Files
Flexera-Launcher/src/com/android/launcher3/anim/FlingSpringAnim.java
T
Jon Miranda 2da1da3076 Initial app open/close polish using tuned values.
* Rect and radius now match the app window size.

Bug: 124510042
Bug: 122843905
Change-Id: Ibc85bfe1d75d01cefe00b6bf32557e04a0ee4716
2019-05-10 10:11:35 -07:00

86 lines
3.3 KiB
Java

/*
* Copyright (C) 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.launcher3.anim;
import androidx.dynamicanimation.animation.DynamicAnimation.OnAnimationEndListener;
import androidx.dynamicanimation.animation.FlingAnimation;
import androidx.dynamicanimation.animation.FloatPropertyCompat;
import androidx.dynamicanimation.animation.SpringAnimation;
import androidx.dynamicanimation.animation.SpringForce;
/**
* Given a property to animate and a target value and starting velocity, first apply friction to
* the fling until we pass the target, then apply a spring force to pull towards the target.
*/
public class FlingSpringAnim {
private static final float FLING_FRICTION = 1.5f;
// Have the spring pull towards the target if we've slowed down too much before reaching it.
private static final float FLING_END_THRESHOLD_PX = 50f;
private static final float SPRING_STIFFNESS = 200;
private static final float SPRING_DAMPING = 0.85f;
private final FlingAnimation mFlingAnim;
private SpringAnimation mSpringAnim;
private float mTargetPosition;
public <K> FlingSpringAnim(K object, FloatPropertyCompat<K> property, float startPosition,
float targetPosition, float startVelocity, OnAnimationEndListener onEndListener) {
mFlingAnim = new FlingAnimation(object, property)
.setFriction(FLING_FRICTION)
.setMinimumVisibleChange(FLING_END_THRESHOLD_PX)
.setStartVelocity(startVelocity)
.setMinValue(Math.min(startPosition, targetPosition))
.setMaxValue(Math.max(startPosition, targetPosition));
mTargetPosition = targetPosition;
mFlingAnim.addEndListener(((animation, canceled, value, velocity) -> {
mSpringAnim = new SpringAnimation(object, property)
.setStartVelocity(velocity)
.setSpring(new SpringForce(mTargetPosition)
.setStiffness(SPRING_STIFFNESS)
.setDampingRatio(SPRING_DAMPING));
mSpringAnim.addEndListener(onEndListener);
mSpringAnim.start();
}));
}
public float getTargetPosition() {
return mTargetPosition;
}
public void updatePosition(float startPosition, float targetPosition) {
mFlingAnim.setMinValue(Math.min(startPosition, targetPosition))
.setMaxValue(Math.max(startPosition, targetPosition));
mTargetPosition = targetPosition;
if (mSpringAnim != null) {
mSpringAnim.animateToFinalPosition(mTargetPosition);
}
}
public void start() {
mFlingAnim.start();
}
public void end() {
mFlingAnim.cancel();
if (mSpringAnim.canSkipToEnd()) {
mSpringAnim.skipToEnd();
}
}
}