I want to use sharedpreferences in my login form, but i also want keep XAMPP as my main storage. What is the best data storage when I want to do my app in offline mode?
Yes, you're allowed to mix and match any type of data storage you wish because none of them were designed to be in conflict with each other.
However, it's a good idea to understand what type of data storages is available for you to use, because different types of storages has different benefits and drawbacks.
SharedPreferences is a great way to store a user's preferences, or simple data with a single value. It's great for storing a user's preferences because when creating Settings, it's extremely common to use Preferences which directly reflects the values within your SharedPreferences. However, due to it's design, SharedPreferences isn't a good idea to store large amounts of data or dynamically created data.
For that, it's better to use a database and you're free to use any type of database you wish. But for offline mode, it's best to use the SQLite Database that's offered by Android by default.
However, if you do want to use XAMPP, it's not uncommon to see developers who store their full data in an online database, but cache a few data within a local database like SQlite.
Therefore, there's zero conflicts among data storage options, so mix and match to what benefits your app's design best.
If you want to store data in locally then you can use SQLite Database and yeah XAMPP is whole different thing to store data for this you need to create APIs to communicate with database.
You can also use Sharedpreferences for storing the data but Sharedpreferences will store data with the key-value pair only.
But you can use both for different different purposes for the same app
Related
In my android app I have about 100 places (maximum will be 200). I want to allow the user to mark each place as visited and store this selection.
So the user can mark/unmark that he already visited some places/cities.
Is it a good idea if I store the values as SharedPreference?
My code:
SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("London", "1");
editor.commit();
and next time when user marks another place then:
editor.putString("Paris", "1");
I am asking due to amount of possible places to be stored there, which will be maximum 200 in my case. I am usually using this kind of storage just to store some settings or so, but I think this is an easy way to store the values in my case too, I don't want to use database or anything similar for storage.
Whether this is a good idea or not depends on your requirements and expectations. If you store the data like this, it will work for sure, but, there will be some limitations:
It might be complicated to show a list of places to the user. If you store some other data to shared preferences you will need a way to distinguish places from other data. In this case you'll probably need to add a prefix to all your keys, such as "place_London", "place_Paris", etc.
You are relying on English key names so you might have issues with localization if you support other languages
It will be much harder to support versioning and scalability. E.g. if later you have an entity called "Place" and it has more information than just a name with a flag, then it will be much harder to keep it in shared preferences. E.g. if at some point you want to add a corresponding country name to all places, what do you do?
I think in this scenario you actually DO want to use database. It will pay off.
SharedPreferences is a key/value way to save data. I think it is not appropriate to save large amount of structured data as you have to define a key for each value you have.
Using SQLite might be a better option for your case.
You should switch to a more reliable way of storing data in storage instead of using SharedPreferences.
Sqlite is good option but if you don't like to write SQL Queries and want a solution where you want to store data in your storage, Realm is an amazing alternative.
Although before implementing please read more on the pros and cons of using realm. You can read more about Realm here :-
realm.io
Realm vs Room vs ObjectBox
The android documentation has the following options below but does not explain what circumstances each is best for. What are the pros and cons of each method? e.g. Under what conditions would SQL be better than Shared Preferences?
Shared Preferences
Internal Storage
External Storage
SQLite Databases
Network Connection
Different Storage options in Android
Content Providers
Consider the structured data added to the device from application1 is
not accessible to another application2 present in the same device but
the profile photo added to the device by application1 is available to
the application2 running in the same device
Consider android device as a city, the applications in it are the
houses in the city, people in the houses(application) are the data.
Now content provider is like an broker in the city(android device).
This broker provide access for the people in the city for finding
different houses referring as the content provider in the android
device provide access for the data in the device for different
applications.
Shared Preferences
Consider I have an App say a Face book App which I use to log in to
my account.
Now the very first time I enter my username and password to get
access to my account. Say I log out of the application an hour later
again I use the same Face book App to login again to my application.
I have to enter username and password again to login to my account
and I set a theme to my application and other settings on how my app
looks in my current phone
This is un-necessary because consider I am using my phone to login to
the application. So I will always use my phone to login again and
again, thus entering my credentials again and again is more work
shows it’s not a user friendly app
Shared Preferences is very handy in such scenarios where I can use
its feature to share my data in a xml file Which physically exists in
the Android app installed in my phone which is not destroyed even if
the app is closed. Here we can save user preferences data of the
current application.
As a result next time I open my app in my phone I can see the data
automatically filled in the necessary fields and the settings are
File Storage
In Android we can use the device storage space to store the data in
it for the applications. The type of data involves things such as a
text file, image file, video file, audio file etc.
As seen in the figure as we can see that there are two places we can
do this. One way is to write the raw files into primary /secondary
storage. Another way is to write the cache files into the
primary/secondary storage.
There is also difference between storing raw data and the cache data,
the raw data once stored in memory by user has to be explicitly
deleted by the user explicitly otherwise it would exist till then.
Cache data stored in memory is not a permanent data because the
system automatically deletes it if it feels there is shortage of
memory.
Internal Storage:
Consider a user in an application has stored data in internal
storage, then only that user of that application has access to that
data on the mobile and that data is automatically deleted when the
user uninstalls the application. Speaking of which internal memory is
private.
The apps internal storage directory is stored using the name package
name in a special place in the android file system.
Other apps or users of current app have no access to the file set by
a particular user and a particular app unless it is explicitly made
available to the user for readable/writable access.
SQLite
Sqlite is used to store more structured data locally in a mobile
where the android app is running. Structured data involves as of
which shown in the figure like a student’s information in the form of
rows and columns.
Sqlite offers similar functionality like Mysql and oracle but with
limited functional features. Some of the things involve performing
query operations on tables. There are features though like creating
views but also some features are not available like stored procedure.
Sqlite is very helpful in storing complex and large data which can be
downloaded once and can be used again and again until the application
is running. When the application is closed the sqlite database is
also destroyed.
Putting all the pieces together
Shared preferences are good for storing ... an application's preferences, and other small bits of data. It's a just really simple persistent string key store for a few data types: boolean, float, int, long and string. So for instance if my app had a login, I might consider storing the session key as string within SharedPreferences.
Internal storage is good for storing application data that the user doesn't need access to, because the user cannot easily access internal storage. Possibly good for caching, logs, other things. Anything that only the app intends to Create Read Update or Delete.
External storage. Great for the opposite of what I just said. The dropbox app probably uses external storage to store the user's dropbox folder, so that the user has easy access to these files outside the dropbox application, for instance, using the file manager.
SQLite databases are great whenever you are going to use a lot of structured data and a relatively rigid schema for managing it. Put in layman's terms, SQLite is like MySQL or PostgreSQL except instead of the database acting as a server daemon which then takes queries from the CGI scripts like php, it is simply stored in a .db file, and accessed and queried through a simple library within the application. While SQLite cannot scale nearly as big as the dedicated databases, it is very quick and convenient for smaller applications, like Android apps. I would use an SQLite db if I were making an app for aggregating and downloading recipes, since that kind of data is relatively structured and a database would allow for it to scale well. Databases are nice because writing all of your data to a file, then parsing it back in your own proprietary format it no fun. Then again, storing data in XML or JSON wouldn't be so bad.
Network connection refers to storing data on the cloud. HTTP or FTP file and content transfers through the java.net.* packages makes this happen.
SharedPreferences is mainly for application-specific settings that you can access via your Settings menu - like application settings. It's a good idea to keep everything simple here - mostly boolean flags, short strings, or integers. SharedPreferences data persist on device reboot, and are removed along with app uninstallation. Data is saved as a key-value pair.
Internal Storage is mostly used for larger non-persistent data storage. You utilize internal storage if you want to process an image, a short video clip, a large text file, etc. But you don't store the processed data in the internal storage - its function is more like a CPU's RAM. The amount of available internal storage for your application depends on the device, but it's always a good idea to keep anything under 1MB. Data is referenced via its file path.
External Storage does not only refer to the SDCard storage, but for higher-end phones, this can mean internal mountable storage (like in the Galaxy Nexus or S2). This is where you store the large video files, the high-resolution images, and the 20-megabyte text file you want to parse in your application. This is also a place to store data that you want shared across devices if you swap sd cards. Data is also referenced via its file path.
SQLite Databases is where you'd store pretty much anything you want in a regular database - with the advantage of organizing things into tables, rows, and columns. It works best with things that you want displayed in the UI as lists - the best example would be the great invention knows as the CursorAdapter. Data stored here also persist on device reboot, and are removed with app uninstallation. You can also share data across applications with sqlite db if you hook it up to a ContentProvider. Data is accessed using a Cursor, where you can call methods as if you're executing sql statements.
Network Connection is not really a data storage technique, but can be a way of persisting data for a specific user provided the device is connected to the internet, using some sort of authentication. You have to balance out between downloading data every time the app needs it, or having a one-time data sync, which would ultimately lead to another of the storage options mentioned above.
Shared preferences are key/value pairs, nothing more. So if you want to keep track of say, students and their test score, it really won't work well for that.
A database is just that, a database. You can define as many columns (and tables) as you need to get the job done.
If it's preferences for your app, use shared preferences (almost any preference I can think of can be done that way), if it's anything else more complicated, use a database.
Im saving datas from my db/user into a gson formated ArrayList in SharedPreferences. Now my question :
Is it safe to save these datas (or data in general) into Sharedpreferences. Are users able to read these gson Arraylists out ? Maybe from SD card ,in a folder or somewhere else.
Thank you !
They are stored as xml files in your app directory, with permissions that allow only your app to access them. But on rooted device they are easily accessible. If you are concerned with security then you may use encryption, those projects might be usefull to you:
https://github.com/rtoshiro/SecureSharedPreferences
https://github.com/sveinungkb/encrypted-userprefs
still those projects does not give you 100% guarantee, hacker may decompile your apk and find keys used to encrypt shared preferences. So if your data is of use only for short time then remember to remove it from your device once user has finished using it. You may for example keep data on server and download it only when needed, caching locally only for short time - when its needed.
SharedPreferences is just a file located in phone private memory. So user can't access it but root can. Root can everything and many users have root's nowadays. You shouldn't store fragile data there
Android SharedPreference security
You can read all shared preferences Data
The SharedPreferences class provides a general framework that allows
you to save and retrieve persistent key-value pairs of primitive data
types.
To see the information in the store you need to know the important thing from the data. This will make reading through the information super easy. But as simple as it's to keep a tiny bit of data as difficult it's to keep and browse large structured data since you need to define key for every data, in addition you can't really search inside the data except you've got a certain concept for naming the secrets.
Please read Android SharedPreference security
I'm making a simple GPA android app. The user can input their grades and class names for each semester. How would I then store each of these semesters so that they can always be pulled up in the app? I might also need to store random variables that are alone.
I've briefly looked at options such as Shared Preferences, Internal Storage, and others. What option is the best for my needs? Please explain why. Thanks!
Here is Explanation...
Shared preferences are good for storing ... an application's preferences, and other small bits of data. It's a just really simple persistent string key store for a few data types: boolean, float, int, long and string. So for instance if my app had a login, I might consider storing the session key as string within SharedPreferences.
Internal storage is good for storing application data that the user doesn't need access to, because the user cannot easily access internal storage. Possibly good for caching, logs, other things. Anything that only the app intends to Create Read Update or Delete.
External storage. Great for the opposite of what I just said. The dropbox app probably uses external storage to store the user's dropbox folder, so that the user has easy access to these files outside the dropbox application, for instance, using the file manager.
SQLite databases are great whenever you a lot of structured data and a relatively rigid schema for managing it. Put in layman's terms, SQLite is like MySQL or PostgreSQL except instead of the database acting as a server daemon which then takes queries from the CGI scripts like php, it is simply stored in a .db file, and accessed and queried through a simple library within the application. While SQLite cannot scale nearly as big as the dedicated databases, it is very quick and convenient for smaller applications, like Android apps. I would use an SQLite db if I were making an app for aggregating and downloading recipes, since that kind of data is relatively structured and a database would allow for it to scale well. Databases are nice because writing all of your data to a file, then parsing it back in your own proprietary format it no fun. Then again, storing data in XML or JSON wouldn't be so bad.
Network connection refers to storing data on the cloud. HTTP or FTP file and content transfers through the java.net.* packages makes this happen.
Considering this i suggest you to use Sqlite especially in your case.
Best luck
it depends on your need, some times you use all options in the same app,
for example : the best way to store grades and classes is using database, in android SqlLite database.
and for storing some variables values like username and password you just need to use shared preferences.... at least this is my policy in my apps.
SQLite will be the best for your scenario.
As you can create well formatted Tables with desired columns. Either you can use pre-developed database or you can create tables on the go.
Actually i want to know how to store data from my app in the device so that i can review the store data when i run the application again..
means in simple terms i want to say that suppose i have text box where i write some information..now when i click the submit button, this information will be save,so that when i open the application the stored data should be appear in the text box..
In all terms i want to say that i just want to stored data in the way that we are using database for storing data..so please anyone suggest me how that can be done in android.
if possible show with an example
Regards
Anshuman
If you have to store small amount of data, you can use SharedPreferences in Android.
If the data that you have to store is big/complex enough, try using SQLite database.
Still need help?
UPDATE: There's a tutorial that I wrote to demonstrate how to use SQLite database. check it out here. Although it copies existing database into device's memory, but other versions of it, which create database through code can also be devised from it.
A better tutorial is here : http://www.vogella.com/tutorials/AndroidSQLite/article.html
1) If you want to store data in table format then you can use SQLite database in android
2) If you don't want to store data in table format then you can store in SharedPreference
more info about SharedPreference here and here
Android comes with a built in SQLite database that you can use. I advice you to go trough this notepad tutorial. It teaches the basics of using Android SDK including different states of the android application as well as how to use SQLite with Android.
For storing simple key = value pairs, you can use Properties.
For data storage as in a database, you can use sqlite on android.
Android provides several options for you to save persistent application data. The solution you choose depends on your specific needs, such as whether the data should be private to your application or accessible to other applications (and the user) and how much space your data requires.
Your data storage options are the following:
Shared Preferences
Store private primitive data in key-value pairs.
Internal Storage
Store private data on the device memory.
External Storage
Store public data on the shared external storage.
SQLite Databases
Store structured data in a private database.
Network Connection
Store data on the web with your own network server.
Data Storage