I'm working on a Java based Android Project where I'm using sharedPreferences to store the data.
I want to use Preferences DataStore in my project but unable to find any good example to take reference. Please suggest any reference examples in Java to implement preference data store in Android or how to migrate from shared prefs to DataStore.
I tried to go through developer documentation, but couldn't understand the example provided
It is very straightforward to migrate from sharedPreferences to dataStore.
Pass the old SharedPref name and the migration happens automatically.
private val dataStore: DataStore<Preferences> =
context.createDataStore(
name = "data",
migrations =
listOf(SharedPreferencesMigration(context, "shared_preferences_name"))
)
Related
Need to implement DataStore to my android project in java.
I'm following this document:
https://developer.android.com/topic/libraries/architecture/datastore?hl=pt-br#java
but is not working.
I can only find examples in Kotlin.
Can someone show me a simple example of using DataStore Preferences in java?
Thanks!!!
As I saw there no example present in java for dataStore so what you can do just go through this codelab which is in kotlin mean to follow the step but use java instead of kotlin, I hope this will help you.
DataStore Example: https://developer.android.com/codelabs/android-preferences-datastore#7
Use above link to learn dataStore and use below to convert kotlin code of data Store in java by using RxJava
java link: https://developer.android.com/topic/libraries/architecture/datastore?gclsrc=aw.ds&&gclid=Cj0KCQjwp86EBhD7ARIsAFkgakg-4Xc0UsX_xgNZmeSeNdZfTuoMoZ4JPUuZUyJq7dUOAV_JSY029GoaAgCHEALw_wcB#preferences-create
I am making a school management project and I want to add a setting panel in my project, but unable to determine how to store the settings for a project in java?
how can i make it possible?
Easiest way would be with the Preferences API. You can save and load things without worrying how they're stored.
You can use many different things to store persistent data. Persistent means data will be stored after your app stopped running.
XML file:
JAXB
A database like: JAVA SQL
JSON file: JSON API
Java Properties: Properties Docs
However I recommend you JAXB, because I think it is the easiest way.
I was thinking of making an Android Application, a Cook Book for example, that can be semi-online. Meaning the Application doesn't have to be online but it can be. An example would be that the users want to share recipes with other people on the network.
I'm going to use Java as the backend of the system, so I was thinking of using JDBC. Is that possible?
In android you can use sqlite database for your data storage or you can also use and Shared Preference it is are like java properties follow beloow link for quick reference of all...
for sqlite
http://www.vogella.com/articles/AndroidSQLite/article.html
for Shared Preference
http://www.vogella.com/articles/AndroidFileBasedPersistence/article.html
You cannot use jdbc in Android.For apps requiring your data to be stored in some persistent storage,Android devices comes with in built SQLITE database where you can insert,update,delete and perform various operations on table created in it.
You can ask if you have any further queries.
Say, I have a pretty simple Java application that needs the way to store some user settings. XML is not a really good solution, since I want to store them in binary form. So, what would be the best solution in this case, embedded database (such as Apache Derby) or just plain old serialization?
I know that these are two completely different things, but both allow to persist some application state. So what would you chose, and why?
Edit
As far as storing simple user preferences go, .properties or xml files are fine, I agree with you. But what if I want to store passwords, or some application-specific data?
User settings are typically stored as
properties, using the properties file format
properties using the XML format
preferences, using the Preferences API. This has the advantage of storing and reading user and system preferences for you, without having to think about where to store them, etc. See http://download.oracle.com/javase/1.4.2/docs/guide/lang/preferences.html
As Apache Derby is an embeddable relational database, it makes sense to use it for storing and manipulating relational data. Using an embedded db for persisting a few user settings only is a bit overkill.
If it were me, I would use a simple key/value pair serialization for persisting user settings.
I'm using the Google app engine and JDO. What is the best way to update a JDO class definition without having to wipe the data store contents first?
I'm not sure if this is specific to JDO on GAE, but I noticed that when I simply change the name of one of my persistent fields from svotes to votes, an exception is thrown (java.lang.NoSuchFieldError: svotes).
I expect once my site goes live I might want to make some changes to my JDO class definitions, such as adding a field or something. Any suggestions for how to update the data definitions without having to wipe the database?
Have you tried some of the methods mentioned here?
Apparently Google has a python related article about updating the schema: http://code.google.com/appengine/articles/update_schema.html. The guidelines can be applied to java too.