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Diffstat (limited to 'actionbarsherlock/src/com/actionbarsherlock/internal/nineoldandroids/animation/FloatEvaluator.java')
-rw-r--r-- | actionbarsherlock/src/com/actionbarsherlock/internal/nineoldandroids/animation/FloatEvaluator.java | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/actionbarsherlock/src/com/actionbarsherlock/internal/nineoldandroids/animation/FloatEvaluator.java b/actionbarsherlock/src/com/actionbarsherlock/internal/nineoldandroids/animation/FloatEvaluator.java new file mode 100644 index 000000000..e41019364 --- /dev/null +++ b/actionbarsherlock/src/com/actionbarsherlock/internal/nineoldandroids/animation/FloatEvaluator.java @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2010 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.actionbarsherlock.internal.nineoldandroids.animation; + +/** + * This evaluator can be used to perform type interpolation between <code>float</code> values. + */ +public class FloatEvaluator implements TypeEvaluator<Number> { + + /** + * This function returns the result of linearly interpolating the start and end values, with + * <code>fraction</code> representing the proportion between the start and end values. The + * calculation is a simple parametric calculation: <code>result = x0 + t * (v1 - v0)</code>, + * where <code>x0</code> is <code>startValue</code>, <code>x1</code> is <code>endValue</code>, + * and <code>t</code> is <code>fraction</code>. + * + * @param fraction The fraction from the starting to the ending values + * @param startValue The start value; should be of type <code>float</code> or + * <code>Float</code> + * @param endValue The end value; should be of type <code>float</code> or <code>Float</code> + * @return A linear interpolation between the start and end values, given the + * <code>fraction</code> parameter. + */ + public Float evaluate(float fraction, Number startValue, Number endValue) { + float startFloat = startValue.floatValue(); + return startFloat + fraction * (endValue.floatValue() - startFloat); + } +}
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