/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
package com.facebook.react.animation;
import android.view.View;
/**
* Base class for {@link AnimationPropertyUpdater} subclasses that updates a single float property
* value. It helps to handle convertion from animation progress to the actual value as well as the
* quite common case when no starting value is provided.
*/
public abstract class AbstractSingleFloatProperyUpdater implements AnimationPropertyUpdater {
private float mFromValue, mToValue;
private boolean mFromSource;
protected AbstractSingleFloatProperyUpdater(float toValue) {
mToValue = toValue;
mFromSource = true;
}
protected AbstractSingleFloatProperyUpdater(float fromValue, float toValue) {
this(toValue);
mFromValue = fromValue;
mFromSource = false;
}
protected abstract float getProperty(View view);
protected abstract void setProperty(View view, float propertyValue);
@Override
public final void prepare(View view) {
if (mFromSource) {
mFromValue = getProperty(view);
}
}
@Override
public final void onUpdate(View view, float progress) {
setProperty(view, mFromValue + (mToValue - mFromValue) * progress);
}
@Override
public void onFinish(View view) {
setProperty(view, mToValue);
}
}