So I've spent the last few days looking for a way to create a simple image drawing app with wxPython, and I think the key to doing just that is understanding how to use Device Contexts. The problem is that the wxPython demo program doesn't demonstrate DCs, and the docs for both wxPython and wxWidgets don't explain as much as I'd like to know so I've decided to try and 'reverse engineer' an existing app to see how its done.
The first problem I have is that I don't know of any drawing apps written in wxPython (or any written in Python for that matter o.o), and the second is I don't know how I'd go about doing it. Am I right in saying that I'm going to need a copy of an application's Python source and something like Winpdb? What do professional programmers do when they find themselves in a situation like mine, needing answers that the docs don't provide?
If you need to understand the concepts, but the docs don't cut it, it's worth it to look at docs for similar APIs. In the case of drawing contexts, there are a lot of similar APIs in other languages. Java has Swing for instance.
Reverse engineering is easier in tools that aren't big event-driven GUI things. The converse is that event-driven GUI things tend to copy each other, so you only need to figure them out once or twice before they all make sense.
In .NET world, I have Reflector as indispensable tool.
In my company, we use to program SharePoint websites. There are many "gotchas" we just figure out by reverse engineering that product assemblies, exactly because documentation is plain wrong, just missing or simply doesn't exists.
Related
Hi I am a Student in Norway looking for a good general tutorial on Action Script and how to use it,and what it's for.
I have been looking around google for a while and I can't seem to find any good or "simple" way to learn or even understand how it works.
sites i've been too:
(http://www.actionscript.org/resources/categories/Tutorials/)
(http://www.flashandmath.com/)
(http://tutorials.flashmymind.com/)
(http://tutorialoutpost.com/tutorials/flash/actionscript)
(http://www.tutorialguide.net/programming/actionscript/)
(http://www.siteground.com/tutorials/actionscript/)
(http://www.kirupa.com/developer/flash/index.htm)
(http://www.freeprogrammingresources.com/actionscript.html)
(http://www.adobe.com/devnet/actionscript.html)
So what do I want to know ?
Basic scripting to advanced scripting.
Where it's best to use action script. (best functions)
A simple yet efficient explenation that alot of people might understand.(if possible)
So if there is any way you guys might be able to help me with this little problem of mine I would be forever in your debt.
and thanks in advance for any info that might come my way, even if it helps me or not.
Check out this too: http://www.gotoandlearn.com/. It has some good free tutorials, but if I remember correctly, you need to pay for the full series!..
And the best approach to learn something is to read the documentation while working on something! Try create a game/small site/interactive animation/etc and when you are stuck, search the answer or ask for help!
ActionScript is similar to Java and C++ but different. It runs on the Flash Player. It is generally used for applications ranging from online games to video players to Rich Internet Applications.
Flash can be developed from 2 perspectives:
Designer's perspective: This approach consists of drawing objects, shapes etc on a stage like you do in an image editing software, and then animating / adding actions to the drawn objects. You develop this in Flash Professional (Link here)
Developer's perspective: This approach consists of developing using the Flex framework, from an IDE (Flash Builder)
Check these out. I learnt it by looking at various tutorials on the net (do a Google search, you'll find plenty), so you can learn from the net as you go.
I often recommend Colin Moock's Lost Actionscript Week End video tutorials , it's an excellent resource if you want to grasp the general concept behind AS3 and leaves you with enough understanding so that you're able to tackle books on Object Oriented programming, AS3 language reference, basically tools that you will eventually need when you get deeper into the subject.
http://tv.adobe.com/show/colin-moocks-lost-actionscript-weekend
Why don´t you try the official Google Action Script documentation? You can find it at https://developers.google.com/apps-script/ . I fount it very useful and easy to understand... It is very well organized and there are many examples with diverse grade of complexity. For example: you have there 5-minutes overview for your first Google Action Scrpipt https://developers.google.com/apps-script/overview#what_can_apps_script_do
And if you are looking for a more complex example, you can go forward to end-to-end examples: https://developers.google.com/apps-script/articles/bracket_maker
That is my first reference point with Google Action Script...
I have been struggling with an idea for a few weeks and wanted to see if someone can help me out here.
Programming today is full of abstractions, and people who do not understand the abstractions, do not truly understand the reason or design than went into building that abstraction/layer/framework and will struggle as soon as they step outside the comfort zone.
I was wondering if there is a learning resource that goes about teaching programming in an incremental fashion. This will lead to understanding the full stack.
take a small problem
implement a simple solution
talk about the the solution and the designs used
convert the solution into a framework or utility of some sort
now extend the problem space and repeat from step 2.
This way when someone then picks up any framework/library, they can easily visualize the problems the framework is trying to solve, the design decisions taken and the reasons thereof.
[Added to clarify the intent]
Based on the answers and comments below, I want to clarify that I want to move further up the stack. Building your own ORM to understand ORM better, same goes for ActiveRecord, IOC container, data binding, templating engine, and the host of other magic/glue/plumbing we use day-to-day.
Thanks.
Here's what I recommend : Have a brush with assembly (just one book or one month is enough). Have a good strong review of C++ (hopefully it will teach you some of C as well). Now the world is yours. Python is made in C/C++ , Object C is pretty close to c++, .NET is in C++ and C#/VB.NET , The windows API is oriented for C.
I picked C# as my abstract language of choice after this by the way.
Read the source. It is a good idea to build something you want to understand, but you can enhance your understanding of concepts significantly by looking at how something is built. This is especially true for infrastructure pieces (ORM/DI/Templating) which you seem to be interested in.
Get the software to build on your machine, attach a debugger and trace through the code. This is pretty easy for C#/Java with a good IDE. For dynamic languages like Python and Ruby, it takes a good editor and a lot of grepping.
If it is a good software package, it will usually have tests. Tests are a great place to start digging into code. They usually make clear the intent of the code, and also provide you a logical starting point to peel off the layers and actually peek under the hood.
Build a fully functional compiler from scratch in a systems language like C or C++. Maybe it isn't the full stack, but it's a large part of it. This is something I want to do as well. If only I could find the time and space.
The best example of the sort of learning resources I am seeking is the MIX session by Rob Eisenberg on "BUILD YOUR OWN MVVM FRAMEWORK". It goes step by step on explaining the pattern and also implementing it at the same time, attacking one problem area at a time.
http://live.visitmix.com/MIX10/Sessions/EX15
Hope there are more out there.
I learnt swing basics and event handling basics from head first java...
Then i read a few tutorials on swing app development using netbeans...
and i loved it as i don't have to care about layouts and stuff...
But i read in one of the forums, that i should learn swings properly rather than using netbeans directly...
This confused me a bit....
Please suggest the best way to master development of swing apps....
thanks in advance
Well, I see I'm going to run counter to the majority here ;-)
Hand coding GUIs is a pain in the ass. Anything that makes that task easier is a good thing in my book. When you're just starting, having a generated GUI lets you get up and running faster.
GUI builders handle the really repetitive work and prevent you from doing the most common dumb things. The downside is that same approach will also prevent you from doing the really clever things. Eventually, you will encounter something that you cannot do through the GUI builder and you will need to poke into the code. So, you can't treat code generators like black boxes where you don't need to know what magic happens inside. At minimum, you need white boxes. Let the GUI builder do its magic, but understand that magic and its limitations.
Practice by generating a very simple GUI. Walk through the code and understand what it does. Make a change through the builder and see how the generated code changes. Try changing the code yourself to confirm you understanding is correct. *
If you don't understand something, hit the JavaDocs, the Swing Trail, or browse through the Java2S Swing Tutorials.
If you're still stuck try the kind folks at Java Ranch, or here on StackOverflow.
* Netbeans puts the generated code in guarded blocks and will not let you edit them directly. However, you can open the file in another editor to test a change. Also, you can do quite a lot to influence the code generation using the code tab in the properties window.
It depends on what you see as your goal.
There is no "perfect" approach to get comfortable using Java and swing, it always depends on what you want the outcome to be like.
Most enterprises depend on stability and speed, programmers need to write code fast and stable. If you write complex interfaces by hand it gets ugly when it comes to speed and precision at the same time. You can never write better code in terms of "it is working" then the netbeans gui builder can. Also, no one will probably have a look at your code once the application is up and running.
If you want to get to know swing only for the purpose of knowing it with no deeper intention what so ever, I'd recommend learning it by heart without netbeans as you'll probably familiarize yourself with most of it's functionality quicker then the other way around.
On one hand, if I want to learn something, I want to learn it from scratch, so I would probably go with writing swing-code myself and in the end using netbeans to generate it when I am fully able to comprehend what is generated.
On the other hand, if I need to write applications quick and am not paid to go into any details, I'd simply use netbeans.
I think you have answered yourself... you want to master development of swing apps...
everything that you do by autogenerating without knowing why or how is not mastering in my opinion ;)
If you want to be master, then you should at least know how to do it with your bare hands. Moreover, it will also help you if you will use other gui toolkits (main principles of gui toolkits are more or less the same, imho).
I think I'm in somewhat of a unique situation: I have a decent amount of coding experience in C/C++ in a Linux environment. However, I don't really have "project experience." For example, I'm familiar with the concept of version control, but I've never used any. Or, i've never worked on a project with more than a half dozen source files.
So, where I am now is that I'm working on this project with a large amount of code already existing. I have to write all my code in a windows environment using Visual Studio 2008 (Visual C++ to be specific) So I have a few questions:
How do integrate the already existing code into VC++? I'm using tortoise SVN and I have all the code on my machine...
Does anyone have any general advice on moving from small projects to larger projects?
Any help/advice would be greatly appreciated
Some of the keys to coming to grips with a large codebase:
Learn the ins and outs of source control. For now, start with just learning how all the SVN commands work. SVNBook is a good resource for this. Use VisualSVN or a similar plugin to interact with your repository within your IDE (Tortoise is still useful when you want to interact from elsewhere). Down the road, you'll want to become intimately familiar with branching and merging (and the tools for doing so quickly and correctly), and perhaps learn a DVCS (distributed version control system) like Git or Mercurial. This will at the very least expand your mind a bit, and likely teach you some lessons that will be useful even in projects where you use more traditional (centralized) version control.
Learn how to quickly look for things, find the declarations of unfamiliar classes and variables, and trace the execution of the larger application. There are lots of approaches for this, and you'll likely use most of them at one point or another, but some of them are your IDE's built-in features (most of them are quite robust in this regard, you should be able to right-click on a class name and find its declaration easily), grep and the like (ack is a variant that is very suitable for code spelunking), and CTAGS if you swing that (C/C++) way.
Learn the basics of unit testing, maybe even try out a framework like NUnit. Personally I'm not big into unit tests, but I recognize their utility and many swear by them, so don't knock it 'til you've tried it, at least.
Even if you're a flawless programmer with a robust battery of unit tests, large codebases demand a higher level of debugging skill, due to the inherent complexity of the problems that crop up. Whether it's learning how to write concise, descriptive debug printf()-like statements, becoming more familiar with your debugger, or even learning the ins and outs of your language (e.g. the corner cases of the type system/object model) can be helpful in unwinding these complex issues.
Unfortunately, I haven't used Visual Studio, but I think getting to know your IDE's project import/migration flow will be instructive too. Maybe somebody else will chime in with more concrete advice on that front. The process can be onerous, especially if you had a non-standard custom build system before and you want everything to be done The One True Visual Studio Way henceforth, but the tools for automatic dependence extraction from code are getting better and better.
The ideas already given are very good. But you also might want to read Mike Gunderloy's Coder to Developer. From your description of your current experience, I think you'll find it useful. Also read The Pragmatic Programmer; I keep it in my office by my desk, and often find myself loaning it to younger developers.
Just dive in. Hopefully whoever has been working on this project so far organized the code into logical groups (namespaces, class hierarchies, folders).
I'll also second Matt J on learning how to use the IDE: I'm not familiar with Visual Studio specifically, but there should be contextual menu items when you click on a class or method to take you to the place where it was declared, and from there to the classes it was derived from.
Get version control set up first though: you'll feel more comfortable poking around once you learn how to "revert" ;)
I have been using VisualSVN for quite a while without problems. It integrates perfectly with vs2008. As for moving on to large projects, a great way to see how things are done is to download the source of a decent size existing project and see how it was put together. After you've got a good idea of how things are structured, the best thing you can do for yourself is to write code. Brainstorm a project and go at it. Depending on how you feel about your outcome after completion, you could use it as part of your portfolio as well.
Unit tests. Use them or you'll regret it.
Get to know Visual Studio well, if you live in it, you really have to know it well.
AnkSVN is a free plug-in for Visual Studio 2008, and it works very well.
Also, Refactor for C++ is another free plug-in and one of the only ways to get refactoring support in Visual C++.
Also, you will soon learn that on large projects, 80% of your time is going to be spent doing code maintenance, so do yourself a favour and make your code a place in which you want to live, not a place of terror that you shrink back from. Clean code, the occasional comment, and unit tests will go a long way to making you want to get up and go to work in the morning, rather than dreading that you have to work on that monstrosity where anytime you touch anything it breaks.
I am designing software that needs to draw several different kinds of charts--bar charts, pie charts, flow charts/graphs, charts over time. I am looking for resources related to both the programming side of the issue as well as the UI/display side. Books, online resources would all be helpful. Thanks.
It does depend on the language a bit: here may be some pointers for you. Hope they help:
code.google.com/apis/chart/
home.gna.org/pychart
Practical C# Charts and Graphics
The Excel library can be imported by the Office API, but it does require you to have Excel installed.
Gnuplot
The grammar of graphics: book from the guy that wrote the plotting lib of spss. Somewhat theoretical, but nice xml treatment... gives you the graph xml schema for spss.
But I'm sure there are quite a few others that other people will know.
Do you have to draw it your self. If you want to save time (and probably money) then you can try embedding one of these into your apps http://code.google.com/apis/chart/
Ditto with Chris; If you are developing a new way of building charts, that's great!
Assumption: I have no idea of your needs but it would initially strike me (and thus form my assumption) that you are trying to develop a better charting software and that's usually interface.
Consider checking out the libraries in other programming languages that already do charting.
Adobe Flex/Air have one, PHP does, Java Does, .NET does.. etc.
Checking out the existing charing libraries for your language of choice helps a lot. In my case, it helped so much I decided not to write my own. ;)
For .net apps we settled on .netCharting, which can be pretty amazing.
The real lesson I took from it though, is this: there are way, way more kinds of charts than I thought there were, and I work with a lot of charts. Make sure you end up with something modular enough to handle clicking in new chart types / configurations with minimal effort.
You want to take a look at EyeSee.
http://moose.unibe.ch/tools/eyesee