![]() Add two Plain Text fields, three Buttons, and a TextView to the layout and position them as shown in Figure 38-1: Figure 70-1Ĭhange the hint property of the Plain Text views to “name” and “phone” respectively and remove the default “Name” text property. Open the activity_main.xml file and delete the default TextView component. The full book contains 99 chapters and over 842 pages of in-depth information. Purchase the fully updated Android Studio Iguana Kotlin Edition of this publication in eBook or Print format. You are reading a sample chapter from an old edition of the Android Studio Essentials – Kotlin Edition book. Use the steps in An Overview of Android View Binding to enable view binding for the project. Before clicking on the Finish button, change the Minimum API level setting to API 33: Android 13 (Tiramisu) and the Language menu to Kotlin. Start Android Studio, select the New Project option from the welcome screen and, within the resulting new project dialog, choose the Empty Views Activity template before clicking the Next button.Įnter SQLDemo into the Name field and specify as the package name. The customer ID column will act as the primary key and automatically be assigned and incremented by the database management system. Each record in the database table will contain a unique customer ID, a customer name, and the customer’s phone number, corresponding to column names “customername” and “customerphone”, respectively. The name of the database file will be customerDB.db, which, in turn, will contain a single table named customers. ![]() The idea behind this application is a simple contact database containing customer names and phone numbers. The example project is a simple data entry and retrieval application that allows users to add, query, and delete database entries. In this chapter, we will create a project using SQLite databases to store and retrieve data. if distinct is passed as true Cursor data set will not have any duplicate row.The chapter entitled SQLite Databases in Android Studio covered the basic principles of integrating relational database storage into Android applications using the SQLite database management system. Most of the parameters in query overloaded functions are optional except from table and distinct any of other parameters can be passed as null. public Cursor query (boolean distinct, String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy, String limit).public Cursor query (String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy).public Cursor query (String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy, String limit).It returns Cursor object so Cursor is a result-set with queried data, it provides different functions really helpful while reading data.įollowing are some overloaded query functions: query() method is overloaded with different set of parameters. SQLiteDatabase class provides query() method to read data from table. Read(select):Reading from a database table is bit different from other functions like insert,update and delete. Important Note: If you want to remove all rows and require count of deleted ones also then pass 1 as whereClause. delete function will return number of affected row if whereClause passed otherwise will return 0. Here whereClause is optional, passing null will delete all rows in table. Public class SqliteManager extends SQLiteOpenHelper ĭb.delete( "Items", whereClause, whereArgs) Whenever we need to create a database we have to extend SQLiteOpenHelper class as follows: /**A helper class to perform database related queries*/ SQLiteOpenHelper is an abstract class with two abstract methods onCreate(SQLiteDatabase db) and onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) and many more database helpful functions. One writing raw queries and another is using parameterized functions or we can say parametrized queries.Ĭreate: Creating a database is very simple in android by using SQLiteOpenHelper class. While using SQLite there could be two different ways to perform different operations like create, read, update and delete. ![]() Android os has its own implementation to perform CRUD (Create, Read, Update, Delete)operations, so Android provides set of classes available in android.database and packages. SQLite is a structure query base database, hence we can say it’s a relation database. ![]() Android provides different ways to store data locally so using SQLite is one the way to store data. ![]()
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