/*
 * Copyright (C) 2007 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 android.view.animation;

import android.content.Context;
import android.content.res.Resources;
import android.content.res.Resources.Theme;
import android.content.res.TypedArray;
import android.util.AttributeSet;

import com.android.internal.R;
import com.android.internal.view.animation.HasNativeInterpolator;
import com.android.internal.view.animation.NativeInterpolatorFactory;
import com.android.internal.view.animation.NativeInterpolatorFactoryHelper;

An interpolator where the rate of change starts out quickly and and then decelerates.
/** * An interpolator where the rate of change starts out quickly and * and then decelerates. * */
@HasNativeInterpolator public class DecelerateInterpolator extends BaseInterpolator implements NativeInterpolatorFactory { public DecelerateInterpolator() { }
Constructor
Params:
  • factor – Degree to which the animation should be eased. Setting factor to 1.0f produces an upside-down y=x^2 parabola. Increasing factor above 1.0f exaggerates the ease-out effect (i.e., it starts even faster and ends evens slower).
/** * Constructor * * @param factor Degree to which the animation should be eased. Setting factor to 1.0f produces * an upside-down y=x^2 parabola. Increasing factor above 1.0f exaggerates the * ease-out effect (i.e., it starts even faster and ends evens slower). */
public DecelerateInterpolator(float factor) { mFactor = factor; } public DecelerateInterpolator(Context context, AttributeSet attrs) { this(context.getResources(), context.getTheme(), attrs); }
@hide
/** @hide */
public DecelerateInterpolator(Resources res, Theme theme, AttributeSet attrs) { TypedArray a; if (theme != null) { a = theme.obtainStyledAttributes(attrs, R.styleable.DecelerateInterpolator, 0, 0); } else { a = res.obtainAttributes(attrs, R.styleable.DecelerateInterpolator); } mFactor = a.getFloat(R.styleable.DecelerateInterpolator_factor, 1.0f); setChangingConfiguration(a.getChangingConfigurations()); a.recycle(); } public float getInterpolation(float input) { float result; if (mFactor == 1.0f) { result = (float)(1.0f - (1.0f - input) * (1.0f - input)); } else { result = (float)(1.0f - Math.pow((1.0f - input), 2 * mFactor)); } return result; } private float mFactor = 1.0f;
@hide
/** @hide */
@Override public long createNativeInterpolator() { return NativeInterpolatorFactoryHelper.createDecelerateInterpolator(mFactor); } }