Dynamic Animation Example

Dynamic-animation is a new module introduced in revision 25.3.0 of the Android Support Library. It provides a small set of classes for making realistic physics-based view animations.

example

Setup

To get started, add the following dependency to your module’s build.gradle:

dependencies {
    compile 'com.android.support:support-dynamic-animation:25.3.0'
}
Gradle

support-dynamic-animation:25.3.0 new physics-based animation library that provides a set of APIs for building animations that dynamically react to user input

Making a SpringAnimation

Well, it won’t really be generic in a programming sense, but let’s start with how every SpringAnimation is made.

  1. Create a SpringAnimation object for your View with a specified ViewProperty
  2. Create a SpringForce object and set your desired parameters (which are described above).
  3. Apply the created SpringForce to your SpringAnimation.
  4. Start the animation.
 private void startSpringAnimation(View view){
        // create an animation for your view and set the property you want to animate
        SpringAnimation animation = new SpringAnimation(view, SpringAnimation.X);
        // create a spring with desired parameters
        SpringForce spring = new SpringForce();
        // can also be passed directly in the constructor
        spring.setFinalPosition(100f);
        // optional, default is STIFFNESS_MEDIUM
        spring.setStiffness(SpringForce.STIFFNESS_LOW); 
        // optional, default is DAMPING_RATIO_MEDIUM_BOUNCY
        spring.setDampingRatio(SpringForce.DAMPING_RATIO_HIGH_BOUNCY);
        // set your animation's spring
        animation.setSpring(spring);
        // animate!
        animation.start();
    }
Java

Position

Let’s say we have an arbitrary view positioned in the center of the screen
We want to achieve the following behavior:

  1. Drag the view.
  2. Move it around.
  3. Release it.
  4. The view springs back to its original position.

Rotation

There’s a rotating view on our screen which behaves like this:

  1. Grab the view.
  2. Spin it.
  3. Release it.
  4. The view spins back to its original position, again with a bounce.

Scale

As usual, there’s a view on our screen (it could be a photo) which has the following behavior:

  1. Grab it with 2 fingers.
  2. Do a typical pinching gesture to zoom in or out.
  3. Release it.
  4. The view scales back to its original size.

Feel free to fork, contribute and poke at the code.

GitHub