How a layout can be included in Android?

You can declare a layout in two ways: Declare UI elements in XML. Android provides a straightforward XML vocabulary that corresponds to the View classes and subclasses, such as those for widgets and layouts. You can also use Android Studio’s Layout Editor to build your XML layout using a drag-and-drop interface.

What is the use of include in Android?

To efficiently re-use complete layouts, you can use the <include/> and <merge/> tags to embed another layout inside the current layout. Reusing layouts is particularly powerful as it allows you to create reusable complex layouts. For example, a yes/no button panel, or custom progress bar with description text.