Book Image

Android Studio 3.5 Development Essentials - Java Edition

By : Neil Smyth
Book Image

Android Studio 3.5 Development Essentials - Java Edition

By: Neil Smyth

Overview of this book

Android applications have become an important part of our daily lives and lots of effort goes into developing an Android application. This book will help you to build you own Android applications using Java. Android Studio 3.5 Development Essentials – Java Edition first teaches you to install Android development and test environment on different operating systems. Next, you will create an Android app and a virtual device in Android Studio, and install an Android application on emulator. You will test apps on physical Android devices, then study Android Studio code editor and constraint layout, Android architecture, the anatomy of an Android app, and Android activity state changes. The book then covers advanced topics such as views and widgets implementation, multi-window support integration, and biometric authentication, and finally, you will learn to upload your app to Google Play console and handle the build process with Gradle. By the end of this book, you will have gained enough knowledge to develop powerful Android applications using Java.
Table of Contents (86 chapters)
86
Index

67.8 Gaining Persistent Access to a File

When an application gains access to a file via the Storage Access Framework, the access will remain valid until the Android device on which the application is running is restarted. Persistent access to a specific file can be obtained by “taking” the necessary permissions for the Uri. The following code, for example, persists read and write permissions for the file referenced by the fileUri Uri instance:

final int takeFlags = intent.getFlags()

            & (Intent.FLAG_GRANT_READ_URI_PERMISSION

            | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);

 

getContentResolver().takePersistableUriPermission(fileUri, takeFlags);

Once the permissions for the file have been taken by the application, and assuming the Uri has been saved by the application, the user should be able to continue accessing...