Book Image

Android Studio 4.1 Development Essentials – Java Edition

By : Neil Smyth
Book Image

Android Studio 4.1 Development Essentials – Java Edition

By: Neil Smyth

Overview of this book

For developers, Android 11 has a ton of new capabilities. The goal of this book is to teach the skills necessary to develop Android-based applications using the Java programming language. This book begins with the steps necessary to set up an Android development and testing environment. An overview of Android Studio along with the architecture of Android is covered next, followed by an in-depth look at the design of Android applications and user interfaces using the Android Studio environment. You will also learn about the Android architecture components along with some advanced topics such as touch screen handling, gesture recognition, the recording and playback of audio, app links, dynamic delivery, the AndroidStudio profiler, Gradle build configuration, and submitting apps to the Google Play Developer Console. The concepts of material design, including the use of floating action buttons, Snackbars, tabbed interfaces, card views, navigation drawers, and collapsing toolbars are a highlight of this book. This edition of the book also covers printing, transitions, and cloud-based file storage; the foldable device support is the cherry on the cake. By the end of this course, you will be able to develop Android 11 Apps using Android Studio 4.1, Java, and Android Jetpack. The code files for the book can be found here: https://www.ebookfrenzy.com/retail/androidstudio41/index.php
Table of Contents (88 chapters)
88
Index

15.2 Default Saving of User Interface State

In the previous chapter, the diagnostic output from the StateChange example application showed that an activity goes through a number of state changes when the device on which it is running is rotated sufficiently to trigger an orientation change.

Launch the StateChange application once again, this time entering some text into the EditText field prior to performing the device rotation (on devices or emulators running Android 9 or later it may be necessary to tap the rotation button in the located in the status bar to complete the rotation). Having rotated the device, the following state change sequence should appear in the Logcat window:

onPause

onStop

onSaveInstanceState

onDestroy

onCreate

onStart

onRestoreInstanceState

onResume

Clearly this has resulted in the activity being destroyed and re-created. A review of the user interface of the running application, however, should show that the text entered into the...