Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Android Studio 4.2 Development Essentials - Java Edition
  • Toc
  • feedback
Android Studio 4.2 Development Essentials - Java Edition

Android Studio 4.2 Development Essentials - Java Edition

By : Neil Smyth
close
Android Studio 4.2 Development Essentials - Java Edition

Android Studio 4.2 Development Essentials - Java Edition

By: Neil Smyth

Overview of this book

Android Studio is an Integrated Development Environment based on the JetBrains IntelliJ IDEA. It provides developers with a unique platform to design and develop Android apps using various developer tools. The new Android Studio 4.2 has an upgraded IntelliJ platform and a variety of new features designed to improve the productivity of Android app developers. Fully updated for Android Studio 4.2, the objective of this book is to help you master the skills necessary to develop Android applications using Java as the programming language. This book begins by outlining the steps necessary to set up an Android development and testing environment and introducing programming in Java, describing data types, flow control, functions, lambdas, and object-oriented programming. It includes an overview of Android Studio, covering areas such as tool windows, the code editor, and the Layout Editor tool. An introduction to Android architecture is followed by an in-depth explanation of the design of Android applications and user interfaces using the Android Studio environment. Early chapters detail Android Architecture components like view models, lifecycle management, Room database access, the Database Inspector, app navigation, live data, and data binding. Advanced topics such as intents are also covered, as are touch screen handling, gesture recognition, and the recording and playback of audio. You will also explore printing, transitions, cloud-based file storage, and foldable device support. Detailed descriptions of the concepts of material design are provided, including the use of floating action buttons, Snackbars, tabbed interfaces, card views, navigation drawers, and collapsing toolbars. Some key features of Android Studio 4.2 and Android discussed in-depth include the Layout Editor, the ConstraintLayout and ConstraintSet classes, MotionLayout Editor, view binding, constraint chains, barriers, and direct reply notifications. Later chapters cover advanced features of Android Studio such as App Links, Dynamic Delivery, the Android Studio Profiler, Gradle build configuration, and submitting apps to the Google Play Developer Console.
Table of Contents (87 chapters)
close
87
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...

bookmark search playlist download font-size

Change the font size

margin-width

Change margin width

day-mode

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Delete Bookmark

Modal Close icon
Are you sure you want to delete it?
Cancel
Yes, Delete