Implements all optional list operations, and permits all elements, including null.
SQLite is one way of storing app data.
It is very lightweight database that comes with Android OS. In Android, integrating SQLite is a tedious task as it needs writing lot of boilerplate code to store simple data. Consider SQLite when your app needs to store simple data objects. In this article we are going to learn basics of SQLite database with a realtime example of Notes App.
The app will be very minimal and will have only one screen to manage the notes. Below are the screenshots of the app. Creating New Project 1. The RecyclerView will be used to display the Notes in list manner.
Add the below resources to colors. Below is the final project structure and files we gonna need. We also need a model class to create Note objects to manage the notes easily. Under database package, create a class named DatabaseHelper. This class holds the database related methods to perform the CRUD operations.
In this method, we execute the create table sql statements to create necessary tables. You have to take care of database migrations here without loosing the older data if necessary.
For now, we just drop the older tables and recreate them again. Add the following methods to same class. Inserting Note Inserting data requires getting writable instance getReadableDatabase on database.
Below, we are inserting new note in database.
ContentValues is used to define the column name and its data to be stored. Every time the database connection has to be closed once you are done with database access. Reading Notes Reading data requires only read access getReadableDatabase on the database. Updating Note Updating data again requires writable access.
Deleting Note Deleting data also requires writable access. Under utils package, create two classes named RecyclerTouchListener. MyDividerItemDecoration class adds divider line between rows.
Adding Notes UI Now we have the database helper class ready.
First we need an adapter to display the notes in list manner. For this, we need a layout file and Adapter class.You can save your ArrayList in a File and can fetch when needed and its a good practice to not using sharedprefrence for large files,You can use Sqllite database or .
Feb 07, · I am creating an android app, In the app data is read from a JSON file, using a list view the heading is displayed and when a user clicks the heading they are taken to a second screen with the rest of the data. I am having a problem with one aspect, in the JSON file is a part called image which.
I want to write an ArrayList into a text file. The ArrayList is created with the code: ArrayList arr = new ArrayList(); StringTokenizer st .
Jan 27, · hey guys, My app is coming along really nicely but atm i'm stuck on this. I cannot work out how to read and write to a text file.
Everything I have . First of all, let me give you a link: Environment class and getExternalStorageDirectory() method, through this method we gets the root directory of sd-card, because if we write only “/sdcard” as a static value then there may be a chance of problem because there may be having /mnt/sdcard as a root directory in some of android devices.
This tutorial demonstrates how to deal with search view in android using PHP as the server-side scripting language and MySQL as backend.. The user enters a search query into search view/search bar to search for particular information, the query is sent to PHP file and the Android ListView / RecyclerView displays result from PHP file.
Let’s see .