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Groups > comp.lang.java.programmer > #35058
| From | Eric Sosman <esosman@comcast-dot-net.invalid> |
|---|---|
| Newsgroups | comp.lang.java.programmer |
| Subject | Re: What do you think of my CropImage class |
| Date | 2016-07-21 12:56 -0400 |
| Organization | A noiseless patient Spider |
| Message-ID | <nmqusg$mf5$1@dont-email.me> (permalink) |
| References | <87twfk93vu.fsf@Equus.decebal.nl> <8737n36ucx.fsf@Equus.decebal.nl> <nmqj30$boh$1@dont-email.me> <87lh0v560n.fsf@Equus.decebal.nl> |
On 7/21/2016 12:07 PM, Cecil Westerhof wrote:
> On Thursday 21 Jul 2016 15:35 CEST, Eric Sosman wrote:
> [...]
>> - It constructs a pair of JLabels on whatever thread loads and
>> initializes the class. (And the JLabels are static, which is so
>> very odd as to be downright weird. Have you thought this through?)
> [...]
> But about the things being static. There is always exactly one, so
> what is the problem with things being static? If it is a real no-no I
> could change it.
There's a containment hierarchy of displayed things: You start
with a top-level container (JFrame, JDialog, ...) that contains lower-
level sub-components (JPanels, JTrees, ...) that in turn contain
still lower-level components (JButtons, more JPanels, ...). That
is, components are nested in a tree.
It follows that a given component can appear at only one spot
in the tree: It is contained in exactly one container, or is a
top-level component that is not contained at all. This way, the
contained component can have (for example) *a* position relative
to its container, instead of a whole Map of "I'm *here* in this
container, *there* in that container, ..." (Swing might have
required a container to maintain a list of contained objects *and*
their positions and sizes, but it didn't; positions and sizes and
so on are attributes of the contained objects.)
To maintain tree-ness, when you add a component to a container
Swing automatically removes it from any container it already belonged
to. So, if you have a static JLabel and you add it to one CropImage
instance, it cannot simultaneously appear in another CropImage: It
can be in one or the other (or neither), but not in both. Since
you're probably anticipating only one CropImage instance this may
not seem a big deal, may not even *be* a big deal (were it not for
the EDT issue), but it's certainly weird.
--
esosman@comcast-dot-net.invalid
"Don't be afraid of work. Make work afraid of you." -- TLM
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What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-20 09:15 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-20 11:12 +0200
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-20 10:02 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-20 21:14 +0200
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-20 12:50 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 12:11 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 14:19 +0200
Re: What do you think of my CropImage class Qu0ll <qu0ll64@gmail.com> - 2016-07-21 05:53 +1000
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-20 13:46 -0700
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-20 13:59 -0700
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-20 15:40 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 12:27 +0200
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-21 05:17 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 17:43 +0200
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-21 08:59 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 19:10 +0200
Re: What do you think of my CropImage class Arne Vajhøj <arne@vajhoej.dk> - 2016-07-23 21:47 -0400
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-25 04:51 -0700
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-25 15:01 -0700
Re: What do you think of my CropImage class Arne Vajhøj <arne@vajhoej.dk> - 2016-07-25 21:06 -0400
Re: What do you think of my CropImage class Arne Vajhøj <arne@vajhoej.dk> - 2016-07-25 21:09 -0400
Re: What do you think of my CropImage class Nigel Wade <nmw@local.domain> - 2016-07-21 15:44 +0100
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 17:46 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 12:25 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 14:16 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 12:05 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 13:23 +0200
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-21 07:58 -0700
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 11:13 -0400
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 18:12 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 17:49 +0200
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 11:58 +0200
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 09:35 -0400
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-21 09:03 -0700
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 12:39 -0400
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 18:07 +0200
Re: What do you think of my CropImage class Nigel Wade <nmw@local.domain> - 2016-07-21 17:23 +0100
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 12:56 -0400
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 19:03 +0200
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-21 10:25 -0700
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 14:24 -0400
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-21 11:54 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 20:25 +0200
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 15:37 -0400
Re: What do you think of my CropImage class Martin Gregorie <martin@address-in-sig.invalid> - 2016-07-21 21:30 +0000
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 23:52 +0200
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 20:35 -0400
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-22 04:21 +0200
Re: What do you think of my CropImage class Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-07-21 22:44 -0400
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-22 10:27 +0200
Re: What do you think of my CropImage class Martin Gregorie <martin@address-in-sig.invalid> - 2016-07-22 10:47 +0000
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-22 05:16 -0700
Re: What do you think of my CropImage class Nigel Wade <nmw@local.domain> - 2016-07-22 15:10 +0100
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-22 07:47 -0700
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-22 10:21 -0700
Re: What do you think of my CropImage class Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-07-21 08:30 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 18:19 +0200
Re: What do you think of my CropImage class Eric Douglas <e.d.programmer@gmail.com> - 2016-07-21 10:18 -0700
Re: What do you think of my CropImage class Cecil Westerhof <Cecil@decebal.nl> - 2016-07-21 20:12 +0200
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