1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.animation; 18 19 import android.annotation.CallSuper; 20 import android.os.Looper; 21 import android.os.Trace; 22 import android.util.AndroidRuntimeException; 23 import android.util.Log; 24 import android.view.Choreographer; 25 import android.view.animation.AccelerateDecelerateInterpolator; 26 import android.view.animation.AnimationUtils; 27 import android.view.animation.LinearInterpolator; 28 29 import java.util.ArrayList; 30 import java.util.HashMap; 31 32 /** 33 * This class provides a simple timing engine for running animations 34 * which calculate animated values and set them on target objects. 35 * 36 * <p>There is a single timing pulse that all animations use. It runs in a 37 * custom handler to ensure that property changes happen on the UI thread.</p> 38 * 39 * <p>By default, ValueAnimator uses non-linear time interpolation, via the 40 * {@link AccelerateDecelerateInterpolator} class, which accelerates into and decelerates 41 * out of an animation. This behavior can be changed by calling 42 * {@link ValueAnimator#setInterpolator(TimeInterpolator)}.</p> 43 * 44 * <p>Animators can be created from either code or resource files. Here is an example 45 * of a ValueAnimator resource file:</p> 46 * 47 * {@sample development/samples/ApiDemos/res/anim/animator.xml ValueAnimatorResources} 48 * 49 * <p>It is also possible to use a combination of {@link PropertyValuesHolder} and 50 * {@link Keyframe} resource tags to create a multi-step animation. 51 * Note that you can specify explicit fractional values (from 0 to 1) for 52 * each keyframe to determine when, in the overall duration, the animation should arrive at that 53 * value. Alternatively, you can leave the fractions off and the keyframes will be equally 54 * distributed within the total duration:</p> 55 * 56 * {@sample development/samples/ApiDemos/res/anim/value_animator_pvh_kf.xml 57 * ValueAnimatorKeyframeResources} 58 * 59 * <div class="special reference"> 60 * <h3>Developer Guides</h3> 61 * <p>For more information about animating with {@code ValueAnimator}, read the 62 * <a href="{@docRoot}guide/topics/graphics/prop-animation.html#value-animator">Property 63 * Animation</a> developer guide.</p> 64 * </div> 65 */ 66 @SuppressWarnings("unchecked") 67 public class ValueAnimator extends Animator { 68 private static final String TAG = "ValueAnimator"; 69 private static final boolean DEBUG = false; 70 71 /** 72 * Internal constants 73 */ 74 private static float sDurationScale = 1.0f; 75 76 /** 77 * Values used with internal variable mPlayingState to indicate the current state of an 78 * animation. 79 */ 80 static final int STOPPED = 0; // Not yet playing 81 static final int RUNNING = 1; // Playing normally 82 static final int SEEKED = 2; // Seeked to some time value 83 84 /** 85 * Internal variables 86 * NOTE: This object implements the clone() method, making a deep copy of any referenced 87 * objects. As other non-trivial fields are added to this class, make sure to add logic 88 * to clone() to make deep copies of them. 89 */ 90 91 /** 92 * The first time that the animation's animateFrame() method is called. This time is used to 93 * determine elapsed time (and therefore the elapsed fraction) in subsequent calls 94 * to animateFrame(). 95 * 96 * Whenever mStartTime is set, you must also update mStartTimeCommitted. 97 */ 98 long mStartTime; 99 100 /** 101 * When true, the start time has been firmly committed as a chosen reference point in 102 * time by which the progress of the animation will be evaluated. When false, the 103 * start time may be updated when the first animation frame is committed so as 104 * to compensate for jank that may have occurred between when the start time was 105 * initialized and when the frame was actually drawn. 106 * 107 * This flag is generally set to false during the first frame of the animation 108 * when the animation playing state transitions from STOPPED to RUNNING or 109 * resumes after having been paused. This flag is set to true when the start time 110 * is firmly committed and should not be further compensated for jank. 111 */ 112 boolean mStartTimeCommitted; 113 114 /** 115 * Set when setCurrentPlayTime() is called. If negative, animation is not currently seeked 116 * to a value. 117 */ 118 float mSeekFraction = -1; 119 120 /** 121 * Set on the next frame after pause() is called, used to calculate a new startTime 122 * or delayStartTime which allows the animator to continue from the point at which 123 * it was paused. If negative, has not yet been set. 124 */ 125 private long mPauseTime; 126 127 /** 128 * Set when an animator is resumed. This triggers logic in the next frame which 129 * actually resumes the animator. 130 */ 131 private boolean mResumed = false; 132 133 134 // The static sAnimationHandler processes the internal timing loop on which all animations 135 // are based 136 /** 137 * @hide 138 */ 139 protected static ThreadLocal<AnimationHandler> sAnimationHandler = 140 new ThreadLocal<AnimationHandler>(); 141 142 // The time interpolator to be used if none is set on the animation 143 private static final TimeInterpolator sDefaultInterpolator = 144 new AccelerateDecelerateInterpolator(); 145 146 /** 147 * Used to indicate whether the animation is currently playing in reverse. This causes the 148 * elapsed fraction to be inverted to calculate the appropriate values. 149 */ 150 private boolean mPlayingBackwards = false; 151 152 /** 153 * Flag to indicate whether this animator is playing in reverse mode, specifically 154 * by being started or interrupted by a call to reverse(). This flag is different than 155 * mPlayingBackwards, which indicates merely whether the current iteration of the 156 * animator is playing in reverse. It is used in corner cases to determine proper end 157 * behavior. 158 */ 159 private boolean mReversing; 160 161 /** 162 * This variable tracks the current iteration that is playing. When mCurrentIteration exceeds the 163 * repeatCount (if repeatCount!=INFINITE), the animation ends 164 */ 165 private int mCurrentIteration = 0; 166 167 /** 168 * Tracks current elapsed/eased fraction, for querying in getAnimatedFraction(). 169 */ 170 private float mCurrentFraction = 0f; 171 172 /** 173 * Tracks whether a startDelay'd animation has begun playing through the startDelay. 174 */ 175 private boolean mStartedDelay = false; 176 177 /** 178 * Tracks the time at which the animation began playing through its startDelay. This is 179 * different from the mStartTime variable, which is used to track when the animation became 180 * active (which is when the startDelay expired and the animation was added to the active 181 * animations list). 182 */ 183 private long mDelayStartTime; 184 185 /** 186 * Flag that represents the current state of the animation. Used to figure out when to start 187 * an animation (if state == STOPPED). Also used to end an animation that 188 * has been cancel()'d or end()'d since the last animation frame. Possible values are 189 * STOPPED, RUNNING, SEEKED. 190 */ 191 int mPlayingState = STOPPED; 192 193 /** 194 * Additional playing state to indicate whether an animator has been start()'d. There is 195 * some lag between a call to start() and the first animation frame. We should still note 196 * that the animation has been started, even if it's first animation frame has not yet 197 * happened, and reflect that state in isRunning(). 198 * Note that delayed animations are different: they are not started until their first 199 * animation frame, which occurs after their delay elapses. 200 */ 201 private boolean mRunning = false; 202 203 /** 204 * Additional playing state to indicate whether an animator has been start()'d, whether or 205 * not there is a nonzero startDelay. 206 */ 207 private boolean mStarted = false; 208 209 /** 210 * Tracks whether we've notified listeners of the onAnimationStart() event. This can be 211 * complex to keep track of since we notify listeners at different times depending on 212 * startDelay and whether start() was called before end(). 213 */ 214 private boolean mStartListenersCalled = false; 215 216 /** 217 * Flag that denotes whether the animation is set up and ready to go. Used to 218 * set up animation that has not yet been started. 219 */ 220 boolean mInitialized = false; 221 222 // 223 // Backing variables 224 // 225 226 // How long the animation should last in ms 227 private long mDuration = (long)(300 * sDurationScale); 228 private long mUnscaledDuration = 300; 229 230 // The amount of time in ms to delay starting the animation after start() is called 231 private long mStartDelay = 0; 232 private long mUnscaledStartDelay = 0; 233 234 // The number of times the animation will repeat. The default is 0, which means the animation 235 // will play only once 236 private int mRepeatCount = 0; 237 238 /** 239 * The type of repetition that will occur when repeatMode is nonzero. RESTART means the 240 * animation will start from the beginning on every new cycle. REVERSE means the animation 241 * will reverse directions on each iteration. 242 */ 243 private int mRepeatMode = RESTART; 244 245 /** 246 * The time interpolator to be used. The elapsed fraction of the animation will be passed 247 * through this interpolator to calculate the interpolated fraction, which is then used to 248 * calculate the animated values. 249 */ 250 private TimeInterpolator mInterpolator = sDefaultInterpolator; 251 252 /** 253 * The set of listeners to be sent events through the life of an animation. 254 */ 255 ArrayList<AnimatorUpdateListener> mUpdateListeners = null; 256 257 /** 258 * The property/value sets being animated. 259 */ 260 PropertyValuesHolder[] mValues; 261 262 /** 263 * A hashmap of the PropertyValuesHolder objects. This map is used to lookup animated values 264 * by property name during calls to getAnimatedValue(String). 265 */ 266 HashMap<String, PropertyValuesHolder> mValuesMap; 267 268 /** 269 * Public constants 270 */ 271 272 /** 273 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 274 * or a positive value, the animation restarts from the beginning. 275 */ 276 public static final int RESTART = 1; 277 /** 278 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 279 * or a positive value, the animation reverses direction on every iteration. 280 */ 281 public static final int REVERSE = 2; 282 /** 283 * This value used used with the {@link #setRepeatCount(int)} property to repeat 284 * the animation indefinitely. 285 */ 286 public static final int INFINITE = -1; 287 288 289 /** 290 * @hide 291 */ setDurationScale(float durationScale)292 public static void setDurationScale(float durationScale) { 293 sDurationScale = durationScale; 294 } 295 296 /** 297 * @hide 298 */ getDurationScale()299 public static float getDurationScale() { 300 return sDurationScale; 301 } 302 303 /** 304 * Creates a new ValueAnimator object. This default constructor is primarily for 305 * use internally; the factory methods which take parameters are more generally 306 * useful. 307 */ ValueAnimator()308 public ValueAnimator() { 309 } 310 311 /** 312 * Constructs and returns a ValueAnimator that animates between int values. A single 313 * value implies that that value is the one being animated to. However, this is not typically 314 * useful in a ValueAnimator object because there is no way for the object to determine the 315 * starting value for the animation (unlike ObjectAnimator, which can derive that value 316 * from the target object and property being animated). Therefore, there should typically 317 * be two or more values. 318 * 319 * @param values A set of values that the animation will animate between over time. 320 * @return A ValueAnimator object that is set up to animate between the given values. 321 */ ofInt(int... values)322 public static ValueAnimator ofInt(int... values) { 323 ValueAnimator anim = new ValueAnimator(); 324 anim.setIntValues(values); 325 return anim; 326 } 327 328 /** 329 * Constructs and returns a ValueAnimator that animates between color values. A single 330 * value implies that that value is the one being animated to. However, this is not typically 331 * useful in a ValueAnimator object because there is no way for the object to determine the 332 * starting value for the animation (unlike ObjectAnimator, which can derive that value 333 * from the target object and property being animated). Therefore, there should typically 334 * be two or more values. 335 * 336 * @param values A set of values that the animation will animate between over time. 337 * @return A ValueAnimator object that is set up to animate between the given values. 338 */ ofArgb(int... values)339 public static ValueAnimator ofArgb(int... values) { 340 ValueAnimator anim = new ValueAnimator(); 341 anim.setIntValues(values); 342 anim.setEvaluator(ArgbEvaluator.getInstance()); 343 return anim; 344 } 345 346 /** 347 * Constructs and returns a ValueAnimator that animates between float values. A single 348 * value implies that that value is the one being animated to. However, this is not typically 349 * useful in a ValueAnimator object because there is no way for the object to determine the 350 * starting value for the animation (unlike ObjectAnimator, which can derive that value 351 * from the target object and property being animated). Therefore, there should typically 352 * be two or more values. 353 * 354 * @param values A set of values that the animation will animate between over time. 355 * @return A ValueAnimator object that is set up to animate between the given values. 356 */ ofFloat(float... values)357 public static ValueAnimator ofFloat(float... values) { 358 ValueAnimator anim = new ValueAnimator(); 359 anim.setFloatValues(values); 360 return anim; 361 } 362 363 /** 364 * Constructs and returns a ValueAnimator that animates between the values 365 * specified in the PropertyValuesHolder objects. 366 * 367 * @param values A set of PropertyValuesHolder objects whose values will be animated 368 * between over time. 369 * @return A ValueAnimator object that is set up to animate between the given values. 370 */ ofPropertyValuesHolder(PropertyValuesHolder... values)371 public static ValueAnimator ofPropertyValuesHolder(PropertyValuesHolder... values) { 372 ValueAnimator anim = new ValueAnimator(); 373 anim.setValues(values); 374 return anim; 375 } 376 /** 377 * Constructs and returns a ValueAnimator that animates between Object values. A single 378 * value implies that that value is the one being animated to. However, this is not typically 379 * useful in a ValueAnimator object because there is no way for the object to determine the 380 * starting value for the animation (unlike ObjectAnimator, which can derive that value 381 * from the target object and property being animated). Therefore, there should typically 382 * be two or more values. 383 * 384 * <p>Since ValueAnimator does not know how to animate between arbitrary Objects, this 385 * factory method also takes a TypeEvaluator object that the ValueAnimator will use 386 * to perform that interpolation. 387 * 388 * @param evaluator A TypeEvaluator that will be called on each animation frame to 389 * provide the ncessry interpolation between the Object values to derive the animated 390 * value. 391 * @param values A set of values that the animation will animate between over time. 392 * @return A ValueAnimator object that is set up to animate between the given values. 393 */ ofObject(TypeEvaluator evaluator, Object... values)394 public static ValueAnimator ofObject(TypeEvaluator evaluator, Object... values) { 395 ValueAnimator anim = new ValueAnimator(); 396 anim.setObjectValues(values); 397 anim.setEvaluator(evaluator); 398 return anim; 399 } 400 401 /** 402 * Sets int values that will be animated between. A single 403 * value implies that that value is the one being animated to. However, this is not typically 404 * useful in a ValueAnimator object because there is no way for the object to determine the 405 * starting value for the animation (unlike ObjectAnimator, which can derive that value 406 * from the target object and property being animated). Therefore, there should typically 407 * be two or more values. 408 * 409 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 410 * than one PropertyValuesHolder object, this method will set the values for the first 411 * of those objects.</p> 412 * 413 * @param values A set of values that the animation will animate between over time. 414 */ setIntValues(int... values)415 public void setIntValues(int... values) { 416 if (values == null || values.length == 0) { 417 return; 418 } 419 if (mValues == null || mValues.length == 0) { 420 setValues(PropertyValuesHolder.ofInt("", values)); 421 } else { 422 PropertyValuesHolder valuesHolder = mValues[0]; 423 valuesHolder.setIntValues(values); 424 } 425 // New property/values/target should cause re-initialization prior to starting 426 mInitialized = false; 427 } 428 429 /** 430 * Sets float values that will be animated between. A single 431 * value implies that that value is the one being animated to. However, this is not typically 432 * useful in a ValueAnimator object because there is no way for the object to determine the 433 * starting value for the animation (unlike ObjectAnimator, which can derive that value 434 * from the target object and property being animated). Therefore, there should typically 435 * be two or more values. 436 * 437 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 438 * than one PropertyValuesHolder object, this method will set the values for the first 439 * of those objects.</p> 440 * 441 * @param values A set of values that the animation will animate between over time. 442 */ setFloatValues(float... values)443 public void setFloatValues(float... values) { 444 if (values == null || values.length == 0) { 445 return; 446 } 447 if (mValues == null || mValues.length == 0) { 448 setValues(PropertyValuesHolder.ofFloat("", values)); 449 } else { 450 PropertyValuesHolder valuesHolder = mValues[0]; 451 valuesHolder.setFloatValues(values); 452 } 453 // New property/values/target should cause re-initialization prior to starting 454 mInitialized = false; 455 } 456 457 /** 458 * Sets the values to animate between for this animation. A single 459 * value implies that that value is the one being animated to. However, this is not typically 460 * useful in a ValueAnimator object because there is no way for the object to determine the 461 * starting value for the animation (unlike ObjectAnimator, which can derive that value 462 * from the target object and property being animated). Therefore, there should typically 463 * be two or more values. 464 * 465 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 466 * than one PropertyValuesHolder object, this method will set the values for the first 467 * of those objects.</p> 468 * 469 * <p>There should be a TypeEvaluator set on the ValueAnimator that knows how to interpolate 470 * between these value objects. ValueAnimator only knows how to interpolate between the 471 * primitive types specified in the other setValues() methods.</p> 472 * 473 * @param values The set of values to animate between. 474 */ setObjectValues(Object... values)475 public void setObjectValues(Object... values) { 476 if (values == null || values.length == 0) { 477 return; 478 } 479 if (mValues == null || mValues.length == 0) { 480 setValues(PropertyValuesHolder.ofObject("", null, values)); 481 } else { 482 PropertyValuesHolder valuesHolder = mValues[0]; 483 valuesHolder.setObjectValues(values); 484 } 485 // New property/values/target should cause re-initialization prior to starting 486 mInitialized = false; 487 } 488 489 /** 490 * Sets the values, per property, being animated between. This function is called internally 491 * by the constructors of ValueAnimator that take a list of values. But a ValueAnimator can 492 * be constructed without values and this method can be called to set the values manually 493 * instead. 494 * 495 * @param values The set of values, per property, being animated between. 496 */ setValues(PropertyValuesHolder... values)497 public void setValues(PropertyValuesHolder... values) { 498 int numValues = values.length; 499 mValues = values; 500 mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 501 for (int i = 0; i < numValues; ++i) { 502 PropertyValuesHolder valuesHolder = values[i]; 503 mValuesMap.put(valuesHolder.getPropertyName(), valuesHolder); 504 } 505 // New property/values/target should cause re-initialization prior to starting 506 mInitialized = false; 507 } 508 509 /** 510 * Returns the values that this ValueAnimator animates between. These values are stored in 511 * PropertyValuesHolder objects, even if the ValueAnimator was created with a simple list 512 * of value objects instead. 513 * 514 * @return PropertyValuesHolder[] An array of PropertyValuesHolder objects which hold the 515 * values, per property, that define the animation. 516 */ getValues()517 public PropertyValuesHolder[] getValues() { 518 return mValues; 519 } 520 521 /** 522 * This function is called immediately before processing the first animation 523 * frame of an animation. If there is a nonzero <code>startDelay</code>, the 524 * function is called after that delay ends. 525 * It takes care of the final initialization steps for the 526 * animation. 527 * 528 * <p>Overrides of this method should call the superclass method to ensure 529 * that internal mechanisms for the animation are set up correctly.</p> 530 */ 531 @CallSuper initAnimation()532 void initAnimation() { 533 if (!mInitialized) { 534 int numValues = mValues.length; 535 for (int i = 0; i < numValues; ++i) { 536 mValues[i].init(); 537 } 538 mInitialized = true; 539 } 540 } 541 542 543 /** 544 * Sets the length of the animation. The default duration is 300 milliseconds. 545 * 546 * @param duration The length of the animation, in milliseconds. This value cannot 547 * be negative. 548 * @return ValueAnimator The object called with setDuration(). This return 549 * value makes it easier to compose statements together that construct and then set the 550 * duration, as in <code>ValueAnimator.ofInt(0, 10).setDuration(500).start()</code>. 551 */ 552 @Override setDuration(long duration)553 public ValueAnimator setDuration(long duration) { 554 if (duration < 0) { 555 throw new IllegalArgumentException("Animators cannot have negative duration: " + 556 duration); 557 } 558 mUnscaledDuration = duration; 559 updateScaledDuration(); 560 return this; 561 } 562 updateScaledDuration()563 private void updateScaledDuration() { 564 mDuration = (long)(mUnscaledDuration * sDurationScale); 565 } 566 567 /** 568 * Gets the length of the animation. The default duration is 300 milliseconds. 569 * 570 * @return The length of the animation, in milliseconds. 571 */ 572 @Override getDuration()573 public long getDuration() { 574 return mUnscaledDuration; 575 } 576 577 /** 578 * Sets the position of the animation to the specified point in time. This time should 579 * be between 0 and the total duration of the animation, including any repetition. If 580 * the animation has not yet been started, then it will not advance forward after it is 581 * set to this time; it will simply set the time to this value and perform any appropriate 582 * actions based on that time. If the animation is already running, then setCurrentPlayTime() 583 * will set the current playing time to this value and continue playing from that point. 584 * 585 * @param playTime The time, in milliseconds, to which the animation is advanced or rewound. 586 */ setCurrentPlayTime(long playTime)587 public void setCurrentPlayTime(long playTime) { 588 float fraction = mUnscaledDuration > 0 ? (float) playTime / mUnscaledDuration : 1; 589 setCurrentFraction(fraction); 590 } 591 592 /** 593 * Sets the position of the animation to the specified fraction. This fraction should 594 * be between 0 and the total fraction of the animation, including any repetition. That is, 595 * a fraction of 0 will position the animation at the beginning, a value of 1 at the end, 596 * and a value of 2 at the end of a reversing animator that repeats once. If 597 * the animation has not yet been started, then it will not advance forward after it is 598 * set to this fraction; it will simply set the fraction to this value and perform any 599 * appropriate actions based on that fraction. If the animation is already running, then 600 * setCurrentFraction() will set the current fraction to this value and continue 601 * playing from that point. {@link Animator.AnimatorListener} events are not called 602 * due to changing the fraction; those events are only processed while the animation 603 * is running. 604 * 605 * @param fraction The fraction to which the animation is advanced or rewound. Values 606 * outside the range of 0 to the maximum fraction for the animator will be clamped to 607 * the correct range. 608 */ setCurrentFraction(float fraction)609 public void setCurrentFraction(float fraction) { 610 initAnimation(); 611 if (fraction < 0) { 612 fraction = 0; 613 } 614 int iteration = (int) fraction; 615 if (fraction == 1) { 616 iteration -= 1; 617 } else if (fraction > 1) { 618 if (iteration < (mRepeatCount + 1) || mRepeatCount == INFINITE) { 619 if (mRepeatMode == REVERSE) { 620 mPlayingBackwards = (iteration % 2) != 0; 621 } 622 fraction = fraction % 1f; 623 } else { 624 fraction = 1; 625 iteration -= 1; 626 } 627 } else { 628 mPlayingBackwards = mReversing; 629 } 630 mCurrentIteration = iteration; 631 long seekTime = (long) (mDuration * fraction); 632 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 633 mStartTime = currentTime - seekTime; 634 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 635 if (mPlayingState != RUNNING) { 636 mSeekFraction = fraction; 637 mPlayingState = SEEKED; 638 } 639 if (mPlayingBackwards) { 640 fraction = 1f - fraction; 641 } 642 animateValue(fraction); 643 } 644 645 /** 646 * Gets the current position of the animation in time, which is equal to the current 647 * time minus the time that the animation started. An animation that is not yet started will 648 * return a value of zero. 649 * 650 * @return The current position in time of the animation. 651 */ getCurrentPlayTime()652 public long getCurrentPlayTime() { 653 if (!mInitialized || mPlayingState == STOPPED) { 654 return 0; 655 } 656 return AnimationUtils.currentAnimationTimeMillis() - mStartTime; 657 } 658 659 /** 660 * This custom, static handler handles the timing pulse that is shared by 661 * all active animations. This approach ensures that the setting of animation 662 * values will happen on the UI thread and that all animations will share 663 * the same times for calculating their values, which makes synchronizing 664 * animations possible. 665 * 666 * The handler uses the Choreographer for executing periodic callbacks. 667 * 668 * @hide 669 */ 670 @SuppressWarnings("unchecked") 671 protected static class AnimationHandler { 672 // The per-thread list of all active animations 673 /** @hide */ 674 protected final ArrayList<ValueAnimator> mAnimations = new ArrayList<ValueAnimator>(); 675 676 // Used in doAnimationFrame() to avoid concurrent modifications of mAnimations 677 private final ArrayList<ValueAnimator> mTmpAnimations = new ArrayList<ValueAnimator>(); 678 679 // The per-thread set of animations to be started on the next animation frame 680 /** @hide */ 681 protected final ArrayList<ValueAnimator> mPendingAnimations = new ArrayList<ValueAnimator>(); 682 683 /** 684 * Internal per-thread collections used to avoid set collisions as animations start and end 685 * while being processed. 686 * @hide 687 */ 688 protected final ArrayList<ValueAnimator> mDelayedAnims = new ArrayList<ValueAnimator>(); 689 private final ArrayList<ValueAnimator> mEndingAnims = new ArrayList<ValueAnimator>(); 690 private final ArrayList<ValueAnimator> mReadyAnims = new ArrayList<ValueAnimator>(); 691 692 private final Choreographer mChoreographer; 693 private boolean mAnimationScheduled; 694 private long mLastFrameTime; 695 AnimationHandler()696 private AnimationHandler() { 697 mChoreographer = Choreographer.getInstance(); 698 } 699 700 /** 701 * Start animating on the next frame. 702 */ start()703 public void start() { 704 scheduleAnimation(); 705 } 706 doAnimationFrame(long frameTime)707 void doAnimationFrame(long frameTime) { 708 mLastFrameTime = frameTime; 709 710 // mPendingAnimations holds any animations that have requested to be started 711 // We're going to clear mPendingAnimations, but starting animation may 712 // cause more to be added to the pending list (for example, if one animation 713 // starting triggers another starting). So we loop until mPendingAnimations 714 // is empty. 715 while (mPendingAnimations.size() > 0) { 716 ArrayList<ValueAnimator> pendingCopy = 717 (ArrayList<ValueAnimator>) mPendingAnimations.clone(); 718 mPendingAnimations.clear(); 719 int count = pendingCopy.size(); 720 for (int i = 0; i < count; ++i) { 721 ValueAnimator anim = pendingCopy.get(i); 722 // If the animation has a startDelay, place it on the delayed list 723 if (anim.mStartDelay == 0) { 724 anim.startAnimation(this); 725 } else { 726 mDelayedAnims.add(anim); 727 } 728 } 729 } 730 731 // Next, process animations currently sitting on the delayed queue, adding 732 // them to the active animations if they are ready 733 int numDelayedAnims = mDelayedAnims.size(); 734 for (int i = 0; i < numDelayedAnims; ++i) { 735 ValueAnimator anim = mDelayedAnims.get(i); 736 if (anim.delayedAnimationFrame(frameTime)) { 737 mReadyAnims.add(anim); 738 } 739 } 740 int numReadyAnims = mReadyAnims.size(); 741 if (numReadyAnims > 0) { 742 for (int i = 0; i < numReadyAnims; ++i) { 743 ValueAnimator anim = mReadyAnims.get(i); 744 anim.startAnimation(this); 745 anim.mRunning = true; 746 mDelayedAnims.remove(anim); 747 } 748 mReadyAnims.clear(); 749 } 750 751 // Now process all active animations. The return value from animationFrame() 752 // tells the handler whether it should now be ended 753 int numAnims = mAnimations.size(); 754 for (int i = 0; i < numAnims; ++i) { 755 mTmpAnimations.add(mAnimations.get(i)); 756 } 757 for (int i = 0; i < numAnims; ++i) { 758 ValueAnimator anim = mTmpAnimations.get(i); 759 if (mAnimations.contains(anim) && anim.doAnimationFrame(frameTime)) { 760 mEndingAnims.add(anim); 761 } 762 } 763 mTmpAnimations.clear(); 764 if (mEndingAnims.size() > 0) { 765 for (int i = 0; i < mEndingAnims.size(); ++i) { 766 mEndingAnims.get(i).endAnimation(this); 767 } 768 mEndingAnims.clear(); 769 } 770 771 // Schedule final commit for the frame. 772 mChoreographer.postCallback(Choreographer.CALLBACK_COMMIT, mCommit, null); 773 774 // If there are still active or delayed animations, schedule a future call to 775 // onAnimate to process the next frame of the animations. 776 if (!mAnimations.isEmpty() || !mDelayedAnims.isEmpty()) { 777 scheduleAnimation(); 778 } 779 } 780 commitAnimationFrame(long frameTime)781 void commitAnimationFrame(long frameTime) { 782 final long adjustment = frameTime - mLastFrameTime; 783 final int numAnims = mAnimations.size(); 784 for (int i = 0; i < numAnims; ++i) { 785 mAnimations.get(i).commitAnimationFrame(adjustment); 786 } 787 } 788 scheduleAnimation()789 private void scheduleAnimation() { 790 if (!mAnimationScheduled) { 791 mChoreographer.postCallback(Choreographer.CALLBACK_ANIMATION, mAnimate, null); 792 mAnimationScheduled = true; 793 } 794 } 795 796 // Called by the Choreographer. 797 final Runnable mAnimate = new Runnable() { 798 @Override 799 public void run() { 800 mAnimationScheduled = false; 801 doAnimationFrame(mChoreographer.getFrameTime()); 802 } 803 }; 804 805 // Called by the Choreographer. 806 final Runnable mCommit = new Runnable() { 807 @Override 808 public void run() { 809 commitAnimationFrame(mChoreographer.getFrameTime()); 810 } 811 }; 812 } 813 814 /** 815 * The amount of time, in milliseconds, to delay starting the animation after 816 * {@link #start()} is called. 817 * 818 * @return the number of milliseconds to delay running the animation 819 */ 820 @Override getStartDelay()821 public long getStartDelay() { 822 return mUnscaledStartDelay; 823 } 824 825 /** 826 * The amount of time, in milliseconds, to delay starting the animation after 827 * {@link #start()} is called. 828 829 * @param startDelay The amount of the delay, in milliseconds 830 */ 831 @Override setStartDelay(long startDelay)832 public void setStartDelay(long startDelay) { 833 this.mStartDelay = (long)(startDelay * sDurationScale); 834 mUnscaledStartDelay = startDelay; 835 } 836 837 /** 838 * The amount of time, in milliseconds, between each frame of the animation. This is a 839 * requested time that the animation will attempt to honor, but the actual delay between 840 * frames may be different, depending on system load and capabilities. This is a static 841 * function because the same delay will be applied to all animations, since they are all 842 * run off of a single timing loop. 843 * 844 * The frame delay may be ignored when the animation system uses an external timing 845 * source, such as the display refresh rate (vsync), to govern animations. 846 * 847 * @return the requested time between frames, in milliseconds 848 */ getFrameDelay()849 public static long getFrameDelay() { 850 return Choreographer.getFrameDelay(); 851 } 852 853 /** 854 * The amount of time, in milliseconds, between each frame of the animation. This is a 855 * requested time that the animation will attempt to honor, but the actual delay between 856 * frames may be different, depending on system load and capabilities. This is a static 857 * function because the same delay will be applied to all animations, since they are all 858 * run off of a single timing loop. 859 * 860 * The frame delay may be ignored when the animation system uses an external timing 861 * source, such as the display refresh rate (vsync), to govern animations. 862 * 863 * @param frameDelay the requested time between frames, in milliseconds 864 */ setFrameDelay(long frameDelay)865 public static void setFrameDelay(long frameDelay) { 866 Choreographer.setFrameDelay(frameDelay); 867 } 868 869 /** 870 * The most recent value calculated by this <code>ValueAnimator</code> when there is just one 871 * property being animated. This value is only sensible while the animation is running. The main 872 * purpose for this read-only property is to retrieve the value from the <code>ValueAnimator</code> 873 * during a call to {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 874 * is called during each animation frame, immediately after the value is calculated. 875 * 876 * @return animatedValue The value most recently calculated by this <code>ValueAnimator</code> for 877 * the single property being animated. If there are several properties being animated 878 * (specified by several PropertyValuesHolder objects in the constructor), this function 879 * returns the animated value for the first of those objects. 880 */ getAnimatedValue()881 public Object getAnimatedValue() { 882 if (mValues != null && mValues.length > 0) { 883 return mValues[0].getAnimatedValue(); 884 } 885 // Shouldn't get here; should always have values unless ValueAnimator was set up wrong 886 return null; 887 } 888 889 /** 890 * The most recent value calculated by this <code>ValueAnimator</code> for <code>propertyName</code>. 891 * The main purpose for this read-only property is to retrieve the value from the 892 * <code>ValueAnimator</code> during a call to 893 * {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 894 * is called during each animation frame, immediately after the value is calculated. 895 * 896 * @return animatedValue The value most recently calculated for the named property 897 * by this <code>ValueAnimator</code>. 898 */ getAnimatedValue(String propertyName)899 public Object getAnimatedValue(String propertyName) { 900 PropertyValuesHolder valuesHolder = mValuesMap.get(propertyName); 901 if (valuesHolder != null) { 902 return valuesHolder.getAnimatedValue(); 903 } else { 904 // At least avoid crashing if called with bogus propertyName 905 return null; 906 } 907 } 908 909 /** 910 * Sets how many times the animation should be repeated. If the repeat 911 * count is 0, the animation is never repeated. If the repeat count is 912 * greater than 0 or {@link #INFINITE}, the repeat mode will be taken 913 * into account. The repeat count is 0 by default. 914 * 915 * @param value the number of times the animation should be repeated 916 */ setRepeatCount(int value)917 public void setRepeatCount(int value) { 918 mRepeatCount = value; 919 } 920 /** 921 * Defines how many times the animation should repeat. The default value 922 * is 0. 923 * 924 * @return the number of times the animation should repeat, or {@link #INFINITE} 925 */ getRepeatCount()926 public int getRepeatCount() { 927 return mRepeatCount; 928 } 929 930 /** 931 * Defines what this animation should do when it reaches the end. This 932 * setting is applied only when the repeat count is either greater than 933 * 0 or {@link #INFINITE}. Defaults to {@link #RESTART}. 934 * 935 * @param value {@link #RESTART} or {@link #REVERSE} 936 */ setRepeatMode(int value)937 public void setRepeatMode(int value) { 938 mRepeatMode = value; 939 } 940 941 /** 942 * Defines what this animation should do when it reaches the end. 943 * 944 * @return either one of {@link #REVERSE} or {@link #RESTART} 945 */ getRepeatMode()946 public int getRepeatMode() { 947 return mRepeatMode; 948 } 949 950 /** 951 * Adds a listener to the set of listeners that are sent update events through the life of 952 * an animation. This method is called on all listeners for every frame of the animation, 953 * after the values for the animation have been calculated. 954 * 955 * @param listener the listener to be added to the current set of listeners for this animation. 956 */ addUpdateListener(AnimatorUpdateListener listener)957 public void addUpdateListener(AnimatorUpdateListener listener) { 958 if (mUpdateListeners == null) { 959 mUpdateListeners = new ArrayList<AnimatorUpdateListener>(); 960 } 961 mUpdateListeners.add(listener); 962 } 963 964 /** 965 * Removes all listeners from the set listening to frame updates for this animation. 966 */ removeAllUpdateListeners()967 public void removeAllUpdateListeners() { 968 if (mUpdateListeners == null) { 969 return; 970 } 971 mUpdateListeners.clear(); 972 mUpdateListeners = null; 973 } 974 975 /** 976 * Removes a listener from the set listening to frame updates for this animation. 977 * 978 * @param listener the listener to be removed from the current set of update listeners 979 * for this animation. 980 */ removeUpdateListener(AnimatorUpdateListener listener)981 public void removeUpdateListener(AnimatorUpdateListener listener) { 982 if (mUpdateListeners == null) { 983 return; 984 } 985 mUpdateListeners.remove(listener); 986 if (mUpdateListeners.size() == 0) { 987 mUpdateListeners = null; 988 } 989 } 990 991 992 /** 993 * The time interpolator used in calculating the elapsed fraction of this animation. The 994 * interpolator determines whether the animation runs with linear or non-linear motion, 995 * such as acceleration and deceleration. The default value is 996 * {@link android.view.animation.AccelerateDecelerateInterpolator} 997 * 998 * @param value the interpolator to be used by this animation. A value of <code>null</code> 999 * will result in linear interpolation. 1000 */ 1001 @Override setInterpolator(TimeInterpolator value)1002 public void setInterpolator(TimeInterpolator value) { 1003 if (value != null) { 1004 mInterpolator = value; 1005 } else { 1006 mInterpolator = new LinearInterpolator(); 1007 } 1008 } 1009 1010 /** 1011 * Returns the timing interpolator that this ValueAnimator uses. 1012 * 1013 * @return The timing interpolator for this ValueAnimator. 1014 */ 1015 @Override getInterpolator()1016 public TimeInterpolator getInterpolator() { 1017 return mInterpolator; 1018 } 1019 1020 /** 1021 * The type evaluator to be used when calculating the animated values of this animation. 1022 * The system will automatically assign a float or int evaluator based on the type 1023 * of <code>startValue</code> and <code>endValue</code> in the constructor. But if these values 1024 * are not one of these primitive types, or if different evaluation is desired (such as is 1025 * necessary with int values that represent colors), a custom evaluator needs to be assigned. 1026 * For example, when running an animation on color values, the {@link ArgbEvaluator} 1027 * should be used to get correct RGB color interpolation. 1028 * 1029 * <p>If this ValueAnimator has only one set of values being animated between, this evaluator 1030 * will be used for that set. If there are several sets of values being animated, which is 1031 * the case if PropertyValuesHolder objects were set on the ValueAnimator, then the evaluator 1032 * is assigned just to the first PropertyValuesHolder object.</p> 1033 * 1034 * @param value the evaluator to be used this animation 1035 */ setEvaluator(TypeEvaluator value)1036 public void setEvaluator(TypeEvaluator value) { 1037 if (value != null && mValues != null && mValues.length > 0) { 1038 mValues[0].setEvaluator(value); 1039 } 1040 } 1041 notifyStartListeners()1042 private void notifyStartListeners() { 1043 if (mListeners != null && !mStartListenersCalled) { 1044 ArrayList<AnimatorListener> tmpListeners = 1045 (ArrayList<AnimatorListener>) mListeners.clone(); 1046 int numListeners = tmpListeners.size(); 1047 for (int i = 0; i < numListeners; ++i) { 1048 tmpListeners.get(i).onAnimationStart(this); 1049 } 1050 } 1051 mStartListenersCalled = true; 1052 } 1053 1054 /** 1055 * Start the animation playing. This version of start() takes a boolean flag that indicates 1056 * whether the animation should play in reverse. The flag is usually false, but may be set 1057 * to true if called from the reverse() method. 1058 * 1059 * <p>The animation started by calling this method will be run on the thread that called 1060 * this method. This thread should have a Looper on it (a runtime exception will be thrown if 1061 * this is not the case). Also, if the animation will animate 1062 * properties of objects in the view hierarchy, then the calling thread should be the UI 1063 * thread for that view hierarchy.</p> 1064 * 1065 * @param playBackwards Whether the ValueAnimator should start playing in reverse. 1066 */ start(boolean playBackwards)1067 private void start(boolean playBackwards) { 1068 if (Looper.myLooper() == null) { 1069 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 1070 } 1071 mReversing = playBackwards; 1072 mPlayingBackwards = playBackwards; 1073 if (playBackwards && mSeekFraction != -1) { 1074 if (mSeekFraction == 0 && mCurrentIteration == 0) { 1075 // special case: reversing from seek-to-0 should act as if not seeked at all 1076 mSeekFraction = 0; 1077 } else if (mRepeatCount == INFINITE) { 1078 mSeekFraction = 1 - (mSeekFraction % 1); 1079 } else { 1080 mSeekFraction = 1 + mRepeatCount - (mCurrentIteration + mSeekFraction); 1081 } 1082 mCurrentIteration = (int) mSeekFraction; 1083 mSeekFraction = mSeekFraction % 1; 1084 } 1085 if (mCurrentIteration > 0 && mRepeatMode == REVERSE && 1086 (mCurrentIteration < (mRepeatCount + 1) || mRepeatCount == INFINITE)) { 1087 // if we were seeked to some other iteration in a reversing animator, 1088 // figure out the correct direction to start playing based on the iteration 1089 if (playBackwards) { 1090 mPlayingBackwards = (mCurrentIteration % 2) == 0; 1091 } else { 1092 mPlayingBackwards = (mCurrentIteration % 2) != 0; 1093 } 1094 } 1095 int prevPlayingState = mPlayingState; 1096 mPlayingState = STOPPED; 1097 mStarted = true; 1098 mStartedDelay = false; 1099 mPaused = false; 1100 updateScaledDuration(); // in case the scale factor has changed since creation time 1101 AnimationHandler animationHandler = getOrCreateAnimationHandler(); 1102 animationHandler.mPendingAnimations.add(this); 1103 if (mStartDelay == 0) { 1104 // This sets the initial value of the animation, prior to actually starting it running 1105 if (prevPlayingState != SEEKED) { 1106 setCurrentPlayTime(0); 1107 } 1108 mPlayingState = STOPPED; 1109 mRunning = true; 1110 notifyStartListeners(); 1111 } 1112 animationHandler.start(); 1113 } 1114 1115 @Override start()1116 public void start() { 1117 start(false); 1118 } 1119 1120 @Override cancel()1121 public void cancel() { 1122 // Only cancel if the animation is actually running or has been started and is about 1123 // to run 1124 AnimationHandler handler = getOrCreateAnimationHandler(); 1125 if (mPlayingState != STOPPED 1126 || handler.mPendingAnimations.contains(this) 1127 || handler.mDelayedAnims.contains(this)) { 1128 // Only notify listeners if the animator has actually started 1129 if ((mStarted || mRunning) && mListeners != null) { 1130 if (!mRunning) { 1131 // If it's not yet running, then start listeners weren't called. Call them now. 1132 notifyStartListeners(); 1133 } 1134 ArrayList<AnimatorListener> tmpListeners = 1135 (ArrayList<AnimatorListener>) mListeners.clone(); 1136 for (AnimatorListener listener : tmpListeners) { 1137 listener.onAnimationCancel(this); 1138 } 1139 } 1140 endAnimation(handler); 1141 } 1142 } 1143 1144 @Override end()1145 public void end() { 1146 AnimationHandler handler = getOrCreateAnimationHandler(); 1147 if (!handler.mAnimations.contains(this) && !handler.mPendingAnimations.contains(this)) { 1148 // Special case if the animation has not yet started; get it ready for ending 1149 mStartedDelay = false; 1150 startAnimation(handler); 1151 mStarted = true; 1152 } else if (!mInitialized) { 1153 initAnimation(); 1154 } 1155 animateValue(mPlayingBackwards ? 0f : 1f); 1156 endAnimation(handler); 1157 } 1158 1159 @Override resume()1160 public void resume() { 1161 if (mPaused) { 1162 mResumed = true; 1163 } 1164 super.resume(); 1165 } 1166 1167 @Override pause()1168 public void pause() { 1169 boolean previouslyPaused = mPaused; 1170 super.pause(); 1171 if (!previouslyPaused && mPaused) { 1172 mPauseTime = -1; 1173 mResumed = false; 1174 } 1175 } 1176 1177 @Override isRunning()1178 public boolean isRunning() { 1179 return (mPlayingState == RUNNING || mRunning); 1180 } 1181 1182 @Override isStarted()1183 public boolean isStarted() { 1184 return mStarted; 1185 } 1186 1187 /** 1188 * Plays the ValueAnimator in reverse. If the animation is already running, 1189 * it will stop itself and play backwards from the point reached when reverse was called. 1190 * If the animation is not currently running, then it will start from the end and 1191 * play backwards. This behavior is only set for the current animation; future playing 1192 * of the animation will use the default behavior of playing forward. 1193 */ 1194 @Override reverse()1195 public void reverse() { 1196 mPlayingBackwards = !mPlayingBackwards; 1197 if (mPlayingState == RUNNING) { 1198 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 1199 long currentPlayTime = currentTime - mStartTime; 1200 long timeLeft = mDuration - currentPlayTime; 1201 mStartTime = currentTime - timeLeft; 1202 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 1203 mReversing = !mReversing; 1204 } else if (mStarted) { 1205 end(); 1206 } else { 1207 start(true); 1208 } 1209 } 1210 1211 /** 1212 * @hide 1213 */ 1214 @Override canReverse()1215 public boolean canReverse() { 1216 return true; 1217 } 1218 1219 /** 1220 * Called internally to end an animation by removing it from the animations list. Must be 1221 * called on the UI thread. 1222 * @hide 1223 */ endAnimation(AnimationHandler handler)1224 protected void endAnimation(AnimationHandler handler) { 1225 handler.mAnimations.remove(this); 1226 handler.mPendingAnimations.remove(this); 1227 handler.mDelayedAnims.remove(this); 1228 mPlayingState = STOPPED; 1229 mPaused = false; 1230 if ((mStarted || mRunning) && mListeners != null) { 1231 if (!mRunning) { 1232 // If it's not yet running, then start listeners weren't called. Call them now. 1233 notifyStartListeners(); 1234 } 1235 ArrayList<AnimatorListener> tmpListeners = 1236 (ArrayList<AnimatorListener>) mListeners.clone(); 1237 int numListeners = tmpListeners.size(); 1238 for (int i = 0; i < numListeners; ++i) { 1239 tmpListeners.get(i).onAnimationEnd(this); 1240 } 1241 } 1242 mRunning = false; 1243 mStarted = false; 1244 mStartListenersCalled = false; 1245 mPlayingBackwards = false; 1246 mReversing = false; 1247 mCurrentIteration = 0; 1248 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1249 Trace.asyncTraceEnd(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1250 System.identityHashCode(this)); 1251 } 1252 } 1253 1254 /** 1255 * Called internally to start an animation by adding it to the active animations list. Must be 1256 * called on the UI thread. 1257 */ startAnimation(AnimationHandler handler)1258 private void startAnimation(AnimationHandler handler) { 1259 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1260 Trace.asyncTraceBegin(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1261 System.identityHashCode(this)); 1262 } 1263 initAnimation(); 1264 handler.mAnimations.add(this); 1265 if (mStartDelay > 0 && mListeners != null) { 1266 // Listeners were already notified in start() if startDelay is 0; this is 1267 // just for delayed animations 1268 notifyStartListeners(); 1269 } 1270 } 1271 1272 /** 1273 * Returns the name of this animator for debugging purposes. 1274 */ getNameForTrace()1275 String getNameForTrace() { 1276 return "animator"; 1277 } 1278 1279 1280 /** 1281 * Internal function called to process an animation frame on an animation that is currently 1282 * sleeping through its <code>startDelay</code> phase. The return value indicates whether it 1283 * should be woken up and put on the active animations queue. 1284 * 1285 * @param currentTime The current animation time, used to calculate whether the animation 1286 * has exceeded its <code>startDelay</code> and should be started. 1287 * @return True if the animation's <code>startDelay</code> has been exceeded and the animation 1288 * should be added to the set of active animations. 1289 */ delayedAnimationFrame(long currentTime)1290 private boolean delayedAnimationFrame(long currentTime) { 1291 if (!mStartedDelay) { 1292 mStartedDelay = true; 1293 mDelayStartTime = currentTime; 1294 } 1295 if (mPaused) { 1296 if (mPauseTime < 0) { 1297 mPauseTime = currentTime; 1298 } 1299 return false; 1300 } else if (mResumed) { 1301 mResumed = false; 1302 if (mPauseTime > 0) { 1303 // Offset by the duration that the animation was paused 1304 mDelayStartTime += (currentTime - mPauseTime); 1305 } 1306 } 1307 long deltaTime = currentTime - mDelayStartTime; 1308 if (deltaTime > mStartDelay) { 1309 // startDelay ended - start the anim and record the mStartTime appropriately 1310 mStartTime = mDelayStartTime + mStartDelay; 1311 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 1312 mPlayingState = RUNNING; 1313 return true; 1314 } 1315 return false; 1316 } 1317 1318 /** 1319 * Applies an adjustment to the animation to compensate for jank between when 1320 * the animation first ran and when the frame was drawn. 1321 */ commitAnimationFrame(long adjustment)1322 void commitAnimationFrame(long adjustment) { 1323 if (!mStartTimeCommitted) { 1324 mStartTimeCommitted = true; 1325 if (mPlayingState == RUNNING && adjustment > 0) { 1326 mStartTime += adjustment; 1327 if (DEBUG) { 1328 Log.d(TAG, "Adjusted start time by " + adjustment + " ms: " + toString()); 1329 } 1330 } 1331 } 1332 } 1333 1334 /** 1335 * This internal function processes a single animation frame for a given animation. The 1336 * currentTime parameter is the timing pulse sent by the handler, used to calculate the 1337 * elapsed duration, and therefore 1338 * the elapsed fraction, of the animation. The return value indicates whether the animation 1339 * should be ended (which happens when the elapsed time of the animation exceeds the 1340 * animation's duration, including the repeatCount). 1341 * 1342 * @param currentTime The current time, as tracked by the static timing handler 1343 * @return true if the animation's duration, including any repetitions due to 1344 * <code>repeatCount</code>, has been exceeded and the animation should be ended. 1345 */ animationFrame(long currentTime)1346 boolean animationFrame(long currentTime) { 1347 boolean done = false; 1348 switch (mPlayingState) { 1349 case RUNNING: 1350 case SEEKED: 1351 float fraction = mDuration > 0 ? (float)(currentTime - mStartTime) / mDuration : 1f; 1352 if (mDuration == 0 && mRepeatCount != INFINITE) { 1353 // Skip to the end 1354 mCurrentIteration = mRepeatCount; 1355 if (!mReversing) { 1356 mPlayingBackwards = false; 1357 } 1358 } 1359 if (fraction >= 1f) { 1360 if (mCurrentIteration < mRepeatCount || mRepeatCount == INFINITE) { 1361 // Time to repeat 1362 if (mListeners != null) { 1363 int numListeners = mListeners.size(); 1364 for (int i = 0; i < numListeners; ++i) { 1365 mListeners.get(i).onAnimationRepeat(this); 1366 } 1367 } 1368 if (mRepeatMode == REVERSE) { 1369 mPlayingBackwards = !mPlayingBackwards; 1370 } 1371 mCurrentIteration += (int) fraction; 1372 fraction = fraction % 1f; 1373 mStartTime += mDuration; 1374 // Note: We do not need to update the value of mStartTimeCommitted here 1375 // since we just added a duration offset. 1376 } else { 1377 done = true; 1378 fraction = Math.min(fraction, 1.0f); 1379 } 1380 } 1381 if (mPlayingBackwards) { 1382 fraction = 1f - fraction; 1383 } 1384 animateValue(fraction); 1385 break; 1386 } 1387 1388 return done; 1389 } 1390 1391 /** 1392 * Processes a frame of the animation, adjusting the start time if needed. 1393 * 1394 * @param frameTime The frame time. 1395 * @return true if the animation has ended. 1396 */ doAnimationFrame(long frameTime)1397 final boolean doAnimationFrame(long frameTime) { 1398 if (mPlayingState == STOPPED) { 1399 mPlayingState = RUNNING; 1400 if (mSeekFraction < 0) { 1401 mStartTime = frameTime; 1402 } else { 1403 long seekTime = (long) (mDuration * mSeekFraction); 1404 mStartTime = frameTime - seekTime; 1405 mSeekFraction = -1; 1406 } 1407 mStartTimeCommitted = false; // allow start time to be compensated for jank 1408 } 1409 if (mPaused) { 1410 if (mPauseTime < 0) { 1411 mPauseTime = frameTime; 1412 } 1413 return false; 1414 } else if (mResumed) { 1415 mResumed = false; 1416 if (mPauseTime > 0) { 1417 // Offset by the duration that the animation was paused 1418 mStartTime += (frameTime - mPauseTime); 1419 mStartTimeCommitted = false; // allow start time to be compensated for jank 1420 } 1421 } 1422 // The frame time might be before the start time during the first frame of 1423 // an animation. The "current time" must always be on or after the start 1424 // time to avoid animating frames at negative time intervals. In practice, this 1425 // is very rare and only happens when seeking backwards. 1426 final long currentTime = Math.max(frameTime, mStartTime); 1427 return animationFrame(currentTime); 1428 } 1429 1430 /** 1431 * Returns the current animation fraction, which is the elapsed/interpolated fraction used in 1432 * the most recent frame update on the animation. 1433 * 1434 * @return Elapsed/interpolated fraction of the animation. 1435 */ getAnimatedFraction()1436 public float getAnimatedFraction() { 1437 return mCurrentFraction; 1438 } 1439 1440 /** 1441 * This method is called with the elapsed fraction of the animation during every 1442 * animation frame. This function turns the elapsed fraction into an interpolated fraction 1443 * and then into an animated value (from the evaluator. The function is called mostly during 1444 * animation updates, but it is also called when the <code>end()</code> 1445 * function is called, to set the final value on the property. 1446 * 1447 * <p>Overrides of this method must call the superclass to perform the calculation 1448 * of the animated value.</p> 1449 * 1450 * @param fraction The elapsed fraction of the animation. 1451 */ 1452 @CallSuper animateValue(float fraction)1453 void animateValue(float fraction) { 1454 fraction = mInterpolator.getInterpolation(fraction); 1455 mCurrentFraction = fraction; 1456 int numValues = mValues.length; 1457 for (int i = 0; i < numValues; ++i) { 1458 mValues[i].calculateValue(fraction); 1459 } 1460 if (mUpdateListeners != null) { 1461 int numListeners = mUpdateListeners.size(); 1462 for (int i = 0; i < numListeners; ++i) { 1463 mUpdateListeners.get(i).onAnimationUpdate(this); 1464 } 1465 } 1466 } 1467 1468 @Override clone()1469 public ValueAnimator clone() { 1470 final ValueAnimator anim = (ValueAnimator) super.clone(); 1471 if (mUpdateListeners != null) { 1472 anim.mUpdateListeners = new ArrayList<AnimatorUpdateListener>(mUpdateListeners); 1473 } 1474 anim.mSeekFraction = -1; 1475 anim.mPlayingBackwards = false; 1476 anim.mReversing = false; 1477 anim.mCurrentIteration = 0; 1478 anim.mInitialized = false; 1479 anim.mPlayingState = STOPPED; 1480 anim.mStartedDelay = false; 1481 anim.mStarted = false; 1482 anim.mRunning = false; 1483 anim.mPaused = false; 1484 anim.mResumed = false; 1485 anim.mStartListenersCalled = false; 1486 anim.mStartTime = 0; 1487 anim.mStartTimeCommitted = false; 1488 anim.mPauseTime = 0; 1489 anim.mCurrentFraction = 0; 1490 anim.mDelayStartTime = 0; 1491 1492 PropertyValuesHolder[] oldValues = mValues; 1493 if (oldValues != null) { 1494 int numValues = oldValues.length; 1495 anim.mValues = new PropertyValuesHolder[numValues]; 1496 anim.mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 1497 for (int i = 0; i < numValues; ++i) { 1498 PropertyValuesHolder newValuesHolder = oldValues[i].clone(); 1499 anim.mValues[i] = newValuesHolder; 1500 anim.mValuesMap.put(newValuesHolder.getPropertyName(), newValuesHolder); 1501 } 1502 } 1503 return anim; 1504 } 1505 1506 /** 1507 * Implementors of this interface can add themselves as update listeners 1508 * to an <code>ValueAnimator</code> instance to receive callbacks on every animation 1509 * frame, after the current frame's values have been calculated for that 1510 * <code>ValueAnimator</code>. 1511 */ 1512 public static interface AnimatorUpdateListener { 1513 /** 1514 * <p>Notifies the occurrence of another frame of the animation.</p> 1515 * 1516 * @param animation The animation which was repeated. 1517 */ onAnimationUpdate(ValueAnimator animation)1518 void onAnimationUpdate(ValueAnimator animation); 1519 1520 } 1521 1522 /** 1523 * Return the number of animations currently running. 1524 * 1525 * Used by StrictMode internally to annotate violations. 1526 * May be called on arbitrary threads! 1527 * 1528 * @hide 1529 */ getCurrentAnimationsCount()1530 public static int getCurrentAnimationsCount() { 1531 AnimationHandler handler = sAnimationHandler.get(); 1532 return handler != null ? handler.mAnimations.size() : 0; 1533 } 1534 1535 /** 1536 * Clear all animations on this thread, without canceling or ending them. 1537 * This should be used with caution. 1538 * 1539 * @hide 1540 */ clearAllAnimations()1541 public static void clearAllAnimations() { 1542 AnimationHandler handler = sAnimationHandler.get(); 1543 if (handler != null) { 1544 handler.mAnimations.clear(); 1545 handler.mPendingAnimations.clear(); 1546 handler.mDelayedAnims.clear(); 1547 } 1548 } 1549 getOrCreateAnimationHandler()1550 private static AnimationHandler getOrCreateAnimationHandler() { 1551 AnimationHandler handler = sAnimationHandler.get(); 1552 if (handler == null) { 1553 handler = new AnimationHandler(); 1554 sAnimationHandler.set(handler); 1555 } 1556 return handler; 1557 } 1558 1559 @Override toString()1560 public String toString() { 1561 String returnVal = "ValueAnimator@" + Integer.toHexString(hashCode()); 1562 if (mValues != null) { 1563 for (int i = 0; i < mValues.length; ++i) { 1564 returnVal += "\n " + mValues[i].toString(); 1565 } 1566 } 1567 return returnVal; 1568 } 1569 1570 /** 1571 * <p>Whether or not the ValueAnimator is allowed to run asynchronously off of 1572 * the UI thread. This is a hint that informs the ValueAnimator that it is 1573 * OK to run the animation off-thread, however ValueAnimator may decide 1574 * that it must run the animation on the UI thread anyway. For example if there 1575 * is an {@link AnimatorUpdateListener} the animation will run on the UI thread, 1576 * regardless of the value of this hint.</p> 1577 * 1578 * <p>Regardless of whether or not the animation runs asynchronously, all 1579 * listener callbacks will be called on the UI thread.</p> 1580 * 1581 * <p>To be able to use this hint the following must be true:</p> 1582 * <ol> 1583 * <li>{@link #getAnimatedFraction()} is not needed (it will return undefined values).</li> 1584 * <li>The animator is immutable while {@link #isStarted()} is true. Requests 1585 * to change values, duration, delay, etc... may be ignored.</li> 1586 * <li>Lifecycle callback events may be asynchronous. Events such as 1587 * {@link Animator.AnimatorListener#onAnimationEnd(Animator)} or 1588 * {@link Animator.AnimatorListener#onAnimationRepeat(Animator)} may end up delayed 1589 * as they must be posted back to the UI thread, and any actions performed 1590 * by those callbacks (such as starting new animations) will not happen 1591 * in the same frame.</li> 1592 * <li>State change requests ({@link #cancel()}, {@link #end()}, {@link #reverse()}, etc...) 1593 * may be asynchronous. It is guaranteed that all state changes that are 1594 * performed on the UI thread in the same frame will be applied as a single 1595 * atomic update, however that frame may be the current frame, 1596 * the next frame, or some future frame. This will also impact the observed 1597 * state of the Animator. For example, {@link #isStarted()} may still return true 1598 * after a call to {@link #end()}. Using the lifecycle callbacks is preferred over 1599 * queries to {@link #isStarted()}, {@link #isRunning()}, and {@link #isPaused()} 1600 * for this reason.</li> 1601 * </ol> 1602 * @hide 1603 */ 1604 @Override setAllowRunningAsynchronously(boolean mayRunAsync)1605 public void setAllowRunningAsynchronously(boolean mayRunAsync) { 1606 // It is up to subclasses to support this, if they can. 1607 } 1608 } 1609