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

35.6 Assigning the ViewModel Instance to the Data Binding Variable

At this point, the data binding knows that it will be binding to an instance of a class of type MainViewModel but has not yet been connected to an actual MainViewModel object. This requires the additional step of assigning the MainViewModel instance used within the app to the viewModel variable declared in the layout file. Since the reference to the ViewModel is obtained in the onActivityCreated() method, it makes sense to make the assignment there:

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.

import static com.ebookfrenzy.viewmodeldemo.BR.myViewModel;

.

.

@Override

public void onActivityCreated(@Nullable Bundle savedInstanceState) {

    super.onActivityCreated(savedInstanceState);

 

    mViewModel = ViewModelProviders.of(this).get(MainViewModel.class);

    binding.setVariable(myViewModel, mViewModel);

}

With these changes made, the next step is to begin...