What is a good way to visualize a large as3 project? - actionscript-3

I've build a fairly large system in as3 and now I need to introduce some other programmers in the different parts, and hopfully they will eventually grasp the entire system.
I need to describe relations between classes and maybe some kind of flow, but the relations are the most important.
I've checked UML but I find it a bit strict and would like to be able to write comments about specific classes or relations and maybe be able to draw curved lines/arrows etc. In UML I also find it hard to know which kind of lines/arrows to use when and where.
So I am looking for a method/software/tutorial on this topic, either on some extended/simplified UML or a completely different method.
Any ideas are welcome!

I would recommend Crocus Modeller UML for AS3 & Flex. You can import your code and create cute diagram (explaining it to other people is then a joy). Also, there are some tips reminding you very quickly UML relations.

Related

How do I document my code to understand how it flows (works)?

I am writing a small game,and I now have 9 C# scripts that make it work. I have lost track of what exactly is happening and how. I want to know how things work from the moment the game starts. Whats happening and how, etc.
I am a beginner, and I have heard that writing down your program flow is called documenting it. How can I document? Do I have to write comments everywhere in my code to explain the flow of the program?
Putting extensive comments into your code is not a good approach. Basically you should try to make your code as self-explanatory as possible. You do this by carefully planning what belongs into a class or function and by using meaningful names for your classes, functions and variables. Comments are nothing but a last resort if additional explanation is really required.
In most cases you should also also have some documents in addition to the code that explain certain aspects of your software:
Requirements document - what is the purpose of the software, how is it used
Architecture and design specification - what are the modules and classes of the software and how do they interact. Often this document mainly consists of one or more diagrams (UML or something else).
Build manual - how to compile and link the software
Installation instructions
User manual
This list is neither complete nor is it mandatory. If, for example, the user interface of your software is simple and self-explaining, you probably won't need a user manual.
Sometimes diagrams make better documentation than text. There is a standard way of diagramming a control flow (whether it's of a program or a business process). They're called ... wait for it ... control-flow diagrams. But I don't think that's exactly what you're after.
There are also flow charts (often spelled as one word), which may be more suited to software than general control-flow diagrams. Flow charts can be useful for understanding an algorithm, but they generally don't give a good big-picture view.
With a complicated program, what might be more important to keep in mind is the data flow. For those we have ... can you guess? ... data-flow diagrams (DFDs).
DFDs can be drawn at varying levels of detail. You can have a high-level one that shows the major components of the system and how they fit together and low-level ones that show the nitty-gritty details for the portions of the system that require more detail.
DFDs can be used for a variety of analyses, including things like threat modeling. But I find them great for getting an overview of what's-what when I'm looking at a new project (or one I've forgotten about). You should be able to find some tutorials about DFDs online, and I think some drawing software (like Visio) have templates specifically for DFDs (and probably the other types of diagrams I've mentioned).
Some might consider DFDs a bit old-school and prefer more rigorous systems like UML (Unified Modeling Language), which is capable of expressing many more concepts and of having a very direct mapping between your "model" and your code. I've never learned enough UML to get much use out of it. The diagrams in many books on software patterns are expressed in UML.

Class Diagrams - questionably useful?

How is a class diagram actually any different to just looking at the class definition with all the functions collapsed? I've been asked to write some and realized that this is all just .. read the source .. it has comments. What's the point of a class diagram, how is it different to even minorly commented definitions, and what makes a good class diagram better than others?
Edit: Yes, the source already exists, and did so long before the class diagrams.
Another edit: People have been talking about visual vs textual tastes. That's not the definition of class diagram I was given. It's still purely textual. The sample class diagram is a bunch of text, that resembles the source code with the function definitions cut. That's the reason that I asked. If it was a genuine diagram, I could understand.
If you have one or two classes, that does not make a diference.
If you have a complex object model, things change.
And, at least for me, is easy to look first at a diagram in order to look for what I want in stead of looking at a bunch of source files.
Also seeing the classes on a picture and their relations helps to understant the ideas of the project.
I'd rather have source. Given that, I can always reverse engineer it.
You have to ask what UML is for: it's just a communication device, a way to get your ideas across to other developers. If UML is helping, great. If it becomes another burden to maintain, prefer working code with good unit tests.
A good class diagram clearly shows each classes responsibilies and associations - at an appropriate level of abstraction.
Class diagrams are useful because they allow you to design at a higher level of granularity. Operations drawn on a white board are easier to change than source code. It also clearly shows associations through lines, rather than leafing through code.
They're helpful in that they are a segue from conceptual ideas to source code.
They let you say more with less.
If the source already exists, I guess it's the old adage, "A picture tells a thousand words".
For someone not familiar with the source, a diagram may help them to grok the overall design quicker then reading the source, no matter how well documented. Some people are more visual than others. Personally, I'd rather have the source.
Like many things, it's probably a matter of taste.
Edit:
I thought the definition of a diagram was that it is visual. However, if it's just a bunch of text, then the only point I can see is that it provides an overview of intent without the unnecessary implementation details.
The difference between looking at a diagram and the source is that you don't need to process as much data when looking at the diagram (a picture) than when reading the source (says thousand words).
In my experience I've found class diagrams to be very useful when I'm not familiar with the architecture of the software. But class diagrams don't replace the need for source code and proper documentation, they're just a communication and productivity tool that complement the methods I mentioned before. Their intent is to understand the software architecture. not to replace other documentations. How useful a class diagram is depends on its quality and the complexity of it and the source code.
Don't put too much detail into the diagrams. It makes them confusing. You'll want them to communicate relationships, not API and a list of methods.
They also help to see when and where to refactor code. Use class diagrams along with proper documentation and you'll be all set.
I'm not sure quite what definition you've been given for a Class Diagram - it sounds almost as though the example you've been shown has just one class on it. If so, I can understand why you think it's a bit ridiculous.
Class Diagrams are a way to show the relationships between classes - a good one can provide a lot of information about how your system works in one diagram that rewards careful study. It allows a developer unfamiliar with a subsystem to come up to speed quickly without getting mired in the implementation details.
Here's one simple one I found with a quick Google:
http://netbeans.org/images_www/articles/uml-class-diagram/Completed-Class-Diagram.gif
Some tools (Microsoft's Visual Studio is one) contain tools that allow you to draw a class diagram once and have it automatically kept up to date ("in synch") with the code. Very useful.

This Question about how do i learn from basic As3 to advanced as3

This Question about how do i learn from basic As3 to advanced as3 , as i want to become professional in as3.And work as freelancer.
can anybody guide me how to reach to the peak of Action-Script-3.
This question seems to be really funny to many but this is the most basic question in my mind
1) which way to go.
2) what steps i should follow.
3) how should i do my first project professionally.
4) how do i become excellent in as3
I believe actionscript 3.0 and Flash in general allows you work on a wide variety of projects:
from interactive rich media web interfaces, to interactive video, animation, games, desktop applications, rich internet applications, physical installations, creative and abstract pieces, etc.
It's up to you what you want to do, but I'm guessing if you start with something that motivates you, something that you enjoy working on and learning, it's a sure way forward
and it will make the boring bits more fun, and that's what it should be about: FUN!
It doesn't matter if it's actionscript or something else you want to learn, enjoy learning/challenging yourself and you'll get there faster than you think.
Answer 1.):
With regards to actionscript, based on what you want to do with it, there are a couple of good starts. Let's say you're interested in just the code, not planning to use the Flash IDE much or at all, and your aim to develop great applications. as #David Morrow said, Colin Moock's Essential Actionscript 3.0 is great. Also his guide From the Ground Up is a compressed version of the book.
An easier lecture, but packed with hands-on tips to getting things done in actionscript 3.0 is Rich Shupe's Learning Actionscript 3.0, also from O'Reilly. This might help you get up to speed with project you might have in mind.
Answer 2.) and 3.):
In short you have at least two routes:
easy/practical start where you learn
by doing small mini projects, but
keep in mind there are gaps to fill
in order to move on to complex
projects
a 'harder'/more theory based start,
that will cover advanced topics, so
you will ready to take most projects
out there, simple or complex.
Answer 4.):
It also important to keep in mind that there is no substitute for experience! Learn how ever it feels comfortable, but plan time for practicing/writing a lot of code/failing/fixing/repeating. Don't worry about getting things wrong! I don't know any programmer that can write a complex project perfectly from start to finish. Basically all projects out there are the result of this loops of failing/fixing/learning/ if you want to put it this way.
Never be afraid of getting things wrong ! You learn more this way, than getting things right, but not fully understanding why, also, you can discover something new. You can't run
into happy accidents if you don't have accidents at all.
As you progress you will like some things more than others. It is important to try everything when you learn. Knowing what you don't like is just as important as knowing what you like. Don't take everything for granted and form your opinions while learning.
You mentioned peaks. It's great to aim high. As I mentioned earlier, actionscript can be used for so many things, that it's hard to be the best in all areas. Andre Michelle and Joa Ebert for example are very talented developers and have a lot of experience with sound. Chris Georgenes on the other hand is a very talented animator. I wouldn't expect roles to swap anytime soon. If it helps, choose people that are actionscript virtuosos, get inspired by their works, there are plenty of them out there.
HTH,
George
understand OOP classes and packages.
Inheritance and polymorphism
keep all content in external xml files
dont ever put any code in your fla
start building a library of reusable classes for common tasks ( a util library )
start working with the Essential Actionscript 3.0 and you are on your way...
read and understand this entire book and you will be rolling
The simplest, yet probably most important answer is: Use it.
The only way you'll become advanced in AS3 (or any language) is to just start using it. Do some experiments, maybe create some small tools for yourself, or find an open source app and start contributing to it.
Books will help, but they're no substitute for actual experience using the language.
As they say, you need to learn to crawl before you can walk.
You need a solid understanding of programming. See David Morrow's answer for things you should know. Also add to the list a knowledge of datastructures.
Start programming. As George Profenza said, start with a simple project first and something that you will enjoy doing. If you undertake something too big you may end up disillusioned. The best thing about working on little things often is that you will encounter certain problems, and you will learn through experience on how to tackle them.
Once you have the basic hang of things start looking at other people's source code. Visit blogs of various well known flash developers and go through their code. Learn from the best. My blogrole is a list of such people.
After a while, maybe a year or so you will be a decent AS3 programmer. Remember AS3 is just a tool. What seperates the men from the boys is being able to solve problems. Start tackling more complex problems, for example, develop a voxel engine or something along those lines. The best programmers tend to experiment with problems in the field of computer science. In doing so, they become knowledgable on various things like 3D rendering, Audio etc and develop unique skills placing them on the cutting edge.
Well I'm a visual programmer, i only learn as a means to an end - I want to make things.
If you are as i am - then here's what I recommend to go from basic AS3 to advanced AS3.
Make a game. OR, and this might be an even better route.
Clone a game that you like - e.g. tetris, bomberman, pacman
I know it a single statement answer.... not fancy, but - you will HAVE to learn so much in the process of creating it.

How do you plan an application's architecture before writing any code? [closed]

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One thing I struggle with is planning an application's architecture before writing any code.
I don't mean gathering requirements to narrow in on what the application needs to do, but rather effectively thinking about a good way to lay out the overall class, data and flow structures, and iterating those thoughts so that I have a credible plan of action in mind before even opening the IDE. At the moment it is all to easy to just open the IDE, create a blank project, start writing bits and bobs and let the design 'grow out' from there.
I gather UML is one way to do this but I have no experience with it so it seems kind of nebulous.
How do you plan an application's architecture before writing any code? If UML is the way to go, can you recommend a concise and practical introduction for a developer of smallish applications?
I appreciate your input.
I consider the following:
what the system is supposed to do, that is, what is the problem that the system is trying to solve
who is the customer and what are their wishes
what the system has to integrate with
are there any legacy aspects that need to be considered
what are the user interractions
etc...
Then I start looking at the system as a black box and:
what are the interactions that need to happen with that black box
what are the behaviours that need to happen inside the black box, i.e. what needs to happen to those interactions for the black box to exhibit the desired behaviour at a higher level, e.g. receive and process incoming messages from a reservation system, update a database etc.
Then this will start to give you a view of the system that consists of various internal black boxes, each of which can be broken down further in the same manner.
UML is very good to represent such behaviour. You can describe most systems just using two of the many components of UML, namely:
class diagrams, and
sequence diagrams.
You may need activity diagrams as well if there is any parallelism in the behaviour that needs to be described.
A good resource for learning UML is Martin Fowler's excellent book "UML Distilled" (Amazon link - sanitised for the script kiddie link nazis out there (-: ). This book gives you a quick look at the essential parts of each of the components of UML.
Oh. What I've described is pretty much Ivar Jacobson's approach. Jacobson is one of the Three Amigos of OO. In fact UML was initially developed by the other two persons that form the Three Amigos, Grady Booch and Jim Rumbaugh
I really find that a first-off of writing on paper or whiteboard is really crucial. Then move to UML if you want, but nothing beats the flexibility of just drawing it by hand at first.
You should definitely take a look at Steve McConnell's Code Complete-
and especially at his giveaway chapter on "Design in Construction"
You can download it from his website:
http://cc2e.com/File.ashx?cid=336
If you're developing for .NET, Microsoft have just published (as a free e-book!) the Application Architecture Guide 2.0b1. It provides loads of really good information about planning your architecture before writing any code.
If you were desperate I expect you could use large chunks of it for non-.NET-based architectures.
I'll preface this by saying that I do mostly web development where much of the architecture is already decided in advance (WebForms, now MVC) and most of my projects are reasonably small, one-person efforts that take less than a year. I also know going in that I'll have an ORM and DAL to handle my business object and data interaction, respectively. Recently, I've switched to using LINQ for this, so much of the "design" becomes database design and mapping via the DBML designer.
Typically, I work in a TDD (test driven development) manner. I don't spend a lot of time up front working on architectural or design details. I do gather the overall interaction of the user with the application via stories. I use the stories to work out the interaction design and discover the major components of the application. I do a lot of whiteboarding during this process with the customer -- sometimes capturing details with a digital camera if they seem important enough to keep in diagram form. Mainly my stories get captured in story form in a wiki. Eventually, the stories get organized into releases and iterations.
By this time I usually have a pretty good idea of the architecture. If it's complicated or there are unusual bits -- things that differ from my normal practices -- or I'm working with someone else (not typical), I'll diagram things (again on a whiteboard). The same is true of complicated interactions -- I may design the page layout and flow on a whiteboard, keeping it (or capturing via camera) until I'm done with that section. Once I have a general idea of where I'm going and what needs to be done first, I'll start writing tests for the first stories. Usually, this goes like: "Okay, to do that I'll need these classes. I'll start with this one and it needs to do this." Then I start merrily TDDing along and the architecture/design grows from the needs of the application.
Periodically, I'll find myself wanting to write some bits of code over again or think "this really smells" and I'll refactor my design to remove duplication or replace the smelly bits with something more elegant. Mostly, I'm concerned with getting the functionality down while following good design principles. I find that using known patterns and paying attention to good principles as you go along works out pretty well.
http://dn.codegear.com/article/31863
I use UML, and find that guide pretty useful and easy to read. Let me know if you need something different.
UML is a notation. It is a way of recording your design, but not (in my opinion) of doing a design. If you need to write things down, I would recommend UML, though, not because it's the "best" but because it is a standard which others probably already know how to read, and it beats inventing your own "standard".
I think the best introduction to UML is still UML Distilled, by Martin Fowler, because it's concise, gives pratical guidance on where to use it, and makes it clear you don't have to buy into the whole UML/RUP story for it to be useful
Doing design is hard.It can't really be captured in one StackOverflow answer. Unfortunately, my design skills, such as they are, have evolved over the years and so I don't have one source I can refer you to.
However, one model I have found useful is robustness analysis (google for it, but there's an intro here). If you have your use-cases for what the system should do, a domain model of what things are involved, then I've found robustness analysis a useful tool in connecting the two and working out what the key components of the system need to be.
But the best advice is read widely, think hard, and practice. It's not a purely teachable skill, you've got to actually do it.
I'm not smart enough to plan ahead more than a little. When I do plan ahead, my plans always come out wrong, but now I've spend n days on bad plans. My limit seems to be about 15 minutes on the whiteboard.
Basically, I do as little work as I can to find out whether I'm headed in the right direction.
I look at my design for critical questions: when A does B to C, will it be fast enough for D? If not, we need a different design. Each of these questions can be answer with a spike. If the spikes look good, then we have the design and it's time to expand on it.
I code in the direction of getting some real customer value as soon as possible, so a customer can tell me where I should be going.
Because I always get things wrong, I rely on refactoring to help me get them right. Refactoring is risky, so I have to write unit tests as I go. Writing unit tests after the fact is hard because of coupling, so I write my tests first. Staying disciplined about this stuff is hard, and a different brain sees things differently, so I like to have a buddy coding with me. My coding buddy has a nose, so I shower regularly.
Let's call it "Extreme Programming".
"White boards, sketches and Post-it notes are excellent design
tools. Complicated modeling tools have a tendency to be more
distracting than illuminating." From Practices of an Agile Developer
by Venkat Subramaniam and Andy Hunt.
I'm not convinced anything can be planned in advance before implementation. I've got 10 years experience, but that's only been at 4 companies (including 2 sites at one company, that were almost polar opposites), and almost all of my experience has been in terms of watching colossal cluster********s occur. I'm starting to think that stuff like refactoring is really the best way to do things, but at the same time I realize that my experience is limited, and I might just be reacting to what I've seen. What I'd really like to know is how to gain the best experience so I'm able to arrive at proper conclusions, but it seems like there's no shortcut and it just involves a lot of time seeing people doing things wrong :(. I'd really like to give a go at working at a company where people do things right (as evidenced by successful product deployments), to know whether I'm a just a contrarian bastard, or if I'm really as smart as I think I am.
I beg to differ: UML can be used for application architecture, but is more often used for technical architecture (frameworks, class or sequence diagrams, ...), because this is where those diagrams can most easily been kept in sync with the development.
Application Architecture occurs when you take some functional specifications (which describe the nature and flows of operations without making any assumptions about a future implementation), and you transform them into technical specifications.
Those specifications represent the applications you need for implementing some business and functional needs.
So if you need to process several large financial portfolios (functional specification), you may determine that you need to divide that large specification into:
a dispatcher to assign those heavy calculations to different servers
a launcher to make sure all calculation servers are up and running before starting to process those portfolios.
a GUI to be able to show what is going on.
a "common" component to develop the specific portfolio algorithms, independently of the rest of the application architecture, in order to facilitate unit testing, but also some functional and regression testing.
So basically, to think about application architecture is to decide what "group of files" you need to develop in a coherent way (you can not develop in the same group of files a launcher, a GUI, a dispatcher, ...: they would not be able to evolve at the same pace)
When an application architecture is well defined, each of its components is usually a good candidate for a configuration component, that is a group of file which can be versionned as a all into a VCS (Version Control System), meaning all its files will be labeled together every time you need to record a snapshot of that application (again, it would be hard to label all your system, each of its application can not be in a stable state at the same time)
I have been doing architecture for a while. I use BPML to first refine the business process and then use UML to capture various details! Third step generally is ERD! By the time you are done with BPML and UML your ERD will be fairly stable! No plan is perfect and no abstraction is going to be 100%. Plan on refactoring, goal is to minimize refactoring as much as possible!
I try to break my thinking down into two areas: a representation of the things I'm trying to manipulate, and what I intend to do with them.
When I'm trying to model the stuff I'm trying to manipulate, I come up with a series of discrete item definitions- an ecommerce site will have a SKU, a product, a customer, and so forth. I'll also have some non-material things that I'm working with- an order, or a category. Once I have all of the "nouns" in the system, I'll make a domain model that shows how these objects are related to each other- an order has a customer and multiple SKUs, many skus are grouped into a product, and so on.
These domain models can be represented as UML domain models, class diagrams, and SQL ERD's.
Once I have the nouns of the system figured out, I move on to the verbs- for instance, the operations that each of these items go through to commit an order. These usually map pretty well to use cases from my functional requirements- the easiest way to express these that I've found is UML sequence, activity, or collaboration diagrams or swimlane diagrams.
It's important to think of this as an iterative process; I'll do a little corner of the domain, and then work on the actions, and then go back. Ideally I'll have time to write code to try stuff out as I'm going along- you never want the design to get too far ahead of the application. This process is usually terrible if you think that you are building the complete and final architecture for everything; really, all you're trying to do is establish the basic foundations that the team will be sharing in common as they move through development. You're mostly creating a shared vocabulary for team members to use as they describe the system, not laying down the law for how it's gotta be done.
I find myself having trouble fully thinking a system out before coding it. It's just too easy to only bring a cursory glance to some components which you only later realize are much more complicated than you thought they were.
One solution is to just try really hard. Write UML everywhere. Go through every class. Think how it will interact with your other classes. This is difficult to do.
What I like doing is to make a general overview at first. I don't like UML, but I do like drawing diagrams which get the point across. Then I begin to implement it. Even while I'm just writing out the class structure with empty methods, I often see things that I missed earlier, so then I update my design. As I'm coding, I'll realize I need to do something differently, so I'll update my design. It's an iterative process. The concept of "design everything first, and then implement it all" is known as the waterfall model, and I think others have shown it's a bad way of doing software.
Try Archimate.

Do you use design patterns?

What's the penetration of design patterns in the real world? Do you use them in your day to day job - discussing how and where to apply them with your coworkers - or do they remain more of an academic concept?
Do they actually provide actual value to your job? Or are they just something that people talk about to sound smart?
Note: For the purpose of this question ignore 'simple' design patterns like Singleton. I'm talking about designing your code so you can take advantage of Model View Controller, etc.
Any large program that is well written will use design patterns, even if they aren't named or recognized as such. That's what design patterns are, designs that repeatedly and naturally occur. If you're interfacing with an ugly API, you'll likely find yourself implementing a Facade to clean it up. If you've got messaging between components that you need to decouple, you may find yourself using Observer. If you've got several interchangeable algorithms, you might end up using Strategy.
It's worth knowing the design patterns because you're more likely to recognize them and then converge on a clean solution more quickly. However, even if you don't know them at all, you'll end up creating them eventually (if you are a decent programmer).
And of course, if you are using a modern language, you'll probably be forced to use them for some things, because they're baked into the standard libraries.
In my opinion, the question: "Do you use design pattern?", alone is a little flawed because the answer is universally YES.
Let me explain, we, programmers and designers, all use design patterns... we just don't always realise it. I know this sounds cliché, but you don't go to patterns, patterns come to you. You design stuff, it might look like an existing pattern, you name it that way so everyone understand what you are talking about and the rationale behind your design decision is stronger, knowing it has been discussed ad nauseum before.
I personally use patterns as a communication tool. That's it. They are not design solutions, they are not best practices, they are not tools in a toolbox.
Don't get me wrong, if you are a beginner, books on patterns will show you how a solution is best solved "using" their patterns rather than another flawed design. You will probably learn from the exercise. However, you have to realise that this doesn't mean that every situation needs a corresponding pattern to solve it. Every situation has a quirk here and there that will require you to think about alternatives and take a difficult decision with no perfect answer. That's design.
Anti-pattern however are on a totally different class. You actually want to actively avoid anti-patterns. That's why the name anti-pattern is so controversial.
To get back to your original question:
"Do I use design patterns?", Yes!
"Do I actively lean toward design patterns?", No.
Yes. Design patterns can be wonderful when used appropriately. As you mentioned, I am now using Model-View-Controller (MVC) for all of my web projects. It is a very common pattern in the web space which makes server-side code much cleaner and well-organized.
Beyond that, here are some other patterns that may be useful:
MVVM (Model-View-ViewModel): a similar pattern to MVC; used for WPF and Silverlight applications.
Composition: Great for when you need to use a hierarchy of objects.
Singleton: More elegant than using globals for storing items that truly need a single instance. As you mentioned, a simple pattern but it does have its uses.
It is worth noting a design pattern can also highlight a lack of language features and/or deficiencies in a language. For example, iterators are now built in as part of newer languages.
In general design patterns are quite useful but you should not use them everywhere; just where they are a good fit for your needs.
I try to, yes. They do indeed help maintainability and readability of your code. However, there are people who do abuse them, usually (from what I've seen) by forcing a system into a pattern that doesn't exist.
I try to use patterns if they are applicable. I think it's kind of sad seeing developers implement design patterns in code just for the sake of it. For the right task though, design patterns can be very useful and powerful.
There are many design patterns beyond the simple that are used in "real world". Good example Stackoverflow uses the Model View Controller Pattern. I have used Class Factories multiple times in projects for my employer, and I have seen many already written projects using them as well.
I am not saying every design pattern is being used but many are.
Yes we do, it usually happens when we start designing something and then someone notices that it resembles an existing pattern. We then take a look at it and see how it would help us achieve our goal.
We also use patterns that are not documented but that emerge from designing a lot.
Mind you, we don't use them a lot.
Yes, Factory, Chain of Responsibility, Command, Proxy, Visitor, and Observer, among others, are in use in a codebase I work with daily. As far as MVC goes, this site seems to use it quite well, and the devs couldn't say enough good things in the latest podcast.
Yes, I use a lot of well known design patterns, but I also end up building some software that I later find out uses a 'named' design pattern. Most elegant, reusable designs could be called a 'pattern'. It's a lot like dance moves. We all know the waltz, and the 2-step, but not everyone has a name for the 'bump and scoot' although most of us do it.
MVC is very well known so yes we use design patterns quite a lot. Now if your asking about the Gang of Four patterns, there are several that I use because other maintainers will know the design and what we are working towards in the code. There are several though that remain fairly obscure for what we do, so if I use one I don't get the full benefits of using a pattern.
Are they important, yes because it gives you a method of talking about software design in a quick efficient and generally accepted way. Can you do better custom solutions, well yes (sorta)?
The original GoF patterns were pulled from production code, so they catalogued what was already being used in the wild. They aren't purely or even mostly an academic thing.
I find the MVC pattern really useful to isolate your model logic, which can than be reused or worked on without too much trouble. It also helps de-coupling your classes and makes unit testing easier. I wrote about it recently (yes, shameless plug here...)
Also, I've recently used a factory pattern from a base class to generate and return the proper DataContext class that I needed on the fly, using LINQ.
Bridges are used when trying when trying to glue together two different technologies (like Cocoa and Ruby on the Mac, for example)
I find, however, that whenever I implement a pattern, it's because I knew about it before hand. Some extra thought generally goes into it as I find I must modify the original pattern slightly to accommodate my needs.
You just need to be careful not to become and architecture astronaut!
Yes, design patterns are largely used in the real world - and daily by many of the people I work with.
In my opinion the biggest value provided by design patterns is that they provide a universal, high level language for you to convey software design to other programmers.
For instance instead of describing your new class as a "utility that creates one of several other classes based on some combination of input criteria", you can simply say it's an "abstract factory" and everyone instantly understands what you're talking about.
Yes, design patterns or abstractly patterns are part of my life, where I look, I begin to see them. Therefore, I am surrounded by them. But, as you know, little knowledge is a dangerous thing. Therefore, I strongly recommend you to read GoF book.
One of the main problems about design patterns, most developers just do not get the idea, or do not believe in them. And most of the time they argue about the variables, loops, or switches. But, I strongly believe that if you do not speak the pattern language, your software will not go far and you will find yourselves in a maintenance nightmare.
As you know, anti-pattern is also dangerous thing and it happens when you have little expertise on design patterns. And refactoring anti-patterns is much more harder. As a recommended book about this problem please read "AntiPatterns: Refactoring Software, Architectures, and Projects in Crisis".
Yes.
We are even using them in my current job: Mainframe coding with COBOL and PL/I.
So far I have seen Adaptor, Visitor, Facade, Module, Observer and something very close to Composite and Iterator. Due to the nature of the languages it's mostly strutural patterns that are used. Also, I'm not always sure that the people who use them do so conciously :D
I absolutely use design patterns. At this point I take MVC for granted as a design pattern. My primary reason for using them is that I am humble enough to know that I am likely not the first person to encounter a particular problem. I rarely start a piece of code knowing which pattern I am going to use; I constantly watch the code to see if it naturally develops into an existing pattern.
I am also very fond of Martin Fowler's Patterns of Enterprise Application Architecture. When a problem or task presents itself, I flip to related section (it's mostly a reference book) and read a few overviews of the patterns. Once I have a better idea of the general problem and the existing solutions, I begin to see the long term path my code will likely take via the experience of others. I end up making much better decisions.
Design patterns definitely play a big role in all of my "for the future" ideas.