added in version 25.4.0
belongs to Maven artifact com.android.support:support-dynamic-animation:28.0.0-alpha1
Summary: Inherited Constants | Inherited Fields | Ctors | Methods | Inherited Methods | [Expand All]

SpringAnimation

public final class SpringAnimation
extends DynamicAnimation<SpringAnimation>

java.lang.Object
   ↳ android.support.animation.DynamicAnimation<android.support.animation.SpringAnimation>
     ↳ android.support.animation.SpringAnimation

SpringAnimation is an animation that is driven by a SpringForce. The spring force defines the spring's stiffness, damping ratio, as well as the rest position. Once the SpringAnimation is started, on each frame the spring force will update the animation's value and velocity. The animation will continue to run until the spring force reaches equilibrium. If the spring used in the animation is undamped, the animation will never reach equilibrium. Instead, it will oscillate forever.

Developer Guides

To create a simple SpringAnimation that uses the default SpringForce:

 // Create an animation to animate view's X property, set the rest position of the
 // default spring to 0, and start the animation with a starting velocity of 5000 (pixel/s).
 final SpringAnimation anim = new SpringAnimation(view, DynamicAnimation.X, 0)
         .setStartVelocity(5000);
 anim.start();

Alternatively, a SpringAnimation can take a pre-configured SpringForce, and use that to drive the animation. 

 // Create a low stiffness, low bounce spring at position 0.
 SpringForce spring = new SpringForce(0)
         .setDampingRatio(SpringForce.DAMPING_RATIO_LOW_BOUNCY)
         .setStiffness(SpringForce.STIFFNESS_LOW);
 // Create an animation to animate view's scaleY property, and start the animation using
 // the spring above and a starting value of 0.5. Additionally, constrain the range of value for
 // the animation to be non-negative, effectively preventing any spring overshoot.
 final SpringAnimation anim = new SpringAnimation(view, DynamicAnimation.SCALE_Y)
         .setMinValue(0).setSpring(spring).setStartValue(1);
 anim.start();

Summary

Inherited constants

From class android.support.animation.DynamicAnimation

Inherited fields

From class android.support.animation.DynamicAnimation

Public constructors

SpringAnimation(FloatValueHolder floatValueHolder)

This creates a SpringAnimation that animates a FloatValueHolder instance.

SpringAnimation(K object, FloatPropertyCompat<K> property)

This creates a SpringAnimation that animates the property of the given object.

SpringAnimation(K object, FloatPropertyCompat<K> property, float finalPosition)

This creates a SpringAnimation that animates the property of the given object.

Public methods

void animateToFinalPosition(float finalPosition)

Updates the final position of the spring.

boolean canSkipToEnd()

Queries whether the spring can eventually come to the rest position.

SpringForce getSpring()

Returns the spring that the animation uses for animations.

SpringAnimation setSpring(SpringForce force)

Uses the given spring as the force that drives this animation.

void skipToEnd()

Skips to the end of the animation.

void start()

Starts an animation.

Inherited methods

From class android.support.animation.DynamicAnimation
From class java.lang.Object

Public constructors

SpringAnimation

added in version 25.4.0
SpringAnimation (FloatValueHolder floatValueHolder)

This creates a SpringAnimation that animates a FloatValueHolder instance. During the animation, the FloatValueHolder instance will be updated via setValue(float) each frame. The caller can obtain the up-to-date animation value via getValue().

Note: changing the value in the FloatValueHolder via setValue(float) outside of the animation during an animation run will not have any effect on the on-going animation.

Parameters
floatValueHolder FloatValueHolder: the property to be animated

SpringAnimation

added in version 25.4.0
SpringAnimation (K object, 
                FloatPropertyCompat<K> property)

This creates a SpringAnimation that animates the property of the given object. Note, a spring will need to setup through setSpring(SpringForce) before the animation starts.

Parameters
object K: the Object whose property will be animated
property FloatPropertyCompat: the property to be animated

SpringAnimation

added in version 25.4.0
SpringAnimation (K object, 
                FloatPropertyCompat<K> property, 
                float finalPosition)

This creates a SpringAnimation that animates the property of the given object. A Spring will be created with the given final position and default stiffness and damping ratio. This spring can be accessed and reconfigured through setSpring(SpringForce).

Parameters
object K: the Object whose property will be animated
property FloatPropertyCompat: the property to be animated
finalPosition float: the final position of the spring to be created.

Public methods

animateToFinalPosition

added in version 25.4.0
void animateToFinalPosition (float finalPosition)

Updates the final position of the spring.

When the animation is running, calling this method would assume the position change of the spring as a continuous movement since last frame, which yields more accurate results than changing the spring position directly through setFinalPosition(float).

If the animation hasn't started, calling this method will change the spring position, and immediately start the animation.

Parameters
finalPosition float: rest position of the spring

canSkipToEnd

added in version 25.4.0
boolean canSkipToEnd ()

Queries whether the spring can eventually come to the rest position.

Returns
boolean true if the spring is damped, otherwise false

getSpring

added in version 25.4.0
SpringForce getSpring ()

Returns the spring that the animation uses for animations.

Returns
SpringForce the spring that the animation uses for animations

setSpring

added in version 25.4.0
SpringAnimation setSpring (SpringForce force)

Uses the given spring as the force that drives this animation. If this spring force has its parameters re-configured during the animation, the new configuration will be reflected in the animation immediately.

Parameters
force SpringForce: a pre-defined spring force that drives the animation
Returns
SpringAnimation the animation that the spring force is set on

skipToEnd

added in version 25.4.0
void skipToEnd ()

Skips to the end of the animation. If the spring is undamped, an IllegalStateException will be thrown, as the animation would never reach to an end. It is recommended to check canSkipToEnd() before calling this method. This method should only be called on main thread. If animation is not running, no-op.

Throws
IllegalStateException if the spring is undamped (i.e. damping ratio = 0)
AndroidRuntimeException if this method is not called on the main thread

start

added in version 25.4.0
void start ()

Starts an animation. If the animation has already been started, no op. Note that calling start() will not immediately set the property value to start value of the animation. The property values will be changed at each animation pulse, which happens before the draw pass. As a result, the changes will be reflected in the next frame, the same as if the values were set immediately. This method should only be called on main thread.