eclipse/ has the example in the eclipse format (no longer updated). otherwise all examples are using Android Studio.
legacy/ these are examples that are no longer updated.
Preference Examples:
PerferenceDemo uses the preference fragments to save user preference data. Note, there are no support libraries used for fragment or preferences. Also, this is for API 16+, for older versions, see the legacy directory example. This example will maintained but not updated.
SupportPerferenceDemo (java) uses the androidx preferences fragments to save user preference data. This is a translation of the PerferenceDemo to the newer androidx versions.
SupportPerferenceDemo_kt (kotlin) uses the androidx preferences fragments to save user preference data. This is a translation of the PerferenceDemo to the newer androidx versions.
Shared Preference Examples:
saveDataDemo (java) shows an example of using the instance bundle, the shared preference system to store data, and viewmodel for when the app is rotated, and for long term vs short term data storage.
saveDataDemo_kt (kotlin) shows an example of using the instance bundle, the shared preference system to store data, and viewmodel for when the app is rotated, and for long term vs short term data storage.
DataStoreDemo (java) shows an example of using the newer dataStore method that is supposed to replace shared prefence system. it's harder and more complex to use, then shared preferences. Also the java code does not match the kotlin code, but is the same functions.
DataStoreDemo_kt (kotlin) shows an example of using the newer dataStore method that is supposed to replace shared prefence system. it's harder and more complex to use, then shared preferences. Also the java code does not match the kotlin code, but is the same functions.
File system examples:
fileSystemDemo shows how to read/write to local private and public directory. The external has been removed, since it won't work in API 30 (see legacy). A new example will be needed for the sdcard, when I can find documentation that actually works (I looking at you google/android, poor documentation).
fileSystemMediaStoreDemo show you how to access the DCIM and pictures directory (easily changes to video). This allows you to access the media on the SDcard, but any other file types.
fileSystemMediaStoreRecAudioDemo This example uses the mediastore to record and play files on the music directory. actually in a subdirectory, music/recording. There is a picker for filenames and to choose which files to play. Note, you will need to record at least one file in order to play something.
ScreenShotDeetectorDemo This is a first attempt out detecting screenshots using a content observer. It works pretty well, tested on a pixel 4a for screenshots with the buttons. fails to detect using the launcher screenshot method.
Sqlite Examples:
Note Room Examples are in the Architecture repo
sqliteDBDemo (java) an SupportSQLiteDatabase is created and used. The data is displayed via a recyclerview. While the code has
insert, update, delete, and query. Only the query and insert methods are called by this example.
sqliteDBDemo_kt (kotlin) an SupportSQLiteDatabase is created and used. The data is displayed via a recyclerview. While the code has
insert, update, delete, and query. Only the query and insert methods are called by this example.
sqliteDBViewModelDemo (java) uses a SupportSQLiteDatabase, enters data and displays it via a recyclerview. It uses a ViewModel to update the display when data is added. It also could delete and update data in the database, but the example does not actually use them.
sqliteDBViewModelDemo_kt (kotlin) uses a SupportSQLiteDatabase, enters data and displays it via a recyclerview. It uses a ViewModel to update the display when data is added. It also could delete and update data in the database, but the example does not actually use them.
lvCursorDemo show how to use cursoradapters with listview and explistview.
Content Provider Examples:
ContentProDemo shows how to create a simple context provider and how to access it. Also has an example of accessing the contacts provider.
ContentProSQliteDBDemo shows how to create a content provider using a SQLite database. displays in a listview, recyclerview and a spinner.
ContentProviderRemoteDemo connects to a "remote" content provider. either the ContentProSQliteDBDemo or ContentProviderRoomDemo in Architecture repo. It then will display the data in recyclerview and can add data via a FAB.
These are example code for University of Wyoming, Cosc 4730 Mobile Programming course and cosc 4735 Advance Mobile Programing course. All examples are for Android.