understanding an API - iphone

I know that there are many API's like json,Facebook,twitter etc for developing related applications on iphone....but how to understand an API?This might be scilly question but I want to know how? what would you suggest for for a beginner?

You should find relevant documentation and read through some code examples utilizing the API.
If you are looking for information about the iphone, as the tag suggests, then read through the information here. There is an entire section dedicated to sample code. If you really can't understand how to make something work after some effort and some googling, then you can always ask on StackOverflow.

When ever I came through adding new API in my project I usually scan though documentation to find relevant topic to my project then after looking at the some sample code I usually start experimenting with the code to get the desired results and thats it because API is for short term use, you should not waste your precious time on just one API. So steps are, 1) find the relevant topic then 2) read sample code and 3) write your own code to get the desired results. 4) through away that API.
Cheers
Ayaz Alavi

If it's open source, read the code from beginning to end. Or to see why things were designed in a certain way, maybe try reimplementing parts of the API.

Related

What Should I Read To Become Familiar with Developing using SocialEngine?

I am capable with PHP, HTML, CSS, JavaScript and SQL, and not bad with Drupal. Very recently, I acquired a customer that wants me to do some SocialEngine 4.xxx customization. My customer is aware that I have no experience with SocialEngine, but am capable with the underlying technologies (I gave him a lower hourly rate because of this too.)
I'm not seeing very much online that is geared towards someone like me. Where can I read about modifying SocialEngine that assumes very little knowledge about SocialEngine, but a competency at programming?
For example, I spent a few hours today trying to figure out how to conditionally display a block based on a Membership Level. It appears there is no way to do this using the GUI. No problem, I found some code that seemed like I could get it to work that would grab the user's membership level. However, where do I put this? Honestly, I'd like to have this at the block-level. SocialEngine doesn't seem to allow me to place arbitrary PHP code into a block, and even if it did, would that be the "SocialEngine" way of doing this? Should all custom logic like this be a module in SocialEngine, that attaches to events using hooks?
Thank you very much for looking at my question,
-Brian J. Stinar-
I've written a blog about accessing data through models, creating widgets and modules. You can find out about the general structure of Social Engine at http://garbtech.co.uk / http://socialenginetutorials.co.uk (both same blog)
Unfortunately, there are no books or official documentation on SocialEngine PHP API. Your only choice is to check out various (incomplete) guides over the Internet or study their source code and figure things out by yourself.

Getting started with Lift

I want to learn Lift. Unfortunately, all documentation which I tried either obsolete, unreadable, incorrect or combination of the above. I tried the following:
Simlply Lift. Some things from the book I tried lead to errors.
Exploring Lift. The structure of book is very bad. It's hard to read and try out code in the wild at the same time.
Lift in Action. The same as the previous but you need to pay for it.
P.S. I've seen similar questions. Most of them were asked a long time ago. Did the situation improve from the time of that writings?
P.P.S. Are there any other type safe scala web frameworks (Don't offer Play 2.0. It's not typesafe. I don't see any reason to create it in Scala).
It is unfortunately true that the state of Lift documentation is uneven at best and there are huge gaping holes.
However, the Lift community is just full of awesomely helpful people.
My recommendation is not to play around, but rather to try and implement something. If you get stuck, ask specific, direct questions about what you're trying to do, how you're doing it and why it isn't working.
So far, though I would wish for better documentation, I've been able to get every answer that I needed either through Google or on the Lift mailing list - though I expect I might ask more questions here in the future.
The Lift documentation is not its strong point. The philosophy is more "try and ask if you have any problem". Here are a few tips:
Assembla
One ressource that is really useful is http://www.assembla.com/wiki/show/liftweb, there are a lots of examples so you can progressively learn how it works.
Mailing List
Otherwise you can always use the mailing list if you have specific questions even if in my opinion it is really hard to explore it fast in order to solve a problem which was already encountered. http://groups.google.com/group/liftweb
Stack Overflow
Finally, a small community is present on Stackoverflow so feel free to ask in here. This is a good way of looking for answers and creating documentation in the same time.
Source code
Don't hesitate to explore the source code and the scaladoc if you have specific questions/doubts about the behavior of a function, they are often short and even sometimes commented! http://scala-tools.org/mvnsites/liftweb-2.4-M4/#package
Have a look at the Lift Cookbook: http://cookbook.liftweb.net/
"Simlply Lift. Some things from the book I tried lead to errors."
What exact type of errors did you have? Have you tried to follow it with "Simply Lift" examples that you can download from GitHub
https://github.com/dpp/simply_lift?
Only errors I had were related to my lack of experience with SBT, but that's another story.
I have started with Lift mostly from that source (Simply Lift + examples) and in combination with its great community and Google (ChrisJamesC has listed the main links really nice) it was quite okay for me.
I would suggest you to work out all examples given in the "Simply Lift" tutorial or at least work them out unless you feel comfortable enough to jump right "in media res" and try something by yourself. That was the best way of learning Lift for me.
Also, whenever you got stuck somewhere and can't find solution on the web, your questions would be welcome and answered on the Lift Google Group (https://groups.google.com/forum/?fromgroups=#!forum/liftweb). David Pollak is very often right there to answer your questions directly so I have only words of praise for this framework's community and Lift's
creator.
P.S. Lift's documentation could be better organized, some stuff could be better explained for sure, but IMHO it was just too small a price I had to pay to enjoy such beautiful framework. Learning curve is steeper than with Play, especially in the beginning, but after I "survived" the very first week it was almost impossible for me to give up of all of its advantages and original concepts (Lift's "Seven Things") and switch to another framework.

Wikipedia as part of my iOS app

I would like to download information from wikipedia to my iOS app. Firstly, I created simple RSS reader, but I can't download date from wiki. Now, I think that I should create parser for wiki.
What do you think about this? Any ideas?
Thanks,
Tomek
In my opinion, parsing a website is never a good idea. Only the smallest change in the design of the website can break your application and make it unusable. I'd try to get to your data in an alternative way. ;-)
Sandro Meier
Scrapping a web site directly from your app is never a good idea. If you are ever going to do that it is suggested that you do it on a server and provide the data to your app in a well known format, so that site changes can be quickly managed by your server, and as a result, never breaking your app.
Although wikipedia does not have a formal API, it provides some other ways of extracting data from its servers. You should check this link:
http://en.wikipedia.org/wiki/Wikipedia:Creating_a_bot#APIs%5Ffor%5Fbots
I know this question is quite old. But I've dealt with the same problem and wrote this very small library. I am using the mediawiki api (Mentioned in the post from Felipe) to get the needed information.
https://github.com/prine/WikiApiObjectiveC

Understanding a software system

I recently became part of a complex embedded project team for which I will be developing a part. For the part which is my responsibility there is only old code and not much documentation.
I am keen to make a good start but shyness and fear of appearing stupid makes it difficult to ask questions. How to ask questions ?
I wanted to ask what techniques do you guys use to understand a project ? I mean there are of lots of technical details which one must remember and keep in context in order to make a design. Your read the code and get some facts but how to move ahead ?
For instance you read the code and the document(s) and get some facts A and fact B . How to reach suitable conclusion X for which you may or may not have needed to take into account facts C and D also ?
Code-reading can be particularly difficult if there is not enough documentation and the code is poorly documented and badly written. I guess the best way now is to find the entry point of the code, and slowly understand its flows and what data it uses. I would keep a look out for
Structure - are there any partitioning of entities/system? Where in the code (and how) do they communicate with each other?
Data - what sort of structures are used to hold the global data? How are the data accessed and saved?
If you are doing C or C++, it is also important to find out how memory is handled and for C++ (and other related non-managed memory OOP languages, I guess), how are object ownership contained.
Since it is an embedded project, are there any non-standard code or coding constructs used?
Reading the code is balanced by writing the documentation.
Write the documentation that your replacement will need. Imagine someone who knows less than you. Explain it for that person.
When you cannot explain something to your replacement, ask questions.
When you have a complete description, you will "know" the system.
And you will have produced complete documentation.
You don't mention what kind of tests exist. If there are test cases, modify them and trace how this would affect the end result.
You might want to look at diagrams which give the entire picture of the logical structure of the system, like, for example, looking at class diagrams in an OOP system would be of great help. Looking at the design diagrams of large and complex apps gives you a clear understanding of how the internal modules of the system are organized and this way its makes the task of figuring out what functionality does a particular piece of code does much much easier. In the absence of diagrams, you're best bet would be to start from the entry point of the app, like main() and proceed from there while you draw(literally draw or write down on paper) your own conclusions about the system(this way you can have your own documentation) and ask your peers if they're correct.
My experience is that it's best to start with some kind of task -- a bug fix or other small change. That will provide focus to your learning. I find it hard to read through a binder or sift through pages of source code or documentation without having a way to apply it.
If you have a sandbox where you can play with changes that you've made without messing up the code base, that can be even more helpful.

Do Poor Code Samples Turn You Away From Libraries?

I've been evaluating a framework that on paper looks great. The problem is that the sample code is incomplete and of poor quality. The supplied reference implementations are for the most part not meant to be used (so they can be considered as sample code as well) and have only succeeded at confusing me.
I know that it's common for things to look better on paper, but my experience with the sample code is turning me away from further investigation.
Do you let poor code samples change your judgment of frameworks/libraries? So far my experience has been similar to the "resume effect": if someone doesn't put the effort into spell checking their resume, they probably won't get the job...
For me, it does. I tend to want to avoid libraries where the code samples are incomplete. If the library is open source, I will overlook it, since I can directly look at the code and see if the library's internals are reasonable, and I know that, if there is a problem someday, I could (if I had to) fix it.
If the library is commercial, and their samples and/or documentation is poor, I look elsewhere. I just see it as risk management - poor samples make me fear the quality of the library in general.
No matter how good something is on paper or in theory, it can still be crap when programmed.
I think this is a valid reason to turn away from and evaluate other libraries. As a potential user of a library a lack of documentation and/or bad code samples gives the impression that the library is not yet mature enough for use by third parties. In time it may well gain the missing pieces but until then I think its reasonable to look elsewhere.
I was recently evaluating the multitude of blogging applications that people have uploaded to github.com I quickly skipped ones that no documentation as they obviously weren't ready for others to use. The ones that remained at the end had a good README with info on how to get the app up and running as well as an online example of the code running.
Poor code samples combined with poor documentation will make me turn away from a library unless there is a compelling reason to use it. However, a library that has either good code samples or good documentation is usually worth using. (Assuming that the library itself otherwise meets my needs.)
If I can't find good examples (and/or documentation) illustrating how to use the library, I'm definitely less likely to use it - just as a practical matter, it'll be harder for me to figure out how. But I don't care what the code that implements the library itself looks like. I don't think I'd choose one library/framework over another just because the developers of the one have shown an ability to write cleaner code (which is what I understand the "resume effect" to mean).
Lack of documentation and examples makes me a whole lot less likely to use that particular library. It's not worth my time testing and trying to figure out how a black box works if there are alternate solutions to the problem out there.
Yes, definitely. Every library should come with a simple example using program and a CLI interface (for very simple libraries with <3 methods and <10 hooks, one example should suffice).
And why does your framework "look great" if it's so hard to use that even the original coders make mistakes using it?
It certainly matters to me. Evidence of sloppy/incomplete coding and poor communication decreases my confidence that the actual implementation code is stable and robust.
Myself yes, but there must be people out there who aren't turned off by this otherwise there are plenty of open source projects that would have died a long long time ago.