Close, but no. In Flex, parents are responsible for sizing their children. Flex Containers (which are just UIComponents with more code) do size their children, but you can also create UIComponents that know how to size their children.
Neither a container, nor a component that implements a container interface needs to be involved in any way to handle this. That is the fallacy I am addressing. Look at the example I provided and you will not see a Container or implementor of that interface. In other words: * UIComponents can contain other UIComponents. * Containers are UIComponents which know how to automatically size their children through the component lifecycle Does this make sense? Mike --- In [email protected], Joseph Balderson <[EMAIL PROTECTED]> wrote: > > In other words, UIComponents /can/ natively contain other UIComponents, > only the child UIComponent will by default have a 0 width and height. > > Which it means it won't show up on the stage. Which means, by default, > you cannot get a native (non-extended) UIComponent to show up when you > add it to another UIComponent. Which means you cannot (successfully) add > a native UIComponent to another UIComponent. > > Thanks for catching the technicality, as a writer I love that kind of > precision. > > But basically what Charlie was saying is correct: "UIComponent's can't > contain other UIComponents without being a subclass of Container or > implementing the IContainer interface." -- only he forgot to add 'and > have them successfully show up on stage'. > > So you're both correct IMO. Thanks for the clarity. > > _____________________________________________________________________ __ > > Joseph Balderson | http://joeflash.ca > Flex & Flash Platform Developer | Abobe Certified Developer & Trainer > Author, Professional Flex 3 (coming Winter 2008) > Staff Writer, Community MX | http://communitymx.com/author.cfm? cid=4674 > > > > Michael Labriola wrote: > > Guys, sorry, but that's not quite right. UIComponents can contain > > other UIComponents without being a container. It is a common use > > case. Take a look at the simple example Adobe includes with their > > docs: > > > > http://livedocs.adobe.com/flex/2/docs/wwhelp/wwhimpl/js/html/wwhelp.h > > tm?href=00001742.html > > > > You will notice that the mocal text component is a UIComponent but > > it contains a button and a text area... both UIComponents. > > > > The difference is that containers like Canvas have the logic to size > > and position any child they contain by default. UIComponent does > > not. So, in a UIComponent descendant, you need to write code to size > > and position every child or they will exist as 0 width and 0 height > > component. > > > > HTH, > > Labriola > > > > > > --- In [email protected], "Charlie Hubbard" > > <charlie.hubbard@> wrote: > >> Right. Image is a UIComponent, and TextArea is a UIComponent. > >> UIComponent's can't contain other UIComponents without being a > >> subclass of Container or implementing the IContainer interface. > > Not a > >> simple task. > >> > >> addChild() is defined in DisplayObject which apart of the Flash API > >> not the Flex API. BitmapAsset is a sublcass of DisplayObject and > > not > >> UIComponent. So you can add it to the text area directly using > > this > >> code: > >> > >> var img : BitmapAsset = new imgCls() as BitmapAsset; > >> img.x = txtArea.mouseX; > >> img.y = txtArea.mouseY; > >> txtArea.addChild( img ); > >> > >> Now, try that out, and you'll start to see some issues that you'll > >> have to asess if this is going to work for what you're trying to > > do. > >> Since the bitmap is not apart of the document in the TextArea you > > are > >> going to get clipping or scrolling. If you want to do that you'll > >> have to get really dirty with the TextArea API. Probably even > >> ditching TextArea altogether and writing your own, or modifying > > rich > >> text editor. > >> > >> Charlie > >> > >> > >> On Thu, May 29, 2008 at 5:37 PM, aarhac <aaronh@> wrote: > >>> Hello, > >>> > >>> I have figured out how to work around my problem, but I do > > wonder why > >>> one of the following methods works, and the other doesn't. I > > would be > >>> grateful if someone could explain the error in the failing > > method. > >>> The code is pasted below (Below the line of dashes) in it's > > entirety, > >>> and is commented as to which works and which doesn't. > >>> > >>> The image referenced in this case is a 32x32 pixel png file on my > >>> local system. I am attempting to display the image "on" a text > > area. > >>> Using the default example from the flex documentation to embed an > >>> image, I cannot get the image to show up when added to the text > > area's > >>> display list, but it does show just fine when added to the root > >>> display list. I also added the image to the textArea using > >>> addChildAt(txtIcon, txtArea.numChildren) with no change in > > effect. > >>> The second method works just fine. I imagine that the problem has > >>> something to do with applying the image as a byte array to > >>> image.source, but I wonder why exactly? Is this a bug? > >>> > >>> Thanks in advance, > >>> > >>> --Aaron > >>> > >>> ------------------------------------ > >>> > >>> <?xml version="1.0" encoding="utf-8"?> > >>> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"; > >>> layout="absolute"> > >>> > >>> <!--Works--> > >>> <mx:Image id="txtIcon" source="@Embed(source='c:/icon.png')"/> > >>> > >>> <mx:TextArea id="txtArea" width="400" height="200" > > click="addImage()"/> > >>> <mx:Script> > >>> <![CDATA[ > >>> import mx.controls.Image; > >>> import mx.core.BitmapAsset; > >>> > >>> // Doesn't work > >>> [Embed(source="c:/icon.png")] > >>> [Bindable] > >>> public var imgCls:Class; > >>> > >>> public function addImage():void > >>> { > >>> // Doesn't work > >>> var loadedImg:Image = new Image(); > >>> loadedImg.source = new imgCls() as BitmapAsset; > >>> > >>> loadedImg.x = 10; > >>> loadedImg.y = 10; > >>> txtArea.addChild(loadedImg); > >>> > >>> // Note: While the above doesn't work, adding the > >>> // image to the root display list does work: > >>> //addChild(loadedImg); > >>> > >>> // Works > >>> txtIcon.x = 50; > >>> txtIcon.y = 10; > >>> txtArea.addChild(txtIcon); > >>> } > >>> ]]> > >>> </mx:Script> > >>> > >>> </mx:Application> > >>> > >>> > > > > > > > > ------------------------------------ > > > > -- > > Flexcoders Mailing List > > FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt > > Search Archives: http://www.mail-archive.com/flexcoders% 40yahoogroups.comYahoo! 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