Android SQL Database Adapter

First of all, to manage data in a private database in your Android phone/tablet, we will use SQLite as it is embedded into every Android device.
We need to import android.database.sqlite for access to those classes of SQLite to manage your database in your apps.

START_STICKY, START_NOT_STICKY, START_REDELIVER_INTENT

All these are to tell android system what to do if the service is got 'killed'

As you know, there are lots of services keep running in the background and they will consume some memory. For simplicity, under 2 situation will the services being terminated:
- When our device memory goes down to a critical level it will automatically start terminating services to release memory.
- Users manually stopped the services (Oh! I find you the invisible memory killer!! Go to die!!! .\ /. )

BigDecimal.divide ArithmeticException

Sometimes, when we are using the divide function of BigDecimal like this:

BigDecimal d1 = new BigDecimal(1);
BigDecimal d2 = new BigDecimal(3);
BigDecimal result= d1.divide(d2); // 1/3 = 0.33333333....

The following exception will be thrown:
Exception in thread "main" java.lang.ArithmeticException: Non-terminating decimal expansion; no exact representable decimal result.

This is caused as the division results into a recurring decimal which cannot be represented by BigDecimal.
To solve this, simply add rounding parameters into the function divide(divisor, scale, roundingMode):

BigDecimal d1 = new BigDecimal(1);
BigDecimal d2 = new BigDecimal(3);
BigDecimal result= d1.divide(d2, 2, BigDecimal.ROUND_HALF_UP); // 1/3 = 0.33

Android Service

For simplicity,
For those running in foreground, they are called 'Activity' (those applications we can see and use in our mobile)
For those running in background, they are called 'Service' (those we cannot see while running in background and keep consuming your mobile's RAM. Haha they are one of the evilest guys that make your mobile so slow)

Notification with Big View

A notification's big view appears only when the notification is expanded, which happens when the notification is at the top of the notification drawer, or when the user expands the notification with a gesture. Expanded notifications are available starting with Android 4.1.

Spinner with item text aligned to center

In Android, text in Spinner is defaulted to align to left. To change the alignment, we need to create our own layout for the Spinner

SAP - Availability Check

The availability of components in an order can be checked automatically during order creation and/or order release
The availability of components in a plan order can be checked manually by MDVP