ff00" /> use the drawing API to draw into below and you will not see it. THe order in which child display objects are added to the display list defines the z-ordering. Douglas Knudsen [email protected] On Nov 16, 2010, at 3:10 PM, <[email protected]> <[email protected]> wrote: > I noticed the background color worked when I put it in the application. > However I still don’t understand why. > > I looked around container...@2844 . Do you mean the comment header above > updateDisplayList > > I really want to understand this. > > > > > > From: [email protected] [mailto:[email protected]] On Behalf Of Douglas Knudsen > Sent: Tuesday, November 16, 2010 2:36 PM > To: [email protected] > Subject: Re: [AFFUG Discuss] Very Basic code issue. > > > > check around line 2844 in Container.as and you can see why. > > > > Set no background or backgroundAlpha=0 on your drawing Canvas. Layer your > containers if you want a background color, or set it on Application in his > case. It maybe possible to add a Sprite on top of the Canvas and draw into > that too, maybe. > > > > > > Douglas Knudsen > > [email protected] > > > > > > > > On Nov 16, 2010, at 1:36 PM, Eric DeCoff wrote: > > > > > Could it be as simple as the the draw canvas having no height / width defined > ;) > > sent via droid > > On Nov 16, 2010 10:04 AM, "Darin Kohles" <[email protected]> wrote: > > also, set childCompletion="all" it's possible the canvas hasn't been fully > > rendered. You could also move the creationComplete init() to fire from the > > Canvas, instead of the Application > > > > On Tue, Nov 16, 2010 at 9:02 AM, Darin Kohles <[email protected]> wrote: > > > >> I doubt this will help, but inline styles override css styles. But since > >> clearly you are adding the graphic at runtime this shouldn't be an issue. > >> Have you tried setting the fillStyle as well (even though it's not being > >> used)? > >> > >> Also you might do graphics.clear(), before you start drawing. > >> > >> > >> On Tue, Nov 16, 2010 at 8:53 AM, Chris Morrow <[email protected]>wrote: > >> > >>> Not sure why, but I always use a nested canvas; one for the bgcolor and > >>> one for graphics and other elements. > >>> - Chris Morrow > >>> > >>> > >>> <?xml version="1.0" encoding="utf-8"?> > >>> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"; > >>> layout="absolute" creationComplete="init()"> > >>> <mx:Script> > >>> public function init():void > >>> { > >>> drawing_canvas.graphics.lineStyle(3,0xffffff, 1.0); > >>> drawing_canvas.graphics.moveTo(10,10); > >>> drawing_canvas.graphics.lineTo(100,100); > >>> } > >>> </mx:Script> > >>> <mx:Canvas width="100%" height="100%" backgroundColor="0x000000"> > >>> <mx:Canvas id="drawing_canvas" /> > >>> </mx:Canvas> > >>> </mx:Application> > >>> > >>> > >>> On Tue, Nov 16, 2010 at 9:29 AM, Atlanta Geek > >>> <[email protected]>wrote: > >>> > >>>> I have the following code and the line is not visible. If I remove > >>>> the background color from the canvas the line is visible. > >>>> Would anyone know why this is happening? I am on Flex 3.5 > >>>> > >>>> <?xml version="1.0" encoding="utf-8"?> > >>>> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"; > >>>> layout="absolute" creationComplete="init()"> > >>>> <mx:Script> > >>>> public function init():void > >>>> { > >>>> drawing_canvas.graphics.lineStyle(3,0xffffff, 1.0); > >>>> drawing_canvas.graphics.moveTo(10,10); > >>>> drawing_canvas.graphics.lineTo(100,100); > >>>> } > >>>> </mx:Script> > >>>> > >>>> <mx:Canvas id="drawing_canvas" width="100%" height="100%" > >>>> backgroundColor="0x000000" /> > >>>> </mx:Application> > >>>> > >>>> > >>>> ------------------------------------------------------------- > >>>> To unsubscribe from this list, simply email the list with unsubscribe in > >>>> the subject line > >>>> > >>>> For more info, see http://www.affug.com > >>>> Archive @ http://www.mail-archive.com/discussion%40affug.com/ > >>>> List hosted by http://www.fusionlink.com > >>>> ------------------------------------------------------------- > >>>> > >>>> > >>>> > >>> > >> > >> > >> -- > >> Darin Kohles > >> > >> > > > > > > -- > > Darin Kohles > > > > > ------------------------------------------------------------- > To unsubscribe from this list, simply email the list with unsubscribe in the > subject line > > For more info, see http://www.affug.com > Archive @ http://www.mail-archive.com/discussion%40affug.com/ > List hosted by FusionLink > -------------------------------------------------------------
