I would like to build some simple application - for example Todo list - and I am thinking about the problem and its solving - how can I to store data in my own application on Android platform?
I should to use some text file, xml file or some database? What will be better for beginner on this field?
You'll have a VERY hard time getting anywhere with Android if you don't read through their website/dev resources. I would highly recommend visiting their site.
As far as data storage is concerned, that varies based on your need. Explained here
My suggestion is to use SQLite that comes with Android. http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html
In my opinion, a SQLite database seems most appropriate for this kind of application. There is lots of support for using the SQLite database in conjuction with ListViews (which I imagine you'd want to use in your to-do list app).
In case you haven't already checked it out, see the page on the developer site:
http://developer.android.com/guide/topics/data/data-storage.html#db
Theres a few ways you can store data. I've created a few applications thats store data using shared preferences
They're quite handy for storing strings, ints, bool values etc. However if you have a large scaled application, that requires better database management, I would look into sqlLite.
Android has supported classes and functions to help access/store the information.
Theres a good tutorial on the android site called notepad that takes you through how to use sqlite.
That should get you started :)
Look at this Thread klick
Edit: its cool for less data, if you want to store and browse lots of data, you should use as SQLite Database
Using a file, database or xml based depends entirely on what kind of application you are building. For eg: If you parse an XML feed and store the results back in an XML file - it totally defeats the storage purpose!
Databases are used to store structured and related content like - news feed results, email client data, etc.
Files are more used for storing raw / binary content like storing images, attachments, etc.
BTW, if you are a beginner - you should try all of them! :)
Hope this helps!
Related
I have read through the Android Storage Options and I have a question that I haven't been able to find the answer to:
Should I use SQLite to store my data or should I use a JSON object that is written to a file?
Requirements:
Store (up to) a few hundred instances of the same object. Each instance will be somewhat complex, storing reference to images, smaller objects, etc. The data will be stored locally, with the option of cloud backup. All the data will be loaded on startup and saved when manipulated by the user.
The reason I ask this is because I don't have a lot of data to store - for a SQLite database there will probably never be more than a few 100 rows, which makes me think SQL is overkill.
Also, exporting my data to a JSON file will allow me to easily import/export from different device platforms (I already do this on iOS).
Or, maybe there's a better option? If there was an NSCoding type library for Android I would probably use that.
Any opinions are helpful.
Thanks!
From the presented so far, storing in files will be more advantageous.
Considering that each "unit" is less than 16 attributes, a json file with short identifiers will likely generate a larger file representation than the SQL representation equivalent.
However, the local file manipulation will allow for easier interactions, as well as easier backing up/down.
Also, the File class is simple enough to generate less issues when compared to SQL.
Finally, given the choices, you are going to have to evaluate the operations used.
If you are going to compare the data, then SQL is likely to go faster, but if you are just inputting/outputting each data as a separate object, than files are going to be as fast as SQL.
Finally, please, particionate your objects, do not create just 1 file with all the info.
I have read through the Android Storage Options and I have a question
that I haven't been able to find the answer to:
Should I use SQLite to store my data or should I use a JSON object
that is written to a file?
You need to analyse your requirement again.
maybe there's a better option?
It depends upon your requirement.
if Your requirement is fixed to simply storing and retrieving then you can have a look on tinnyDB, which is basically using the SharedPreferences as storage mechanism. But if you need case base based selection/query of data then you should go with SQLite.
I have been asked to create a tiny android app.
In everyday work i code for .NET and I have no experience connected with Android, but as it is a really small app I guess it's going to be a good experience rather than something hard.
The core of the app would be a small database (probably XML, unless somebody suggest better solution) that would contain categories, names of the institutions assigned with each category and logo (not very high resolution I guess a single file would be <100kB) of the institution.
The database also would not be very big - I expect not more than 1000 records in total. The DB has to be totally offline and local, it cannot require Internet access when operating.
The model I assume would be to ship new version of the application when the database changes (which is not going to be very frequent).
What is the best way to deal with these requirements?
My first idea was to create an XML file that would contain the records and link to the image. The XML and all the images linked to it would be stored in single file (preferably zip) that would be stored in app resources. This is very good as it is going to be very easy to update the database.
The second idea that somebody suggested me would be to use SQLite and store images in BLOB. In general I have read that it isn't a good idea to store images in database directly, and I am afraid if it's going to be possible to meet all requirements mentioned above.
Mostly I have no idea how to update the database easily and attach it to new version of application.
Any suggestions?
I would be grateful for any response.
I wouldn't go about using XML to save your data and by no means zip anything.
I think your way of thinking is ok, but you're making things really complicated for yourself.
Seeing as you're used to .NET I suppose you're also pretty confident with SQL, so I'd suggest you have a look at how to use the built-in SQLite database in Android.
If you would go the XML route you'd have to serialize and de-serialize the XML file over and over again and then parse the XML. Ok you don't have a lot of data, but searching inside an XML file with at least 1000 nodes would be slow in comparison to the performance of a database.
Also upgrading an existing SQLite database is not that hard - Android has methods for that (onUpgrade coming from the SQLiteOpenHelper).
As to saving images I'm assuming that you won't fetch new pictures from the Internet, so it would be best just to store them in the drawable folder of your app (be mindful of different screensizes) and then reading them into an ImageView when needed. To figure out what image should go for what institution I would store either the image name of each image in the SQLite database or store the resource id for each image in the database - for instance R.drawable.myawesomepictureformyinstitution.
I know my answer is somewhat "superficial", but your question is also somewhat "broad" and hard to answer without me actually writing most of the code, and that's not my intention ;-)
Hope this helps - let me know if anything is unclear.
In my android application I have to store some application settings and some user information within the phone.
I can go for the shared preference option explained in this DOCUMENTATION.
But wondering if I can store data as objects wise within the phone. I found this Stackoverflow Question regarding saving serialized objects in files and bit not sure of any issues if I go with this way to store persistent data.
Also would like to know what the best way to deal with insert/delete/update and read with XML files in android. Would appreciate any guidance. Thanks in advance...!!!
If it is only a small amount of data you need to store, then go with the built-in shared preferences, that is what the functionality is there for. SQLite and OrmLite are a bit heavyweight in this situation IMO. Even if you want to handle the data as Objects; in which case I would serialise to / deserialise from JSON or XML stored in text files and handle the insert/update/delete on the deserialised objects in your model.
If you want to persist some objects I think you should use SQLiteDatabase, it would be a more cleaner solution than using serialization in files. You will indeed need to write some extra code for your Database but you will end up with a cleaner implementation in my opinion. You could also be using OrmLite for Android which is pretty robust and easy to use if you have some basic orm knowledge.
I have some really huge data that is required for my android app. I've put it into a sqlite db now. Roughly it is 39k rows and 5 columns. I want this data to be available for my app.
I'm kind of confused as to how I ship my app with it. i can ship the db file with it like discussed in this thread. or I can somehow create XML out of that data and ship it along. But the XML would be really huge. So what is the right way of doing it?
I do not want to download it after user installs the app. That'd be my last option if there are no better clean ways of doing it.
This should help you.
http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/
Basically just ship the database with your apk file.
I think shipping your DB could make some problems with compatibility.
Maybe it will be better to use GZIP'ed SQL code bundled to your .APK?
Or instead of XML for intermediate representation you can use google protobuf, which is most effective data representation format(Also, if you have a lot of strings, you can use it in combination with GZIP).
Check the example here to achieve this functionality.
I'm making a game to run on android. So I want to store player names and the winner, which I will also list up in a view. What is the best way to do this, use a database or write to a file (if so, what type, xml?). I have to be able to add data after every completed game, and the size won't be so large. What would be the best solution?
IMO, using a SQLite database would be the most straightforward. You don't have to worry about the xml parsing that goes along with an xml file. Additionally, the data your storing seems to have a natural relationship that would be conducive to a SQLite schema. For more information about how to use SQLite in Android, see the data storage documentation here.
SQLite is great if you have database concerns and want that sort of data lookup.
However, if you really want to do it Simply with XML then you can in Android.