![]() ![]() Run the application and choose a running android device and install the application on it and verify the results.įollowing is the content of the modified MainActivity.java. Modify the res/menu/display_contact.xml to add necessary menu componentsĬreate a new menu as res/menu/mainmenu.xml to add the insert contact option Modify the res/values/string.xml to add necessary string components Modify the res/layout/activity_display_contact.xml to add respective XML components Modify the res/layout/activity_main to add respective XML components Modify src/MainActivity.java file to get references of all the XML components and populate the contacts on listView.Ĭreate new src/DBHelper.java that will manage the database workĬreate a new Activity as Displa圜ontact.java that will display the contact on the screen You will use Android studio to create an Android application under a package. ![]() To experiment with this example, you need to run this on an actual device on which camera is supported. It creates a basic contacts applications that allows insertion, deletion and modification of contacts. Here is an example demonstrating the use of SQLite Database. Public class DBHelper extends SQLiteOpenHelper It automatically manages the creation and update of the database. This method returns true if the cursor is closed and return false otherwiseįor managing all the operations related to the database, an helper class has been given and is called SQLiteOpenHelper. This method returns the current position of the cursor in the table ![]() This method returns the total number of rows in the cursor This method returns the array of all the column names of the table. my cursor contains all of the values - including a taskId with value 1. Cursor cursor db.rawQuery ('SELECT FROM Task where taskId 1 ', null) However the cursor is returned empty, a taskId with value 1 exists. This method returns the name of the column by specifying the index of the column I am trying to get data from my SQLite database in Android using this query. This method returns the index number of a column by specifying the name of the column This method return the total number of columns of the table. Another method that also does the same job but take some additional parameter is given below This will insert some values into our table in our database. Mydatabase.execSQL("INSERT INTO TutorialsPoint VALUES('admin','admin') ") Mydatabase.execSQL("CREATE TABLE IF NOT EXISTS TutorialsPoint(Username VARCHAR,Password VARCHAR) ") We can create table or insert data into table using execSQL method defined in SQLiteDatabase class. This method is similar to above method but it takes the File object as a path rather then a string. OpenOrCreateDatabase(File file, SQLiteDatabase.CursorFactory factory) ![]() This method is equivalent to openDatabase method. It not only opens but create the database if it not exists. OpenOrCreateDatabase(String path, SQLiteDatabase.CursorFactory factory) It is similar to the above method as it also opens the existing database but it does not define any handler to handle the errors of databases OpenDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags) The common flags mode could be OPEN_READWRITE OPEN_READONLY This method only opens the existing database with the appropriate flag mode. Once loaded, modify the code to add the appropriate data members and methods: package (String path, SQLiteDatabase.CursorFactory factory, int flags, DatabaseErrorHandler errorHandler) Once created the Product.java source file will automatically load into the Android Studio editor. From the popup menu, choose the New -> Java Class option and, in the Create New Class dialog, name the class Product before clicking on the OK button. Within Android Studio, navigate within the Project tool window to app -> java and right-click on the package name. Essentially, this class can be thought of as representing the database model. Instances of this class can then be created within the activity and database handler and passed back and forth as needed. This is actually a very simple class capable of holding product ID, product name and product quantity values, together with getter and setter methods for accessing these values. In order to implement this interaction in a structured way, a third class will need to be implemented to hold the database entry data as it is passed between the activity and the handler. SQLite supports all the relational database features. Android comes in with built in SQLite database implementation. SQLite is an opensource SQL database that stores data to a text file on a device. The database handler will be a subclass of SQLiteOpenHelper and will provide an abstract layer between the underlying SQLite database and the activity class, with the activity calling on the database handler to interact with the database (adding, removing and querying database entries). How to use SELECT Query in Android sqlite - Before getting into example, we should know what sqlite data base in android is. Once completed, the application will consist of an activity and a database handler class. ![]()
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