为Android的早期版本（Lollipop之前）创建圆形揭示效果

Question

是否有可能为Lollipop之前的设备获取这个新的动画器？

我是一名新手，正在尝试从官方文档中获取java文件，但是我真的很迷茫，不知道该如何找到它等等。

- JavierSegoviaCordoba

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请使用CircularRevealCompat和com.google.android.material.circularreveal.CircularRevealFrameLayout。 - Shubham AgaRwal

Answer 1

我给您找到一个库。 Circular reveal 可与2.3设备兼容。希望对您有所帮助！

- Alejandro Martínez Martínez

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这个能在Activity转换中使用吗？ - JayVDiyk

但它需要最低SDK版本为15。 - Sudhasri

图书馆长时间未得到维护。 - pratham kesarkar

这个库对我来说非常好用，除了在API 16上动画是方形而不是圆形。有人遇到过类似的问题吗？ - Marcin Jedynak

Answer 2

这是对Alejandro和BadYous答案的更新。

1. Best library is still Circular Reveal.

2. The right description is implementation 'com.github.ozodrukh:CircularReveal:2.0.1'

3. Use the right import for ViewAnimationUtils

    import io.codetail.animation.ViewAnimationUtils;
   

- Huseyin

Answer 3

是的！你可以使用CircularReveal库，就像@Alejandro所说的那样。

但是你需要修改库的依赖关系：

dependencies {
    compile 'com.github.ozodrukh:CircularReveal:1.1.1' //without "@aar" contrary to what the documentation says
}

否则，在某些运行于Lollipop版本之前的设备上，您将会遇到异常。

- Badr Yousfi

Answer 4

最好的库是：CircularReveal 使用：

使用普通的RevealFrameLayout和RevealLinearLayout。

<io.codetail.widget.RevealFrameLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <!-- Put more views here if you want, it's stock frame layout  -->

    <android.support.v7.widget.CardView
...
        />

</io.codetail.widget.RevealFrameLayout>

并且：

  View myView = findView(R.id.awesome_card);

    // get the center for the clipping circle
    int cx = (myView.getLeft() + myView.getRight()) / 2;
    int cy = (myView.getTop() + myView.getBottom()) / 2;

    // get the final radius for the clipping circle
    int finalRadius = Math.max(myView.getWidth(), myView.getHeight());

    SupportAnimator animator =
            ViewAnimationUtils.createCircularReveal(myView, cx, cy, 0, finalRadius);
    animator.setInterpolator(new AccelerateDecelerateInterpolator());
    animator.setDuration(1500);
    animator.start();

这个库很简单，在lollipop之前工作得非常好。

- Adnan Abdollah Zaki

---

这个能在Activity转换中使用吗？ - JayVDiyk

在转换结构中！我不这么认为，如果你找到了任何解决方案，请与我们分享。 - Adnan Abdollah Zaki

Answer 5

希望这能对你有所帮助...否则就使用这个http://pulse7.net/android/android-create-circular-reveal-animation-and-ripple-effect-like-whatsapp/。

compile ('com.github.ozodrukh:CircularReveal:1.1.1@aar') {
    transitive = true;

- Arjun Singh

Answer 6

我们不能在Lollipop之前的设备上使用Animator。 这是Animator.java文件。

package android.animation;

import java.util.ArrayList;

public abstract class Animator implements Cloneable {

/**
 * The set of listeners to be sent events through the life of an animation.
 */
ArrayList<AnimatorListener> mListeners = null;

/**
 * The set of listeners to be sent pause/resume events through the life
 * of an animation.
 */
ArrayList<AnimatorPauseListener> mPauseListeners = null;

/**
 * Whether this animator is currently in a paused state.
 */
boolean mPaused = false;

/**
 * Starts this animation. If the animation has a nonzero startDelay, the animation will start
 * running after that delay elapses. A non-delayed animation will have its initial
 * value(s) set immediately, followed by calls to
 * {@link AnimatorListener#onAnimationStart(Animator)} for any listeners of this animator.
 *
 * <p>The animation started by calling this method will be run on the thread that called
 * this method. This thread should have a Looper on it (a runtime exception will be thrown if
 * this is not the case). Also, if the animation will animate
 * properties of objects in the view hierarchy, then the calling thread should be the UI
 * thread for that view hierarchy.</p>
 *
 */
public void start() {
}

/**
 * Cancels the animation. Unlike {@link #end()}, <code>cancel()</code> causes the animation to
 * stop in its tracks, sending an
 * {@link android.animation.Animator.AnimatorListener#onAnimationCancel(Animator)} to
 * its listeners, followed by an
 * {@link android.animation.Animator.AnimatorListener#onAnimationEnd(Animator)} message.
 *
 * <p>This method must be called on the thread that is running the animation.</p>
 */
public void cancel() {
}

/**
 * Ends the animation. This causes the animation to assign the end value of the property being
 * animated, then calling the
 * {@link android.animation.Animator.AnimatorListener#onAnimationEnd(Animator)} method on
 * its listeners.
 *
 * <p>This method must be called on the thread that is running the animation.</p>
 */
public void end() {
}

/**
 * Pauses a running animation. This method should only be called on the same thread on
 * which the animation was started. If the animation has not yet been {@link
 * #isStarted() started} or has since ended, then the call is ignored. Paused
 * animations can be resumed by calling {@link #resume()}.
 *
 * @see #resume()
 * @see #isPaused()
 * @see AnimatorPauseListener
 */
public void pause() {
    if (isStarted() && !mPaused) {
        mPaused = true;
        if (mPauseListeners != null) {
            ArrayList<AnimatorPauseListener> tmpListeners =
                    (ArrayList<AnimatorPauseListener>) mPauseListeners.clone();
            int numListeners = tmpListeners.size();
            for (int i = 0; i < numListeners; ++i) {
                tmpListeners.get(i).onAnimationPause(this);
            }
        }
    }
}

/**
 * Resumes a paused animation, causing the animator to pick up where it left off
 * when it was paused. This method should only be called on the same thread on
 * which the animation was started. Calls to resume() on an animator that is
 * not currently paused will be ignored.
 *
 * @see #pause()
 * @see #isPaused()
 * @see AnimatorPauseListener
 */
public void resume() {
    if (mPaused) {
        mPaused = false;
        if (mPauseListeners != null) {
            ArrayList<AnimatorPauseListener> tmpListeners =
                    (ArrayList<AnimatorPauseListener>) mPauseListeners.clone();
            int numListeners = tmpListeners.size();
            for (int i = 0; i < numListeners; ++i) {
                tmpListeners.get(i).onAnimationResume(this);
            }
        }
    }
}

/**
 * Returns whether this animator is currently in a paused state.
 *
 * @return True if the animator is currently paused, false otherwise.
 *
 * @see #pause()
 * @see #resume()
 */
public boolean isPaused() {
    return mPaused;
}

/**
 * The amount of time, in milliseconds, to delay processing the animation
 * after {@link #start()} is called.
 *
 * @return the number of milliseconds to delay running the animation
 */
public abstract long getStartDelay();

/**
 * The amount of time, in milliseconds, to delay processing the animation
 * after {@link #start()} is called.

 * @param startDelay The amount of the delay, in milliseconds
 */
public abstract void setStartDelay(long startDelay);

/**
 * Sets the duration of the animation.
 *
 * @param duration The length of the animation, in milliseconds.
 */
public abstract Animator setDuration(long duration);

/**
 * Gets the duration of the animation.
 *
 * @return The length of the animation, in milliseconds.
 */
public abstract long getDuration();

/**
 * The time interpolator used in calculating the elapsed fraction of the
 * animation. The interpolator determines whether the animation runs with
 * linear or non-linear motion, such as acceleration and deceleration. The
 * default value is {@link android.view.animation.AccelerateDecelerateInterpolator}.
 *
 * @param value the interpolator to be used by this animation
 */
public abstract void setInterpolator(TimeInterpolator value);

/**
 * Returns the timing interpolator that this animation uses.
 *
 * @return The timing interpolator for this animation.
 */
public TimeInterpolator getInterpolator() {
    return null;
}

/**
 * Returns whether this Animator is currently running (having been started and gone past any
 * initial startDelay period and not yet ended).
 *
 * @return Whether the Animator is running.
 */
public abstract boolean isRunning();

/**
 * Returns whether this Animator has been started and not yet ended. This state is a superset
 * of the state of {@link #isRunning()}, because an Animator with a nonzero
 * {@link #getStartDelay() startDelay} will return true for {@link #isStarted()} during the
 * delay phase, whereas {@link #isRunning()} will return true only after the delay phase
 * is complete.
 *
 * @return Whether the Animator has been started and not yet ended.
 */
public boolean isStarted() {
    // Default method returns value for isRunning(). Subclasses should override to return a
    // real value.
    return isRunning();
}

/**
 * Adds a listener to the set of listeners that are sent events through the life of an
 * animation, such as start, repeat, and end.
 *
 * @param listener the listener to be added to the current set of listeners for this animation.
 */
public void addListener(AnimatorListener listener) {
    if (mListeners == null) {
        mListeners = new ArrayList<AnimatorListener>();
    }
    mListeners.add(listener);
}

/**
 * Removes a listener from the set listening to this animation.
 *
 * @param listener the listener to be removed from the current set of listeners for this
 *                 animation.
 */
public void removeListener(AnimatorListener listener) {
    if (mListeners == null) {
        return;
    }
    mListeners.remove(listener);
    if (mListeners.size() == 0) {
        mListeners = null;
    }
}

/**
 * Gets the set of {@link android.animation.Animator.AnimatorListener} objects that are currently
 * listening for events on this <code>Animator</code> object.
 *
 * @return ArrayList<AnimatorListener> The set of listeners.
 */
public ArrayList<AnimatorListener> getListeners() {
    return mListeners;
}

/**
 * Adds a pause listener to this animator.
 *
 * @param listener the listener to be added to the current set of pause listeners
 * for this animation.
 */
public void addPauseListener(AnimatorPauseListener listener) {
    if (mPauseListeners == null) {
        mPauseListeners = new ArrayList<AnimatorPauseListener>();
    }
    mPauseListeners.add(listener);
}

/**
 * Removes a pause listener from the set listening to this animation.
 *
 * @param listener the listener to be removed from the current set of pause
 * listeners for this animation.
 */
public void removePauseListener(AnimatorPauseListener listener) {
    if (mPauseListeners == null) {
        return;
    }
    mPauseListeners.remove(listener);
    if (mPauseListeners.size() == 0) {
        mPauseListeners = null;
    }
}

/**
 * Removes all {@link #addListener(android.animation.Animator.AnimatorListener) listeners}
 * and {@link #addPauseListener(android.animation.Animator.AnimatorPauseListener)
 * pauseListeners} from this object.
 */
public void removeAllListeners() {
    if (mListeners != null) {
        mListeners.clear();
        mListeners = null;
    }
    if (mPauseListeners != null) {
        mPauseListeners.clear();
        mPauseListeners = null;
    }
}

@Override
public Animator clone() {
    try {
        final Animator anim = (Animator) super.clone();
        if (mListeners != null) {
            ArrayList<AnimatorListener> oldListeners = mListeners;
            anim.mListeners = new ArrayList<AnimatorListener>();
            int numListeners = oldListeners.size();
            for (int i = 0; i < numListeners; ++i) {
                anim.mListeners.add(oldListeners.get(i));
            }
        }
        if (mPauseListeners != null) {
            ArrayList<AnimatorPauseListener> oldListeners = mPauseListeners;
            anim.mPauseListeners = new ArrayList<AnimatorPauseListener>();
            int numListeners = oldListeners.size();
            for (int i = 0; i < numListeners; ++i) {
                anim.mPauseListeners.add(oldListeners.get(i));
            }
        }
        return anim;
    } catch (CloneNotSupportedException e) {
       throw new AssertionError();
    }
}

/**
 * This method tells the object to use appropriate information to extract
 * starting values for the animation. For example, a AnimatorSet object will pass
 * this call to its child objects to tell them to set up the values. A
 * ObjectAnimator object will use the information it has about its target object
 * and PropertyValuesHolder objects to get the start values for its properties.
 * A ValueAnimator object will ignore the request since it does not have enough
 * information (such as a target object) to gather these values.
 */
public void setupStartValues() {
}

/**
 * This method tells the object to use appropriate information to extract
 * ending values for the animation. For example, a AnimatorSet object will pass
 * this call to its child objects to tell them to set up the values. A
 * ObjectAnimator object will use the information it has about its target object
 * and PropertyValuesHolder objects to get the start values for its properties.
 * A ValueAnimator object will ignore the request since it does not have enough
 * information (such as a target object) to gather these values.
 */
public void setupEndValues() {
}

/**
 * Sets the target object whose property will be animated by this animation. Not all subclasses
 * operate on target objects (for example, {@link ValueAnimator}, but this method
 * is on the superclass for the convenience of dealing generically with those subclasses
 * that do handle targets.
 *
 * @param target The object being animated
 */
public void setTarget(Object target) {
}

// Hide reverse() and canReverse() for now since reverse() only work for simple
// cases, like we don't support sequential, neither startDelay.
// TODO: make reverse() works for all the Animators.
/**
 * @hide
 */
public boolean canReverse() {
    return false;
}

/**
 * @hide
 */
public void reverse() {
    throw new IllegalStateException("Reverse is not supported");
}

/**
 * <p>An animation listener receives notifications from an animation.
 * Notifications indicate animation related events, such as the end or the
 * repetition of the animation.</p>
 */
public static interface AnimatorListener {
    /**
     * <p>Notifies the start of the animation.</p>
     *
     * @param animation The started animation.
     */
    void onAnimationStart(Animator animation);

    /**
     * <p>Notifies the end of the animation. This callback is not invoked
     * for animations with repeat count set to INFINITE.</p>
     *
     * @param animation The animation which reached its end.
     */
    void onAnimationEnd(Animator animation);

    /**
     * <p>Notifies the cancellation of the animation. This callback is not invoked
     * for animations with repeat count set to INFINITE.</p>
     *
     * @param animation The animation which was canceled.
     */
    void onAnimationCancel(Animator animation);

    /**
     * <p>Notifies the repetition of the animation.</p>
     *
     * @param animation The animation which was repeated.
     */
    void onAnimationRepeat(Animator animation);
}

/**
 * A pause listener receives notifications from an animation when the
 * animation is {@link #pause() paused} or {@link #resume() resumed}.
 *
 * @see #addPauseListener(AnimatorPauseListener)
 */
public static interface AnimatorPauseListener {
    /**
     * <p>Notifies that the animation was paused.</p>
     *
     * @param animation The animaton being paused.
     * @see #pause()
     */
    void onAnimationPause(Animator animation);

    /**
     * <p>Notifies that the animation was resumed, after being
     * previously paused.</p>
     *
     * @param animation The animation being resumed.
     * @see #resume()
     */
    void onAnimationResume(Animator animation);
}

/**
 * <p>Whether or not the Animator is allowed to run asynchronously off of
 * the UI thread. This is a hint that informs the Animator that it is
 * OK to run the animation off-thread, however the Animator may decide
 * that it must run the animation on the UI thread anyway.
 *
 * <p>Regardless of whether or not the animation runs asynchronously, all
 * listener callbacks will be called on the UI thread.</p>
 *
 * <p>To be able to use this hint the following must be true:</p>
 * <ol>
 * <li>The animator is immutable while {@link #isStarted()} is true. Requests
 *    to change duration, delay, etc... may be ignored.</li>
 * <li>Lifecycle callback events may be asynchronous. Events such as
 *    {@link Animator.AnimatorListener#onAnimationEnd(Animator)} or
 *    {@link Animator.AnimatorListener#onAnimationRepeat(Animator)} may end up delayed
 *    as they must be posted back to the UI thread, and any actions performed
 *    by those callbacks (such as starting new animations) will not happen
 *    in the same frame.</li>
 * <li>State change requests ({@link #cancel()}, {@link #end()}, {@link #reverse()}, etc...)
 *    may be asynchronous. It is guaranteed that all state changes that are
 *    performed on the UI thread in the same frame will be applied as a single
 *    atomic update, however that frame may be the current frame,
 *    the next frame, or some future frame. This will also impact the observed
 *    state of the Animator. For example, {@link #isStarted()} may still return true
 *    after a call to {@link #end()}. Using the lifecycle callbacks is preferred over
 *    queries to {@link #isStarted()}, {@link #isRunning()}, and {@link #isPaused()}
 *    for this reason.</li>
 * </ol>
 * @hide
 */
public void setAllowRunningAsynchronously(boolean mayRunAsync) {
    // It is up to subclasses to support this, if they can.
}
  }

- Eshan Singh

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有没有办法让它在Lollipop之前的版本中运行或类似的东西？ - JavierSegoviaCordoba

我希望它以后能被谷歌或其他人移植到较低的API，但在那之前没有办法。 - Eshan Singh

Answer 7

谷歌终于进行了移植。现在它位于Material Components库中，名称为CircularRevealCompat

- kyay10