xref: /frameworks/support/compat/java/android/support/v4/view/ViewPropertyAnimatorCompat.java

/*
 * Copyright (C) 2014 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.support.v4.view;

import android.view.View;
import android.view.animation.Interpolator;

import java.lang.ref.WeakReference;

public class ViewPropertyAnimatorCompat {
    private static final String TAG = "ViewAnimatorCompat";
    private WeakReference<View> mView;

    ViewPropertyAnimatorCompat(View view) {
        mView = new WeakReference<View>(view);
    }

    interface ViewPropertyAnimatorCompatImpl {
        public void setDuration(View view, long value);
        public long getDuration(View view);
        public void setInterpolator(View view, Interpolator value);
        public Interpolator getInterpolator(View view);
        public void setStartDelay(View view, long value);
        public long getStartDelay(View view);
        public void alpha(View view, float value);
        public void alphaBy(View view, float value);
        public void rotation(View view, float value);
        public void rotationBy(View view, float value);
        public void rotationX(View view, float value);
        public void rotationXBy(View view, float value);
        public void rotationY(View view, float value);
        public void rotationYBy(View view, float value);
        public void scaleX(View view, float value);
        public void scaleXBy(View view, float value);
        public void scaleY(View view, float value);
        public void scaleYBy(View view, float value);
        public void cancel(View view);
        public void x(View view, float value);
        public void xBy(View view, float value);
        public void y(View view, float value);
        public void yBy(View view, float value);
        public void translationX(View view, float value);
        public void translationXBy(View view, float value);
        public void translationY(View view, float value);
        public void translationYBy(View view, float value);
        public void start(View view);
        public void withLayer(View view);
        public void withStartAction(View view, Runnable runnable);
        public void withEndAction(View view, Runnable runnable);
        public void setListener(View view, ViewPropertyAnimatorListener listener);
        public void setUpdateListener(View view, ViewPropertyAnimatorUpdateListener listener);
    };

    static class BaseViewPropertyAnimatorCompatImpl implements ViewPropertyAnimatorCompatImpl {
        private ViewPropertyAnimatorListener mListener;

        @Override
        public void setDuration(View view, long value) {
            // noop on versions prior to ICS
        }

        @Override
        public void alpha(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void translationX(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void translationY(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void withEndAction(View view, Runnable runnable) {
            // Other VPA calls are noops pre-ICS; just run the runnable immediately
            runnable.run();
        }

        @Override
        public long getDuration(View view) {
            return 0;
        }

        @Override
        public void setInterpolator(View view, Interpolator value) {
            // noop on versions prior to ICS
        }

        @Override
        public Interpolator getInterpolator(View view) {
            return null;
        }

        @Override
        public void setStartDelay(View view, long value) {
            // noop on versions prior to ICS
        }

        @Override
        public long getStartDelay(View view) {
            return 0;
        }

        @Override
        public void alphaBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void rotation(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void rotationBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void rotationX(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void rotationXBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void rotationY(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void rotationYBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void scaleX(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void scaleXBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void scaleY(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void scaleYBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void cancel(View view) {
            // noop on versions prior to ICS
        }

        @Override
        public void x(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void xBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void y(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void yBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void translationXBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void translationYBy(View view, float value) {
            // noop on versions prior to ICS
        }

        @Override
        public void start(View view) {
            if (mListener != null) {
                // If a listener has been set, start and then end it immediately
                mListener.onAnimationStart(view);
                mListener.onAnimationEnd(view);
            }
        }

        @Override
        public void withLayer(View view) {
            // noop on versions prior to ICS
        }

        @Override
        public void withStartAction(View view, Runnable runnable) {
            // Other VPA calls are noops pre-ICS; just run the runnable immediately
            runnable.run();
        }

        @Override
        public void setListener(View view, ViewPropertyAnimatorListener listener) {
            mListener = listener;
        }

        @Override
        public void setUpdateListener(View view, ViewPropertyAnimatorUpdateListener listener) {
            // noop
        }
    }

    static class ICSViewPropertyAnimatorCompatImpl extends BaseViewPropertyAnimatorCompatImpl {

        @Override
        public void setDuration(View view, long value) {
            ViewPropertyAnimatorCompatICS.setDuration(view, value);
        }

        @Override
        public void alpha(View view, float value) {
            ViewPropertyAnimatorCompatICS.alpha(view, value);
        }

        @Override
        public void translationX(View view, float value) {
            ViewPropertyAnimatorCompatICS.translationX(view, value);
        }

        @Override
        public void translationY(View view, float value) {
            ViewPropertyAnimatorCompatICS.translationY(view, value);
        }

        @Override
        public long getDuration(View view) {
            return ViewPropertyAnimatorCompatICS.getDuration(view);
        }

        @Override
        public void setInterpolator(View view, Interpolator value) {
            ViewPropertyAnimatorCompatICS.setInterpolator(view, value);
        }

        @Override
        public void setStartDelay(View view, long value) {
            ViewPropertyAnimatorCompatICS.setStartDelay(view, value);
        }

        @Override
        public long getStartDelay(View view) {
            return ViewPropertyAnimatorCompatICS.getStartDelay(view);
        }

        @Override
        public void alphaBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.alphaBy(view, value);
        }

        @Override
        public void rotation(View view, float value) {
            ViewPropertyAnimatorCompatICS.rotation(view, value);
        }

        @Override
        public void rotationBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.rotationBy(view, value);
        }

        @Override
        public void rotationX(View view, float value) {
            ViewPropertyAnimatorCompatICS.rotationX(view, value);
        }

        @Override
        public void rotationXBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.rotationXBy(view, value);
        }

        @Override
        public void rotationY(View view, float value) {
            ViewPropertyAnimatorCompatICS.rotationY(view, value);
        }

        @Override
        public void rotationYBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.rotationYBy(view, value);
        }

        @Override
        public void scaleX(View view, float value) {
            ViewPropertyAnimatorCompatICS.scaleX(view, value);
        }

        @Override
        public void scaleXBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.scaleXBy(view, value);
        }

        @Override
        public void scaleY(View view, float value) {
            ViewPropertyAnimatorCompatICS.scaleY(view, value);
        }

        @Override
        public void scaleYBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.scaleYBy(view, value);
        }

        @Override
        public void cancel(View view) {
            ViewPropertyAnimatorCompatICS.cancel(view);
        }

        @Override
        public void x(View view, float value) {
            ViewPropertyAnimatorCompatICS.x(view, value);
        }

        @Override
        public void xBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.xBy(view, value);
        }

        @Override
        public void y(View view, float value) {
            ViewPropertyAnimatorCompatICS.y(view, value);
        }

        @Override
        public void yBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.yBy(view, value);
        }

        @Override
        public void translationXBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.translationXBy(view, value);
        }

        @Override
        public void translationYBy(View view, float value) {
            ViewPropertyAnimatorCompatICS.translationYBy(view, value);
        }

        @Override
        public void start(View view) {
            ViewPropertyAnimatorCompatICS.start(view);
        }

        @Override
        public void setListener(View view, ViewPropertyAnimatorListener listener) {
            ViewPropertyAnimatorCompatICS.setListener(view, listener);
        }

        @Override
        public void withEndAction(View view, final Runnable runnable) {
            setListener(view, new ViewPropertyAnimatorListener() {
                @Override
                public void onAnimationStart(View view) {
                }

                @Override
                public void onAnimationEnd(View view) {
                    runnable.run();
                    setListener(view, null);
                }

                @Override
                public void onAnimationCancel(View view) {
                }
            });
        }

        @Override
        public void withStartAction(View view, final Runnable runnable) {
            setListener(view, new ViewPropertyAnimatorListener() {
                @Override
                public void onAnimationStart(View view) {
                    runnable.run();
                    setListener(view, null);
                }

                @Override
                public void onAnimationEnd(View view) {
                }

                @Override
                public void onAnimationCancel(View view) {
                }
            });
        }

        @Override
        public void withLayer(View view) {
            final int currentLayerType = ViewCompat.getLayerType(view);
            setListener(view, new ViewPropertyAnimatorListener() {
                @Override
                public void onAnimationStart(View view) {
                    ViewCompat.setLayerType(view, ViewCompat.LAYER_TYPE_HARDWARE, null);
                }
                @Override
                public void onAnimationEnd(View view) {
                    ViewCompat.setLayerType(view, currentLayerType, null);
                    setListener(view, null);
                }

                @Override
                public void onAnimationCancel(View view) {
                }
            });
        }
    }

    static class JBViewPropertyAnimatorCompatImpl extends ICSViewPropertyAnimatorCompatImpl {

        @Override
        public void withStartAction(View view, Runnable runnable) {
            ViewPropertyAnimatorCompatJB.withStartAction(view, runnable);
        }

        @Override
        public void withEndAction(View view, Runnable runnable) {
            ViewPropertyAnimatorCompatJB.withEndAction(view, runnable);
        }

        @Override
        public void withLayer(View view) {
            ViewPropertyAnimatorCompatJB.withLayer(view);
        }
    }

    static class JBMr2ViewPropertyAnimatorCompatImpl extends JBViewPropertyAnimatorCompatImpl {

        @Override
        public Interpolator getInterpolator(View view) {
            return (Interpolator) ViewPropertyAnimatorCompatJellybeanMr2.getInterpolator(view);
        }
    }

    static class KitKatViewPropertyAnimatorCompatImpl extends JBMr2ViewPropertyAnimatorCompatImpl {
        @Override
        public void setUpdateListener(View view, ViewPropertyAnimatorUpdateListener listener) {
            ViewPropertyAnimatorCompatKK.setUpdateListener(view, listener);
        }
    }

    static final ViewPropertyAnimatorCompatImpl IMPL;
    static {
        final int version = android.os.Build.VERSION.SDK_INT;
        if (version >= 19) {
            IMPL = new KitKatViewPropertyAnimatorCompatImpl();
        } else if (version >= 18) {
            IMPL = new JBMr2ViewPropertyAnimatorCompatImpl();
        } else if (version >= 16) {
            IMPL = new JBViewPropertyAnimatorCompatImpl();
        } else if (version >= 14) {
            IMPL = new ICSViewPropertyAnimatorCompatImpl();
        } else {
            IMPL = new BaseViewPropertyAnimatorCompatImpl();
        }
    }

    /**
     * Sets the duration for the underlying animator that animates the requested properties.
     * By default, the animator uses the default value for ValueAnimator. Calling this method
     * will cause the declared value to be used instead.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The length of ensuing property animations, in milliseconds. The value
     * cannot be negative.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat setDuration(long value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.setDuration(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>alpha</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat alpha(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.alpha(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>alpha</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat alphaBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.alphaBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>translationX</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat translationX(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.translationX(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>translationY</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat translationY(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.translationY(view, value);
        }
        return this;
    }

    /**
     * Specifies an action to take place when the next animation ends. The action is only
     * run if the animation ends normally; if the ViewPropertyAnimator is canceled during
     * that animation, the runnable will not run.
     * This method, along with {@link #withStartAction(Runnable)}, is intended to help facilitate
     * choreographing ViewPropertyAnimator animations with other animations or actions
     * in the application.
     *
     * <p>For example, the following code animates a view to x=200 and then back to 0:</p>
     * <pre>
     *     Runnable endAction = new Runnable() {
     *         public void run() {
     *             view.animate().x(0);
     *         }
     *     };
     *     view.animate().x(200).withEndAction(endAction);
     * </pre>
     *
     * <p>Prior to API 14, this method will run the action immediately.</p>
     *
     * <p>For API 14 and 15, this method will run by setting
     * a listener on the ViewPropertyAnimatorCompat object and running the action
     * in that listener's {@link ViewPropertyAnimatorListener#onAnimationEnd(View)} method.</p>
     *
     * @param runnable The action to run when the next animation ends.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat withEndAction(Runnable runnable) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.withEndAction(view, runnable);
        }
        return this;
    }

    /**
     * Returns the current duration of property animations. If the duration was set on this
     * object, that value is returned. Otherwise, the default value of the underlying Animator
     * is returned.
     *
     * <p>Prior to API 14, this method will return 0.</p>
     *
     * @see #setDuration(long)
     * @return The duration of animations, in milliseconds.
     */
    public long getDuration() {
        View view;
        if ((view = mView.get()) != null) {
            return IMPL.getDuration(view);
        } else {
            return 0;
        }
    }

    /**
     * Sets the interpolator for the underlying animator that animates the requested properties.
     * By default, the animator uses the default interpolator for ValueAnimator. Calling this method
     * will cause the declared object to be used instead.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The TimeInterpolator to be used for ensuing property animations.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat setInterpolator(Interpolator value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.setInterpolator(view, value);
        }
        return this;
    }

    /**
     * Returns the timing interpolator that this animation uses.
     *
     * <p>Prior to API 14, this method will return null.</p>
     *
     * @return The timing interpolator for this animation.
     */
    public Interpolator getInterpolator() {
        View view;
        if ((view = mView.get()) != null) {
            return IMPL.getInterpolator(view);
        }
        else return null;
    }

    /**
     * Sets the startDelay for the underlying animator that animates the requested properties.
     * By default, the animator uses the default value for ValueAnimator. Calling this method
     * will cause the declared value to be used instead.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The delay of ensuing property animations, in milliseconds. The value
     * cannot be negative.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat setStartDelay(long value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.setStartDelay(view, value);
        }
        return this;
    }

    /**
     * Returns the current startDelay of property animations. If the startDelay was set on this
     * object, that value is returned. Otherwise, the default value of the underlying Animator
     * is returned.
     *
     * <p>Prior to API 14, this method will return 0.</p>
     *
     * @see #setStartDelay(long)
     * @return The startDelay of animations, in milliseconds.
     */
    public long getStartDelay() {
        View view;
        if ((view = mView.get()) != null) {
            return IMPL.getStartDelay(view);
        } else {
            return 0;
        }
    }

    /**
     * This method will cause the View's <code>rotation</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat rotation(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.rotation(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>rotation</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat rotationBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.rotationBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>rotationX</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat rotationX(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.rotationX(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>rotationX</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat rotationXBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.rotationXBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>rotationY</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat rotationY(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.rotationY(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>rotationY</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat rotationYBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.rotationYBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>scaleX</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat scaleX(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.scaleX(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>scaleX</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat scaleXBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.scaleXBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>scaleY</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat scaleY(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.scaleY(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>scaleY</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat scaleYBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.scaleYBy(view, value);
        }
        return this;
    }

    /**
     * Cancels all property animations that are currently running or pending.
     */
    public void cancel() {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.cancel(view);
        }
    }

    /**
     * This method will cause the View's <code>x</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat x(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.x(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>x</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat xBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.xBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>y</code> property to be animated to the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The value to be animated to.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat y(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.y(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>y</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat yBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.yBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>translationX</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat translationXBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.translationXBy(view, value);
        }
        return this;
    }

    /**
     * This method will cause the View's <code>translationY</code> property to be animated by the
     * specified value. Animations already running on the property will be canceled.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param value The amount to be animated by, as an offset from the current value.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat translationYBy(float value) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.translationYBy(view, value);
        }
        return this;
    }

    /**
     * Starts the currently pending property animations immediately. Calling <code>start()</code>
     * is optional because all animations start automatically at the next opportunity. However,
     * if the animations are needed to start immediately and synchronously (not at the time when
     * the next event is processed by the hierarchy, which is when the animations would begin
     * otherwise), then this method can be used.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     */
    public void start() {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.start(view);
        }
    }

    /**
     * The View associated with this ViewPropertyAnimator will have its
     * {@link ViewCompat#setLayerType(View, int, android.graphics.Paint) layer type} set to
     * {@link ViewCompat#LAYER_TYPE_HARDWARE} for the duration of the next animation.
     * As stated in the documentation for {@link ViewCompat#LAYER_TYPE_HARDWARE},
     * the actual type of layer used internally depends on the runtime situation of the
     * view. If the activity and this view are hardware-accelerated, then the layer will be
     * accelerated as well. If the activity or the view is not accelerated, then the layer will
     * effectively be the same as {@link ViewCompat#LAYER_TYPE_SOFTWARE}.
     *
     * <p>This state is not persistent, either on the View or on this ViewPropertyAnimator: the
     * layer type of the View will be restored when the animation ends to what it was when this
     * method was called, and this setting on ViewPropertyAnimator is only valid for the next
     * animation. Note that calling this method and then independently setting the layer type of
     * the View (by a direct call to
     * {@link ViewCompat#setLayerType(View, int, android.graphics.Paint)}) will result in some
     * inconsistency, including having the layer type restored to its pre-withLayer()
     * value when the animation ends.</p>
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * <p>For API 14 and 15, this method will run by setting
     * a listener on the ViewPropertyAnimatorCompat object, setting a hardware layer in
     * the listener's {@link ViewPropertyAnimatorListener#onAnimationStart(View)} method,
     * and then restoring the orignal layer type in the listener's
     * {@link ViewPropertyAnimatorListener#onAnimationEnd(View)} method.</p>
     *
     * @see View#setLayerType(int, android.graphics.Paint)
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat withLayer() {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.withLayer(view);
        }
        return this;
    }

    /**
     * Specifies an action to take place when the next animation runs. If there is a
     * {@link #setStartDelay(long) startDelay} set on this ViewPropertyAnimator, then the
     * action will run after that startDelay expires, when the actual animation begins.
     * This method, along with {@link #withEndAction(Runnable)}, is intended to help facilitate
     * choreographing ViewPropertyAnimator animations with other animations or actions
     * in the application.
     *
     * <p>Prior to API 14, this method will run the action immediately.</p>
     *
     * <p>For API 14 and 15, this method will run by setting
     * a listener on the ViewPropertyAnimatorCompat object and running the action
     * in that listener's {@link ViewPropertyAnimatorListener#onAnimationStart(View)} method.</p>
     *
     * @param runnable The action to run when the next animation starts.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat withStartAction(Runnable runnable) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.withStartAction(view, runnable);
        }
        return this;
    }

    /**
     * Sets a listener for events in the underlying Animators that run the property
     * animations.
     *
     * <p>Prior to API 14, this method will do nothing.</p>
     *
     * @param listener The listener to be called with AnimatorListener events. A value of
     * <code>null</code> removes any existing listener.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat setListener(ViewPropertyAnimatorListener listener) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.setListener(view, listener);
        }
        return this;
    }

    /**
     * Sets a listener for update events in the underlying Animator that runs
     * the property animations.
     *
     * <p>Prior to API 19, this method will do nothing.</p>
     *
     * @param listener The listener to be called with update events. A value of
     * <code>null</code> removes any existing listener.
     * @return This object, allowing calls to methods in this class to be chained.
     */
    public ViewPropertyAnimatorCompat setUpdateListener(
            ViewPropertyAnimatorUpdateListener listener) {
        View view;
        if ((view = mView.get()) != null) {
            IMPL.setUpdateListener(view, listener);
        }
        return this;
    }
}