Pinch-to-zoom with multi-touch gestures In Android

In this article, we will demonstrate multi-touch with the common pinch-to-zoom gesture using the SimpleOnScaleGestureListener class. The aim is to give you a head start if you intend to add pinch-to-zoom feature in your project.

The following screen-shot shows the icon zoomed in and out using the application created :

when zoomed in

when zoomed out

Okay, Let’s get started!.

1. Create a new project in Android Studio and call it: Pinch2Zoom or whatever you like. Use the default Phone & Tablet options and select Empty Activity when prompted for the Activity Type.
2. We’ll use an ImageView with the application icon to provide a visual indication of the pinch-to-zoom. Open activity_main.xml and Replace the existing TextView with the following ImageView :

<ImageView
android:id="@+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"