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You're reading from  Asynchronous Android Programming - Second Edition

Product typeBook
Published inJul 2016
Reading LevelBeginner
PublisherPackt
ISBN-139781785883248
Edition2nd Edition
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Steve Liles
Steve Liles
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Steve Liles

Steve Liles is a self-confessed geek and has been an Android fan since the launch day of the G1. When he isn't at work building publishing systems and apps for newspapers and magazines, you'll find him tinkering with his own apps, building 3D printers, or playing RTS games. He is currently working with a start-up to build an advertising system that links the print and digital worlds using computer vision on Android and iOS devices.
Read more about Steve Liles

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Understanding Looper


Before we can understand Looper, we need to understand where it gets its name from.

Note

A loop is a group of instructions that are repeated continually until a termination condition is met.

Following this definition, Android's Looper executes on a thread that has a MessageQueue, executes a continuous loop waiting for work, and blocks when there is no work pending. When work is submitted to its queue, it dispatches it to the target Handler defined explicitly on the Message object.

Note

A message is a notification object containing a description and arbitrary data object that can be sent to a Handler.

The Looper on Android is an implementation of a common UI programming concept known as an event loop. Later, at the end of this processing sequence, the Handler will process the Message and execute your domain logic in order to solve an application user problem.

The Looper sequence on Android follows these steps:

  1. Wait until a Message is retrieved from its MessageQueue

  2. If logging...

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Asynchronous Android Programming - Second Edition
Published in: Jul 2016Publisher: PacktISBN-13: 9781785883248

Author (1)

author image
Steve Liles

Steve Liles is a self-confessed geek and has been an Android fan since the launch day of the G1. When he isn't at work building publishing systems and apps for newspapers and magazines, you'll find him tinkering with his own apps, building 3D printers, or playing RTS games. He is currently working with a start-up to build an advertising system that links the print and digital worlds using computer vision on Android and iOS devices.
Read more about Steve Liles