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Hi guys I'm newbie to android development and I need some help...
I want to make an app that will use data from an xml database and there are two points where I need help cause I find java with xml too complicate...
eg.
Code:
<items>
<1><name>box</name><price>2.00</price></1>
<2><name>pencil</name><price>1.00</price></1>
</items>
1)get a single xml value from a child node(eg.name of 1st item - "box")
2)get an xml database from child nodes (to use it as data source for a listbox) - this one is not nessesary
Thank you for your time guys...
I had never used xml in my programs before android either, so when starting off I found xml a little uncomfortable and found myself wanting to avoid it too. If you take the time to learn how the different xml files are used and how these objects can (easily) be used in your code, I think you'll see why its a lot better to just go with it. It helped things click for me when I understand that every xml object/attribute has a related java object/setmethod, which made me realize how much more organized and simple my code was using the xml.
I don't fully understand what your asking how to do, but it sounds like your trying to "swim upstream" by developing your own system of xml instead of using the android xml namespace. I would recommend doing some reading at developer.android.com, its really not too hard to get your head around and I think it will make your development go a lot more smoothly
Hi guys its me again. I send a lot of hours on searching about an easy way to use xml...
The easier way I have found called DOM but I have 2 questions:
1) how to load files from an android project easily(refered with less command line and without using inputstream)
2) how to use xpath to easily navigate on android
Prefered to see some examples...
Thanks 4 all...
I want to make an application for my phone, I have all the necessary programs to create an app. But I do not know the "language" used in the programs like eclipse. I'm assuming I have to learn the code but don't know where to start. Anybody have good sources for learning it?
There are a number of free lessons and tutorials on Java floating around out there. You may also want to check out http://forum.xda-developers.com/showthread.php?t=667298. It has a lot of information that may be helpful in it.
Same here. Thx for the info!
Hey everyone; it wouldn't let me post in the development subforum due to the fact that I just joined, but I figured my topic would be just as relevant here.
I'm a sophomore CompSci major. Java is my strong point, but I'm far from a master. I know syntax, I know how to follow what's going on in more advanced programs, but writing them is the tough part. Anyway, I would like to create my first app; something simple. I was thinking a calculator with a small clipboard on the side (hold the button to store the number displayed in the window, hit it to place that value). It would be insanely helpful for my physics class.
So a few questions for you guys:
-Is there anything I should know beforehand? Anything to be careful of?
-Can I use Eclipse? I tried with App Inventor, and it's too limited.
-How do I obtain examples of more complex apps? Can I unpackage the apk files into java classes?
-Is there a site similar to the sun library, where it lists the available classes/objects/imports?
I'm sorry if I don't know the lingo just yet (of Droid or Java). Picking this all up is a little difficult for me, but I'm trying
Thank you in advance for even taking the time to read this. I understand rookies must aggravate you guys, but from what I've seen, the community has been nothing but welcoming!
You can definitely use Android SDK with Eclipse.
This guide will help you with install and set up process
http://developer.android.com/sdk/installing.html
SDK also contains sample projects that you can use for learning.
I don't remember about unpackaging apk files, but I'm pretty sure they contain already compiled .class files, which will be of no use to you.
And here's Android's reference page:
http://developer.android.com/reference/packages.html
Also the dev guide is very useful for learning the basics:
http://developer.android.com/guide/index.html
Resources section has useful tutorials as well!
Hope that helps. Good luck with your app!
Thank you, meshdub! And all branching from the same site; sure made me look bad...but on the upside, you've introduced me to a source I will be able to use throughout my software development lifetime.
If there's any more you or anyone else could give me as far as what to expect or look out for, please let me know! I'm honestly a little intimidated by this; I'm not too familiar with forums, and I've heard how difficult app developing can be.
But this should keep me occupied for a while, and again, thank you very much
I am looking for analysis tools specific for Android app development!
I have found many tools online that are not specific for Android, only for Java, either free or commercial, like the famous FindBugs but it is not interprocedural so for example it loses several bad NullPointerExceptions that may occur at runtime! Other tools (like CheckStyle) perform just a syntax check that sometimes is not so powerful, and other tools are not suitable for Android app development
What are, among the available tools, those that you prefer and really use?
What kind of properties do these tools check?
What kind of bugs do these tools detect and remove (among the most common errors that an Android developer may do)?
Please help me with sharing your experiences and suggestions, thanks!
Nobody uses any tool for detecting bugs?
What kind of bugs are you specifically looking for? Solving NullPointers is hard to do automatically, it'll probably just show you where the error is and what it is.
And the emulator/logcat does that, too...
bassie1995 said:
What kind of bugs are you specifically looking for? Solving NullPointers is hard to do automatically, it'll probably just show you where the error is and what it is.
And the emulator/logcat does that, too...
Click to expand...
Click to collapse
I would like to detect the most common errors that may happen during Android app development, like NullPointerExceptions, ClassCastExceptions, OutOfMemory Errors, and so on... but with tools like FindBugs that don't need to execute the app first.
subtask said:
I would like to detect the most common errors that may happen during Android app development, like NullPointerExceptions, ClassCastExceptions, OutOfMemory Errors, and so on... but with tools like FindBugs that don't need to execute the app first.
Click to expand...
Click to collapse
I don't think that's really possible, it would have to be able to reason about and come up with the behaviour of your code like a human... Computers need to run it. The easiest thing you'll get right now is an explanation of what went wrong where, I think...
bassie1995 said:
I don't think that's really possible, it would have to be able to reason about and come up with the behaviour of your code like a human... Computers need to run it. The easiest thing you'll get right now is an explanation of what went wrong where, I think...
Click to expand...
Click to collapse
If you run FindBugs in your source code, it is able to detect many things, like potential NullPointerExceptions, before running your app...but unfortunately it is not powerful enough to detect interprocedural NullPointerExceptions...that's the reason I am looking for something different...
subtask said:
If you run FindBugs in your source code, it is able to detect many things, like potential NullPointerExceptions, before running your app...but unfortunately it is not powerful enough to detect interprocedural NullPointerExceptions...that's the reason I am looking for something different...
Click to expand...
Click to collapse
Yep, that's what I meant. Anyhow, I don't know about anything like it .
The Android SDK provides some API for automatic testing.
You will need to create a test project which checks the functions you want to achieve.
This can be used to ensure that your app is still working correctly after adding new features.
Hi
"static analysis tools" is probably the term you want to be using when looking for these sort of tools, the wikipedia page give a good selection to be going on with http://en.wikipedia.org/wiki/List_of_tools_for_static_code_analysis
Although I would add that if you're getting a lot of these sort of errors then you probably need to work on your own code writing skills and take the time to understand how and when these sort of issues occur rather than just relying on a plethora of tools which keep you dumb to what's going on! You'll benefit from it in the long run
One thing you might give a try is JetBrains Android Studio. It seems to have a decent static analysis tool which is the same used for ReSharper with Visual Studio.
Try Lint, it comes with ADT,
with Eclipse you can right click your project, ans under android tools you will see something like check lint errors
It will create lots of errors, which are just recomendations, you can simply delete those errors.
Tapatalked... just Tapatalked...
If you're mainly looking for a way to detect NPEs then IntelliJ/Android Studio comes with NPE (and other exceptions) detection. It's based on a new set of annotations implemented in the latest SDK and is very accurate, much better than Eclipse's code analysis.
But honestly, the best tool to find bugs remains Logcat imo, it's verbose enough to find-out the origin of most bugs.
Hi All,
I'm a software developer, reasonably comfortable with compiling apps in Linux, though still got more to learn on inner workings of the full system.
I've been thinking about following the Linux from Scratch book for a while - and also about converting my Nook e-reader into a useful device for developing on when out im the sun.
I guess there are some significant challenges here - device trees and commercial secrets, perhaps some crypto keys used for signing update images to boot (I'm familiar with these problems, but not solutions or good workarounds).
What I'd really like is a good understanding of:
- what tool chain I need to setup
- What has been tried already and what the problems were
- any further help/datasheets that can get me going
I'd have posted this in the 'android development' area as the closest forum for what l'm trying to do, but apparently I'm not allowed until I've got my post count up - so I'm being forced to post in 'general'. If someone agrees and can move it, that would be great.
P.s. I have searched the xda site, but I'm not finding what I'm looking for. I'm sure it must be here somewhere, so any pointers/links on where it is would be appreciated.
SimonSimpson said:
Hi All,
I'm a software developer, reasonably comfortable with compiling apps in Linux, though still got more to learn on inner workings of the full system.
I've been thinking about following the Linux from Scratch book for a while - and also about converting my Nook e-reader into a useful device for developing on when out im the sun.
I guess there are some significant challenges here - device trees and commercial secrets, perhaps some crypto keys used for signing update images to boot (I'm familiar with these problems, but not solutions or good workarounds).
What I'd really like is a good understanding of:
- what tool chain I need to setup
- What has been tried already and what the problems were
- any further help/datasheets that can get me going
I'd have posted this in the 'android development' area as the closest forum for what l'm trying to do, but apparently I'm not allowed until I've got my post count up - so I'm being forced to post in 'general'. If someone agrees and can move it, that would be great.
P.s. I have searched the xda site, but I'm not finding what I'm looking for. I'm sure it must be here somewhere, so any pointers/links on where it is would be appreciated.
Click to expand...
Click to collapse
I have tried to get info on such things three times over 2 years for different devices, no one every seems to point me in the right direction, the most i have been able to find out is how to make compile cm and a little bit of how to customize roms, not to be a downer but i think the process is often so different for ever device and difficulties usually happen that the only people that build roms are people that have either have experience I n some form from their job, just edit existing source for cm(updating to a new version, customizing roms ect...) or have screwed with the stuff for years till the point that they just figured out alot of problems themselves. Wish a could find a good guide myself to atleast get the basic dependencies required for a device to boot together, if i could get something to boot the rest of the issues could be worked out with trial and error, boot noone on xda, Android authority, Reddit or cm's own forums goes into enough depth to make that possible.
Hi jaykoerner,
Thanks for your reply - good to know I'm not alone with my echo!
I've discovered some useful links if anyone wants to begin getting to grips with all this...
1. XDA Devs has a wiki (not sure how to find from the forum links...?)
http://forum.xda-developers.com/wiki/BN_Nook_Simple_Touch
2. There's a (atleast one) customized kernel (and probably a dev-tool chain) available on GitHub:
https://github.com/javifo/NST/tree/master/kernel -- including kernel compilation instructions
https://github.com/javifo/NST -- root of the repository.
3. Parallel to Raspberry Pi kernel compilation (so you may want to learn from that as it probably has more articles)
https://www.raspberrypi.org/documentation/linux/kernel/building.md
I'll post more when I next do something with the information (Still want to understand more on the android HAL)
Hope that helps someone!
SS.
SimonSimpson said:
Hi jaykoerner,
Thanks for your reply - good to know I'm not alone with my echo!
I've discovered some useful links if anyone wants to begin getting to grips with all this...
1. XDA Devs has a wiki (not sure how to find from the forum links...?)
http://forum.xda-developers.com/wiki/BN_Nook_Simple_Touch
2. There's a (atleast one) customized kernel (and probably a dev-tool chain) available on GitHub:
https://github.com/javifo/NST/tree/master/kernel -- including kernel compilation instructions
https://github.com/javifo/NST -- root of the repository.
3. Parallel to Raspberry Pi kernel compilation (so you may want to learn from that as it probably has more articles)
https://www.raspberrypi.org/documentation/linux/kernel/building.md
I'll post more when I next do something with the information (Still want to understand more on the android HAL)
Hope that helps someone!
SS.
Click to expand...
Click to collapse
My initial thought was that toolchain should match the underlay Linux kernel of Eclair (2.6.x.y) for us to be sure it could be run on NST. This info that I still have to search through is certainly helpful. Thanks!
SimonSimpson said:
I guess there are some significant challenges here - device trees and commercial secrets, perhaps some crypto keys used for signing update images to boot...
Click to expand...
Click to collapse
Neither the NST or the newer glows use device trees.
In the Glows this is all handled by the custom ntxconfig which allows simple configuration.
For building Android apps, you use the straight Android SDK, possibly also the Android NDK (for native code).
You'd also use the NDK for building command line utilities.
I've never built a kernel from scratch, but I have binary modified/patched them.
There is the simpler bit of patching system image ramdisks which can be conviently handled by my imgutil.exe in the signature.
If you want to do audio, you really are better off with the Glow4 (7.8") which actually supports it.