ValueAnimator.java revision 61045c518b18a7cee30954fe45f9db8c14e705e1
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 17package android.animation; 18 19import android.annotation.CallSuper; 20import android.annotation.IntDef; 21import android.os.Looper; 22import android.os.Trace; 23import android.util.AndroidRuntimeException; 24import android.util.Log; 25import android.view.animation.AccelerateDecelerateInterpolator; 26import android.view.animation.AnimationUtils; 27import android.view.animation.LinearInterpolator; 28 29import java.lang.annotation.Retention; 30import java.lang.annotation.RetentionPolicy; 31import java.util.ArrayList; 32import java.util.HashMap; 33 34/** 35 * This class provides a simple timing engine for running animations 36 * which calculate animated values and set them on target objects. 37 * 38 * <p>There is a single timing pulse that all animations use. It runs in a 39 * custom handler to ensure that property changes happen on the UI thread.</p> 40 * 41 * <p>By default, ValueAnimator uses non-linear time interpolation, via the 42 * {@link AccelerateDecelerateInterpolator} class, which accelerates into and decelerates 43 * out of an animation. This behavior can be changed by calling 44 * {@link ValueAnimator#setInterpolator(TimeInterpolator)}.</p> 45 * 46 * <p>Animators can be created from either code or resource files. Here is an example 47 * of a ValueAnimator resource file:</p> 48 * 49 * {@sample development/samples/ApiDemos/res/anim/animator.xml ValueAnimatorResources} 50 * 51 * <p>It is also possible to use a combination of {@link PropertyValuesHolder} and 52 * {@link Keyframe} resource tags to create a multi-step animation. 53 * Note that you can specify explicit fractional values (from 0 to 1) for 54 * each keyframe to determine when, in the overall duration, the animation should arrive at that 55 * value. Alternatively, you can leave the fractions off and the keyframes will be equally 56 * distributed within the total duration:</p> 57 * 58 * {@sample development/samples/ApiDemos/res/anim/value_animator_pvh_kf.xml 59 * ValueAnimatorKeyframeResources} 60 * 61 * <div class="special reference"> 62 * <h3>Developer Guides</h3> 63 * <p>For more information about animating with {@code ValueAnimator}, read the 64 * <a href="{@docRoot}guide/topics/graphics/prop-animation.html#value-animator">Property 65 * Animation</a> developer guide.</p> 66 * </div> 67 */ 68@SuppressWarnings("unchecked") 69public class ValueAnimator extends Animator implements AnimationHandler.AnimationFrameCallback { 70 private static final String TAG = "ValueAnimator"; 71 private static final boolean DEBUG = false; 72 73 /** 74 * Internal constants 75 */ 76 private static float sDurationScale = 1.0f; 77 78 /** 79 * Internal variables 80 * NOTE: This object implements the clone() method, making a deep copy of any referenced 81 * objects. As other non-trivial fields are added to this class, make sure to add logic 82 * to clone() to make deep copies of them. 83 */ 84 85 /** 86 * The first time that the animation's animateFrame() method is called. This time is used to 87 * determine elapsed time (and therefore the elapsed fraction) in subsequent calls 88 * to animateFrame(). 89 * 90 * Whenever mStartTime is set, you must also update mStartTimeCommitted. 91 */ 92 long mStartTime; 93 94 /** 95 * When true, the start time has been firmly committed as a chosen reference point in 96 * time by which the progress of the animation will be evaluated. When false, the 97 * start time may be updated when the first animation frame is committed so as 98 * to compensate for jank that may have occurred between when the start time was 99 * initialized and when the frame was actually drawn. 100 * 101 * This flag is generally set to false during the first frame of the animation 102 * when the animation playing state transitions from STOPPED to RUNNING or 103 * resumes after having been paused. This flag is set to true when the start time 104 * is firmly committed and should not be further compensated for jank. 105 */ 106 boolean mStartTimeCommitted; 107 108 /** 109 * Set when setCurrentPlayTime() is called. If negative, animation is not currently seeked 110 * to a value. 111 */ 112 float mSeekFraction = -1; 113 114 /** 115 * Set on the next frame after pause() is called, used to calculate a new startTime 116 * or delayStartTime which allows the animator to continue from the point at which 117 * it was paused. If negative, has not yet been set. 118 */ 119 private long mPauseTime; 120 121 /** 122 * Set when an animator is resumed. This triggers logic in the next frame which 123 * actually resumes the animator. 124 */ 125 private boolean mResumed = false; 126 127 // The time interpolator to be used if none is set on the animation 128 private static final TimeInterpolator sDefaultInterpolator = 129 new AccelerateDecelerateInterpolator(); 130 131 /** 132 * Flag to indicate whether this animator is playing in reverse mode, specifically 133 * by being started or interrupted by a call to reverse(). This flag is different than 134 * mPlayingBackwards, which indicates merely whether the current iteration of the 135 * animator is playing in reverse. It is used in corner cases to determine proper end 136 * behavior. 137 */ 138 private boolean mReversing; 139 140 /** 141 * Tracks the overall fraction of the animation, ranging from 0 to mRepeatCount + 1 142 */ 143 private float mOverallFraction = 0f; 144 145 /** 146 * Tracks current elapsed/eased fraction, for querying in getAnimatedFraction(). 147 * This is calculated by interpolating the fraction (range: [0, 1]) in the current iteration. 148 */ 149 private float mCurrentFraction = 0f; 150 151 /** 152 * Tracks the time (in milliseconds) when the last frame arrived. 153 */ 154 private long mLastFrameTime = 0; 155 156 /** 157 * Additional playing state to indicate whether an animator has been start()'d. There is 158 * some lag between a call to start() and the first animation frame. We should still note 159 * that the animation has been started, even if it's first animation frame has not yet 160 * happened, and reflect that state in isRunning(). 161 * Note that delayed animations are different: they are not started until their first 162 * animation frame, which occurs after their delay elapses. 163 */ 164 private boolean mRunning = false; 165 166 /** 167 * Additional playing state to indicate whether an animator has been start()'d, whether or 168 * not there is a nonzero startDelay. 169 */ 170 private boolean mStarted = false; 171 172 /** 173 * Tracks whether we've notified listeners of the onAnimationStart() event. This can be 174 * complex to keep track of since we notify listeners at different times depending on 175 * startDelay and whether start() was called before end(). 176 */ 177 private boolean mStartListenersCalled = false; 178 179 /** 180 * Flag that denotes whether the animation is set up and ready to go. Used to 181 * set up animation that has not yet been started. 182 */ 183 boolean mInitialized = false; 184 185 /** 186 * Flag that tracks whether animation has been requested to end. 187 */ 188 private boolean mAnimationEndRequested = false; 189 190 // 191 // Backing variables 192 // 193 194 // How long the animation should last in ms 195 private long mDuration = 300; 196 197 // The amount of time in ms to delay starting the animation after start() is called. Note 198 // that this start delay is unscaled. When there is a duration scale set on the animator, the 199 // scaling factor will be applied to this delay. 200 private long mStartDelay = 0; 201 202 // The number of times the animation will repeat. The default is 0, which means the animation 203 // will play only once 204 private int mRepeatCount = 0; 205 206 /** 207 * The type of repetition that will occur when repeatMode is nonzero. RESTART means the 208 * animation will start from the beginning on every new cycle. REVERSE means the animation 209 * will reverse directions on each iteration. 210 */ 211 private int mRepeatMode = RESTART; 212 213 /** 214 * The time interpolator to be used. The elapsed fraction of the animation will be passed 215 * through this interpolator to calculate the interpolated fraction, which is then used to 216 * calculate the animated values. 217 */ 218 private TimeInterpolator mInterpolator = sDefaultInterpolator; 219 220 /** 221 * The set of listeners to be sent events through the life of an animation. 222 */ 223 ArrayList<AnimatorUpdateListener> mUpdateListeners = null; 224 225 /** 226 * The property/value sets being animated. 227 */ 228 PropertyValuesHolder[] mValues; 229 230 /** 231 * A hashmap of the PropertyValuesHolder objects. This map is used to lookup animated values 232 * by property name during calls to getAnimatedValue(String). 233 */ 234 HashMap<String, PropertyValuesHolder> mValuesMap; 235 236 /** 237 * Public constants 238 */ 239 240 /** @hide */ 241 @IntDef({RESTART, REVERSE}) 242 @Retention(RetentionPolicy.SOURCE) 243 public @interface RepeatMode {} 244 245 /** 246 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 247 * or a positive value, the animation restarts from the beginning. 248 */ 249 public static final int RESTART = 1; 250 /** 251 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 252 * or a positive value, the animation reverses direction on every iteration. 253 */ 254 public static final int REVERSE = 2; 255 /** 256 * This value used used with the {@link #setRepeatCount(int)} property to repeat 257 * the animation indefinitely. 258 */ 259 public static final int INFINITE = -1; 260 261 /** 262 * @hide 263 */ 264 public static void setDurationScale(float durationScale) { 265 sDurationScale = durationScale; 266 } 267 268 /** 269 * @hide 270 */ 271 public static float getDurationScale() { 272 return sDurationScale; 273 } 274 275 /** 276 * Creates a new ValueAnimator object. This default constructor is primarily for 277 * use internally; the factory methods which take parameters are more generally 278 * useful. 279 */ 280 public ValueAnimator() { 281 } 282 283 /** 284 * Constructs and returns a ValueAnimator that animates between int values. A single 285 * value implies that that value is the one being animated to. However, this is not typically 286 * useful in a ValueAnimator object because there is no way for the object to determine the 287 * starting value for the animation (unlike ObjectAnimator, which can derive that value 288 * from the target object and property being animated). Therefore, there should typically 289 * be two or more values. 290 * 291 * @param values A set of values that the animation will animate between over time. 292 * @return A ValueAnimator object that is set up to animate between the given values. 293 */ 294 public static ValueAnimator ofInt(int... values) { 295 ValueAnimator anim = new ValueAnimator(); 296 anim.setIntValues(values); 297 return anim; 298 } 299 300 /** 301 * Constructs and returns a ValueAnimator that animates between color values. A single 302 * value implies that that value is the one being animated to. However, this is not typically 303 * useful in a ValueAnimator object because there is no way for the object to determine the 304 * starting value for the animation (unlike ObjectAnimator, which can derive that value 305 * from the target object and property being animated). Therefore, there should typically 306 * be two or more values. 307 * 308 * @param values A set of values that the animation will animate between over time. 309 * @return A ValueAnimator object that is set up to animate between the given values. 310 */ 311 public static ValueAnimator ofArgb(int... values) { 312 ValueAnimator anim = new ValueAnimator(); 313 anim.setIntValues(values); 314 anim.setEvaluator(ArgbEvaluator.getInstance()); 315 return anim; 316 } 317 318 /** 319 * Constructs and returns a ValueAnimator that animates between float values. A single 320 * value implies that that value is the one being animated to. However, this is not typically 321 * useful in a ValueAnimator object because there is no way for the object to determine the 322 * starting value for the animation (unlike ObjectAnimator, which can derive that value 323 * from the target object and property being animated). Therefore, there should typically 324 * be two or more values. 325 * 326 * @param values A set of values that the animation will animate between over time. 327 * @return A ValueAnimator object that is set up to animate between the given values. 328 */ 329 public static ValueAnimator ofFloat(float... values) { 330 ValueAnimator anim = new ValueAnimator(); 331 anim.setFloatValues(values); 332 return anim; 333 } 334 335 /** 336 * Constructs and returns a ValueAnimator that animates between the values 337 * specified in the PropertyValuesHolder objects. 338 * 339 * @param values A set of PropertyValuesHolder objects whose values will be animated 340 * between over time. 341 * @return A ValueAnimator object that is set up to animate between the given values. 342 */ 343 public static ValueAnimator ofPropertyValuesHolder(PropertyValuesHolder... values) { 344 ValueAnimator anim = new ValueAnimator(); 345 anim.setValues(values); 346 return anim; 347 } 348 /** 349 * Constructs and returns a ValueAnimator that animates between Object values. A single 350 * value implies that that value is the one being animated to. However, this is not typically 351 * useful in a ValueAnimator object because there is no way for the object to determine the 352 * starting value for the animation (unlike ObjectAnimator, which can derive that value 353 * from the target object and property being animated). Therefore, there should typically 354 * be two or more values. 355 * 356 * <p><strong>Note:</strong> The Object values are stored as references to the original 357 * objects, which means that changes to those objects after this method is called will 358 * affect the values on the animator. If the objects will be mutated externally after 359 * this method is called, callers should pass a copy of those objects instead. 360 * 361 * <p>Since ValueAnimator does not know how to animate between arbitrary Objects, this 362 * factory method also takes a TypeEvaluator object that the ValueAnimator will use 363 * to perform that interpolation. 364 * 365 * @param evaluator A TypeEvaluator that will be called on each animation frame to 366 * provide the ncessry interpolation between the Object values to derive the animated 367 * value. 368 * @param values A set of values that the animation will animate between over time. 369 * @return A ValueAnimator object that is set up to animate between the given values. 370 */ 371 public static ValueAnimator ofObject(TypeEvaluator evaluator, Object... values) { 372 ValueAnimator anim = new ValueAnimator(); 373 anim.setObjectValues(values); 374 anim.setEvaluator(evaluator); 375 return anim; 376 } 377 378 /** 379 * Sets int values that will be animated between. A single 380 * value implies that that value is the one being animated to. However, this is not typically 381 * useful in a ValueAnimator object because there is no way for the object to determine the 382 * starting value for the animation (unlike ObjectAnimator, which can derive that value 383 * from the target object and property being animated). Therefore, there should typically 384 * be two or more values. 385 * 386 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 387 * than one PropertyValuesHolder object, this method will set the values for the first 388 * of those objects.</p> 389 * 390 * @param values A set of values that the animation will animate between over time. 391 */ 392 public void setIntValues(int... values) { 393 if (values == null || values.length == 0) { 394 return; 395 } 396 if (mValues == null || mValues.length == 0) { 397 setValues(PropertyValuesHolder.ofInt("", values)); 398 } else { 399 PropertyValuesHolder valuesHolder = mValues[0]; 400 valuesHolder.setIntValues(values); 401 } 402 // New property/values/target should cause re-initialization prior to starting 403 mInitialized = false; 404 } 405 406 /** 407 * Sets float values that will be animated between. A single 408 * value implies that that value is the one being animated to. However, this is not typically 409 * useful in a ValueAnimator object because there is no way for the object to determine the 410 * starting value for the animation (unlike ObjectAnimator, which can derive that value 411 * from the target object and property being animated). Therefore, there should typically 412 * be two or more values. 413 * 414 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 415 * than one PropertyValuesHolder object, this method will set the values for the first 416 * of those objects.</p> 417 * 418 * @param values A set of values that the animation will animate between over time. 419 */ 420 public void setFloatValues(float... values) { 421 if (values == null || values.length == 0) { 422 return; 423 } 424 if (mValues == null || mValues.length == 0) { 425 setValues(PropertyValuesHolder.ofFloat("", values)); 426 } else { 427 PropertyValuesHolder valuesHolder = mValues[0]; 428 valuesHolder.setFloatValues(values); 429 } 430 // New property/values/target should cause re-initialization prior to starting 431 mInitialized = false; 432 } 433 434 /** 435 * Sets the values to animate between for this animation. A single 436 * value implies that that value is the one being animated to. However, this is not typically 437 * useful in a ValueAnimator object because there is no way for the object to determine the 438 * starting value for the animation (unlike ObjectAnimator, which can derive that value 439 * from the target object and property being animated). Therefore, there should typically 440 * be two or more values. 441 * 442 * <p><strong>Note:</strong> The Object values are stored as references to the original 443 * objects, which means that changes to those objects after this method is called will 444 * affect the values on the animator. If the objects will be mutated externally after 445 * this method is called, callers should pass a copy of those objects instead. 446 * 447 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 448 * than one PropertyValuesHolder object, this method will set the values for the first 449 * of those objects.</p> 450 * 451 * <p>There should be a TypeEvaluator set on the ValueAnimator that knows how to interpolate 452 * between these value objects. ValueAnimator only knows how to interpolate between the 453 * primitive types specified in the other setValues() methods.</p> 454 * 455 * @param values The set of values to animate between. 456 */ 457 public void setObjectValues(Object... values) { 458 if (values == null || values.length == 0) { 459 return; 460 } 461 if (mValues == null || mValues.length == 0) { 462 setValues(PropertyValuesHolder.ofObject("", null, values)); 463 } else { 464 PropertyValuesHolder valuesHolder = mValues[0]; 465 valuesHolder.setObjectValues(values); 466 } 467 // New property/values/target should cause re-initialization prior to starting 468 mInitialized = false; 469 } 470 471 /** 472 * Sets the values, per property, being animated between. This function is called internally 473 * by the constructors of ValueAnimator that take a list of values. But a ValueAnimator can 474 * be constructed without values and this method can be called to set the values manually 475 * instead. 476 * 477 * @param values The set of values, per property, being animated between. 478 */ 479 public void setValues(PropertyValuesHolder... values) { 480 int numValues = values.length; 481 mValues = values; 482 mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 483 for (int i = 0; i < numValues; ++i) { 484 PropertyValuesHolder valuesHolder = values[i]; 485 mValuesMap.put(valuesHolder.getPropertyName(), valuesHolder); 486 } 487 // New property/values/target should cause re-initialization prior to starting 488 mInitialized = false; 489 } 490 491 /** 492 * Returns the values that this ValueAnimator animates between. These values are stored in 493 * PropertyValuesHolder objects, even if the ValueAnimator was created with a simple list 494 * of value objects instead. 495 * 496 * @return PropertyValuesHolder[] An array of PropertyValuesHolder objects which hold the 497 * values, per property, that define the animation. 498 */ 499 public PropertyValuesHolder[] getValues() { 500 return mValues; 501 } 502 503 /** 504 * This function is called immediately before processing the first animation 505 * frame of an animation. If there is a nonzero <code>startDelay</code>, the 506 * function is called after that delay ends. 507 * It takes care of the final initialization steps for the 508 * animation. 509 * 510 * <p>Overrides of this method should call the superclass method to ensure 511 * that internal mechanisms for the animation are set up correctly.</p> 512 */ 513 @CallSuper 514 void initAnimation() { 515 if (!mInitialized) { 516 int numValues = mValues.length; 517 for (int i = 0; i < numValues; ++i) { 518 mValues[i].init(); 519 } 520 mInitialized = true; 521 } 522 } 523 524 /** 525 * Sets the length of the animation. The default duration is 300 milliseconds. 526 * 527 * @param duration The length of the animation, in milliseconds. This value cannot 528 * be negative. 529 * @return ValueAnimator The object called with setDuration(). This return 530 * value makes it easier to compose statements together that construct and then set the 531 * duration, as in <code>ValueAnimator.ofInt(0, 10).setDuration(500).start()</code>. 532 */ 533 @Override 534 public ValueAnimator setDuration(long duration) { 535 if (duration < 0) { 536 throw new IllegalArgumentException("Animators cannot have negative duration: " + 537 duration); 538 } 539 mDuration = duration; 540 return this; 541 } 542 543 private long getScaledDuration() { 544 return (long)(mDuration * sDurationScale); 545 } 546 547 /** 548 * Gets the length of the animation. The default duration is 300 milliseconds. 549 * 550 * @return The length of the animation, in milliseconds. 551 */ 552 @Override 553 public long getDuration() { 554 return mDuration; 555 } 556 557 @Override 558 public long getTotalDuration() { 559 if (mRepeatCount == INFINITE) { 560 return DURATION_INFINITE; 561 } else { 562 return mStartDelay + (mDuration * (mRepeatCount + 1)); 563 } 564 } 565 566 /** 567 * Sets the position of the animation to the specified point in time. This time should 568 * be between 0 and the total duration of the animation, including any repetition. If 569 * the animation has not yet been started, then it will not advance forward after it is 570 * set to this time; it will simply set the time to this value and perform any appropriate 571 * actions based on that time. If the animation is already running, then setCurrentPlayTime() 572 * will set the current playing time to this value and continue playing from that point. 573 * 574 * @param playTime The time, in milliseconds, to which the animation is advanced or rewound. 575 */ 576 public void setCurrentPlayTime(long playTime) { 577 float fraction = mDuration > 0 ? (float) playTime / mDuration : 1; 578 setCurrentFraction(fraction); 579 } 580 581 /** 582 * Sets the position of the animation to the specified fraction. This fraction should 583 * be between 0 and the total fraction of the animation, including any repetition. That is, 584 * a fraction of 0 will position the animation at the beginning, a value of 1 at the end, 585 * and a value of 2 at the end of a reversing animator that repeats once. If 586 * the animation has not yet been started, then it will not advance forward after it is 587 * set to this fraction; it will simply set the fraction to this value and perform any 588 * appropriate actions based on that fraction. If the animation is already running, then 589 * setCurrentFraction() will set the current fraction to this value and continue 590 * playing from that point. {@link Animator.AnimatorListener} events are not called 591 * due to changing the fraction; those events are only processed while the animation 592 * is running. 593 * 594 * @param fraction The fraction to which the animation is advanced or rewound. Values 595 * outside the range of 0 to the maximum fraction for the animator will be clamped to 596 * the correct range. 597 */ 598 public void setCurrentFraction(float fraction) { 599 initAnimation(); 600 fraction = clampFraction(fraction); 601 long seekTime = (long) (getScaledDuration() * fraction); 602 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 603 mStartTime = currentTime - seekTime; 604 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 605 if (!mRunning) { 606 mSeekFraction = fraction; 607 } 608 mOverallFraction = fraction; 609 final float currentIterationFraction = getCurrentIterationFraction(fraction); 610 animateValue(currentIterationFraction); 611 } 612 613 /** 614 * Calculates current iteration based on the overall fraction. The overall fraction will be 615 * in the range of [0, mRepeatCount + 1]. Both current iteration and fraction in the current 616 * iteration can be derived from it. 617 */ 618 private int getCurrentIteration(float fraction) { 619 fraction = clampFraction(fraction); 620 // If the overall fraction is a positive integer, we consider the current iteration to be 621 // complete. In other words, the fraction for the current iteration would be 1, and the 622 // current iteration would be overall fraction - 1. 623 double iteration = Math.floor(fraction); 624 if (fraction == iteration && fraction > 0) { 625 iteration--; 626 } 627 return (int) iteration; 628 } 629 630 /** 631 * Calculates the fraction of the current iteration, taking into account whether the animation 632 * should be played backwards. E.g. When the animation is played backwards in an iteration, 633 * the fraction for that iteration will go from 1f to 0f. 634 */ 635 private float getCurrentIterationFraction(float fraction) { 636 fraction = clampFraction(fraction); 637 int iteration = getCurrentIteration(fraction); 638 float currentFraction = fraction - iteration; 639 return shouldPlayBackward(iteration) ? 1f - currentFraction : currentFraction; 640 } 641 642 /** 643 * Clamps fraction into the correct range: [0, mRepeatCount + 1]. If repeat count is infinite, 644 * no upper bound will be set for the fraction. 645 * 646 * @param fraction fraction to be clamped 647 * @return fraction clamped into the range of [0, mRepeatCount + 1] 648 */ 649 private float clampFraction(float fraction) { 650 if (fraction < 0) { 651 fraction = 0; 652 } else if (mRepeatCount != INFINITE) { 653 fraction = Math.min(fraction, mRepeatCount + 1); 654 } 655 return fraction; 656 } 657 658 /** 659 * Calculates the direction of animation playing (i.e. forward or backward), based on 1) 660 * whether the entire animation is being reversed, 2) repeat mode applied to the current 661 * iteration. 662 */ 663 private boolean shouldPlayBackward(int iteration) { 664 if (iteration > 0 && mRepeatMode == REVERSE && 665 (iteration < (mRepeatCount + 1) || mRepeatCount == INFINITE)) { 666 // if we were seeked to some other iteration in a reversing animator, 667 // figure out the correct direction to start playing based on the iteration 668 if (mReversing) { 669 return (iteration % 2) == 0; 670 } else { 671 return (iteration % 2) != 0; 672 } 673 } else { 674 return mReversing; 675 } 676 } 677 678 /** 679 * Gets the current position of the animation in time, which is equal to the current 680 * time minus the time that the animation started. An animation that is not yet started will 681 * return a value of zero, unless the animation has has its play time set via 682 * {@link #setCurrentPlayTime(long)} or {@link #setCurrentFraction(float)}, in which case 683 * it will return the time that was set. 684 * 685 * @return The current position in time of the animation. 686 */ 687 public long getCurrentPlayTime() { 688 if (!mInitialized || (!mStarted && mSeekFraction < 0)) { 689 return 0; 690 } 691 if (mSeekFraction >= 0) { 692 return (long) (mDuration * mSeekFraction); 693 } 694 float durationScale = sDurationScale == 0 ? 1 : sDurationScale; 695 return (long) ((AnimationUtils.currentAnimationTimeMillis() - mStartTime) / durationScale); 696 } 697 698 /** 699 * The amount of time, in milliseconds, to delay starting the animation after 700 * {@link #start()} is called. 701 * 702 * @return the number of milliseconds to delay running the animation 703 */ 704 @Override 705 public long getStartDelay() { 706 return mStartDelay; 707 } 708 709 /** 710 * The amount of time, in milliseconds, to delay starting the animation after 711 * {@link #start()} is called. Note that the start delay should always be non-negative. Any 712 * negative start delay will be clamped to 0 on N and above. 713 * 714 * @param startDelay The amount of the delay, in milliseconds 715 */ 716 @Override 717 public void setStartDelay(long startDelay) { 718 // Clamp start delay to non-negative range. 719 if (startDelay < 0) { 720 Log.w(TAG, "Start delay should always be non-negative"); 721 startDelay = 0; 722 } 723 mStartDelay = startDelay; 724 } 725 726 /** 727 * The amount of time, in milliseconds, between each frame of the animation. This is a 728 * requested time that the animation will attempt to honor, but the actual delay between 729 * frames may be different, depending on system load and capabilities. This is a static 730 * function because the same delay will be applied to all animations, since they are all 731 * run off of a single timing loop. 732 * 733 * The frame delay may be ignored when the animation system uses an external timing 734 * source, such as the display refresh rate (vsync), to govern animations. 735 * 736 * Note that this method should be called from the same thread that {@link #start()} is 737 * called in order to check the frame delay for that animation. A runtime exception will be 738 * thrown if the calling thread does not have a Looper. 739 * 740 * @return the requested time between frames, in milliseconds 741 */ 742 public static long getFrameDelay() { 743 return AnimationHandler.getInstance().getFrameDelay(); 744 } 745 746 /** 747 * The amount of time, in milliseconds, between each frame of the animation. This is a 748 * requested time that the animation will attempt to honor, but the actual delay between 749 * frames may be different, depending on system load and capabilities. This is a static 750 * function because the same delay will be applied to all animations, since they are all 751 * run off of a single timing loop. 752 * 753 * The frame delay may be ignored when the animation system uses an external timing 754 * source, such as the display refresh rate (vsync), to govern animations. 755 * 756 * Note that this method should be called from the same thread that {@link #start()} is 757 * called in order to have the new frame delay take effect on that animation. A runtime 758 * exception will be thrown if the calling thread does not have a Looper. 759 * 760 * @param frameDelay the requested time between frames, in milliseconds 761 */ 762 public static void setFrameDelay(long frameDelay) { 763 AnimationHandler.getInstance().setFrameDelay(frameDelay); 764 } 765 766 /** 767 * The most recent value calculated by this <code>ValueAnimator</code> when there is just one 768 * property being animated. This value is only sensible while the animation is running. The main 769 * purpose for this read-only property is to retrieve the value from the <code>ValueAnimator</code> 770 * during a call to {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 771 * is called during each animation frame, immediately after the value is calculated. 772 * 773 * @return animatedValue The value most recently calculated by this <code>ValueAnimator</code> for 774 * the single property being animated. If there are several properties being animated 775 * (specified by several PropertyValuesHolder objects in the constructor), this function 776 * returns the animated value for the first of those objects. 777 */ 778 public Object getAnimatedValue() { 779 if (mValues != null && mValues.length > 0) { 780 return mValues[0].getAnimatedValue(); 781 } 782 // Shouldn't get here; should always have values unless ValueAnimator was set up wrong 783 return null; 784 } 785 786 /** 787 * The most recent value calculated by this <code>ValueAnimator</code> for <code>propertyName</code>. 788 * The main purpose for this read-only property is to retrieve the value from the 789 * <code>ValueAnimator</code> during a call to 790 * {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 791 * is called during each animation frame, immediately after the value is calculated. 792 * 793 * @return animatedValue The value most recently calculated for the named property 794 * by this <code>ValueAnimator</code>. 795 */ 796 public Object getAnimatedValue(String propertyName) { 797 PropertyValuesHolder valuesHolder = mValuesMap.get(propertyName); 798 if (valuesHolder != null) { 799 return valuesHolder.getAnimatedValue(); 800 } else { 801 // At least avoid crashing if called with bogus propertyName 802 return null; 803 } 804 } 805 806 /** 807 * Sets how many times the animation should be repeated. If the repeat 808 * count is 0, the animation is never repeated. If the repeat count is 809 * greater than 0 or {@link #INFINITE}, the repeat mode will be taken 810 * into account. The repeat count is 0 by default. 811 * 812 * @param value the number of times the animation should be repeated 813 */ 814 public void setRepeatCount(int value) { 815 mRepeatCount = value; 816 } 817 /** 818 * Defines how many times the animation should repeat. The default value 819 * is 0. 820 * 821 * @return the number of times the animation should repeat, or {@link #INFINITE} 822 */ 823 public int getRepeatCount() { 824 return mRepeatCount; 825 } 826 827 /** 828 * Defines what this animation should do when it reaches the end. This 829 * setting is applied only when the repeat count is either greater than 830 * 0 or {@link #INFINITE}. Defaults to {@link #RESTART}. 831 * 832 * @param value {@link #RESTART} or {@link #REVERSE} 833 */ 834 public void setRepeatMode(@RepeatMode int value) { 835 mRepeatMode = value; 836 } 837 838 /** 839 * Defines what this animation should do when it reaches the end. 840 * 841 * @return either one of {@link #REVERSE} or {@link #RESTART} 842 */ 843 @RepeatMode 844 public int getRepeatMode() { 845 return mRepeatMode; 846 } 847 848 /** 849 * Adds a listener to the set of listeners that are sent update events through the life of 850 * an animation. This method is called on all listeners for every frame of the animation, 851 * after the values for the animation have been calculated. 852 * 853 * @param listener the listener to be added to the current set of listeners for this animation. 854 */ 855 public void addUpdateListener(AnimatorUpdateListener listener) { 856 if (mUpdateListeners == null) { 857 mUpdateListeners = new ArrayList<AnimatorUpdateListener>(); 858 } 859 mUpdateListeners.add(listener); 860 } 861 862 /** 863 * Removes all listeners from the set listening to frame updates for this animation. 864 */ 865 public void removeAllUpdateListeners() { 866 if (mUpdateListeners == null) { 867 return; 868 } 869 mUpdateListeners.clear(); 870 mUpdateListeners = null; 871 } 872 873 /** 874 * Removes a listener from the set listening to frame updates for this animation. 875 * 876 * @param listener the listener to be removed from the current set of update listeners 877 * for this animation. 878 */ 879 public void removeUpdateListener(AnimatorUpdateListener listener) { 880 if (mUpdateListeners == null) { 881 return; 882 } 883 mUpdateListeners.remove(listener); 884 if (mUpdateListeners.size() == 0) { 885 mUpdateListeners = null; 886 } 887 } 888 889 890 /** 891 * The time interpolator used in calculating the elapsed fraction of this animation. The 892 * interpolator determines whether the animation runs with linear or non-linear motion, 893 * such as acceleration and deceleration. The default value is 894 * {@link android.view.animation.AccelerateDecelerateInterpolator} 895 * 896 * @param value the interpolator to be used by this animation. A value of <code>null</code> 897 * will result in linear interpolation. 898 */ 899 @Override 900 public void setInterpolator(TimeInterpolator value) { 901 if (value != null) { 902 mInterpolator = value; 903 } else { 904 mInterpolator = new LinearInterpolator(); 905 } 906 } 907 908 /** 909 * Returns the timing interpolator that this ValueAnimator uses. 910 * 911 * @return The timing interpolator for this ValueAnimator. 912 */ 913 @Override 914 public TimeInterpolator getInterpolator() { 915 return mInterpolator; 916 } 917 918 /** 919 * The type evaluator to be used when calculating the animated values of this animation. 920 * The system will automatically assign a float or int evaluator based on the type 921 * of <code>startValue</code> and <code>endValue</code> in the constructor. But if these values 922 * are not one of these primitive types, or if different evaluation is desired (such as is 923 * necessary with int values that represent colors), a custom evaluator needs to be assigned. 924 * For example, when running an animation on color values, the {@link ArgbEvaluator} 925 * should be used to get correct RGB color interpolation. 926 * 927 * <p>If this ValueAnimator has only one set of values being animated between, this evaluator 928 * will be used for that set. If there are several sets of values being animated, which is 929 * the case if PropertyValuesHolder objects were set on the ValueAnimator, then the evaluator 930 * is assigned just to the first PropertyValuesHolder object.</p> 931 * 932 * @param value the evaluator to be used this animation 933 */ 934 public void setEvaluator(TypeEvaluator value) { 935 if (value != null && mValues != null && mValues.length > 0) { 936 mValues[0].setEvaluator(value); 937 } 938 } 939 940 private void notifyStartListeners() { 941 if (mListeners != null && !mStartListenersCalled) { 942 ArrayList<AnimatorListener> tmpListeners = 943 (ArrayList<AnimatorListener>) mListeners.clone(); 944 int numListeners = tmpListeners.size(); 945 for (int i = 0; i < numListeners; ++i) { 946 tmpListeners.get(i).onAnimationStart(this); 947 } 948 } 949 mStartListenersCalled = true; 950 } 951 952 /** 953 * Start the animation playing. This version of start() takes a boolean flag that indicates 954 * whether the animation should play in reverse. The flag is usually false, but may be set 955 * to true if called from the reverse() method. 956 * 957 * <p>The animation started by calling this method will be run on the thread that called 958 * this method. This thread should have a Looper on it (a runtime exception will be thrown if 959 * this is not the case). Also, if the animation will animate 960 * properties of objects in the view hierarchy, then the calling thread should be the UI 961 * thread for that view hierarchy.</p> 962 * 963 * @param playBackwards Whether the ValueAnimator should start playing in reverse. 964 */ 965 private void start(boolean playBackwards) { 966 if (Looper.myLooper() == null) { 967 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 968 } 969 mReversing = playBackwards; 970 // Special case: reversing from seek-to-0 should act as if not seeked at all. 971 if (playBackwards && mSeekFraction != -1 && mSeekFraction != 0) { 972 if (mRepeatCount == INFINITE) { 973 // Calculate the fraction of the current iteration. 974 float fraction = (float) (mSeekFraction - Math.floor(mSeekFraction)); 975 mSeekFraction = 1 - fraction; 976 } else { 977 mSeekFraction = 1 + mRepeatCount - mSeekFraction; 978 } 979 } 980 mStarted = true; 981 mPaused = false; 982 mRunning = false; 983 AnimationHandler animationHandler = AnimationHandler.getInstance(); 984 animationHandler.addAnimationFrameCallback(this, (long) (mStartDelay * sDurationScale)); 985 986 if (mStartDelay == 0 || mSeekFraction >= 0) { 987 // If there's no start delay, init the animation and notify start listeners right away 988 // to be consistent with the previous behavior. Otherwise, postpone this until the first 989 // frame after the start delay. 990 startAnimation(); 991 if (mSeekFraction == -1) { 992 // No seek, start at play time 0. Note that the reason we are not using fraction 0 993 // is because for animations with 0 duration, we want to be consistent with pre-N 994 // behavior: skip to the final value immediately. 995 setCurrentPlayTime(0); 996 } else { 997 setCurrentFraction(mSeekFraction); 998 } 999 } 1000 } 1001 1002 @Override 1003 public void start() { 1004 start(false); 1005 } 1006 1007 @Override 1008 public void cancel() { 1009 if (Looper.myLooper() == null) { 1010 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 1011 } 1012 1013 // If end has already been requested, through a previous end() or cancel() call, no-op 1014 // until animation starts again. 1015 if (mAnimationEndRequested) { 1016 return; 1017 } 1018 1019 // Only cancel if the animation is actually running or has been started and is about 1020 // to run 1021 // Only notify listeners if the animator has actually started 1022 if ((mStarted || mRunning) && mListeners != null) { 1023 if (!mRunning) { 1024 // If it's not yet running, then start listeners weren't called. Call them now. 1025 notifyStartListeners(); 1026 } 1027 ArrayList<AnimatorListener> tmpListeners = 1028 (ArrayList<AnimatorListener>) mListeners.clone(); 1029 for (AnimatorListener listener : tmpListeners) { 1030 listener.onAnimationCancel(this); 1031 } 1032 } 1033 endAnimation(); 1034 1035 } 1036 1037 @Override 1038 public void end() { 1039 if (Looper.myLooper() == null) { 1040 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 1041 } 1042 if (!mRunning) { 1043 // Special case if the animation has not yet started; get it ready for ending 1044 startAnimation(); 1045 mStarted = true; 1046 } else if (!mInitialized) { 1047 initAnimation(); 1048 } 1049 animateValue(shouldPlayBackward(mRepeatCount) ? 0f : 1f); 1050 endAnimation(); 1051 } 1052 1053 @Override 1054 public void resume() { 1055 if (Looper.myLooper() == null) { 1056 throw new AndroidRuntimeException("Animators may only be resumed from the same " + 1057 "thread that the animator was started on"); 1058 } 1059 if (mPaused && !mResumed) { 1060 mResumed = true; 1061 if (mPauseTime > 0) { 1062 AnimationHandler handler = AnimationHandler.getInstance(); 1063 handler.addAnimationFrameCallback(this, 0); 1064 } 1065 } 1066 super.resume(); 1067 } 1068 1069 @Override 1070 public void pause() { 1071 boolean previouslyPaused = mPaused; 1072 super.pause(); 1073 if (!previouslyPaused && mPaused) { 1074 mPauseTime = -1; 1075 mResumed = false; 1076 } 1077 } 1078 1079 @Override 1080 public boolean isRunning() { 1081 return mRunning; 1082 } 1083 1084 @Override 1085 public boolean isStarted() { 1086 return mStarted; 1087 } 1088 1089 /** 1090 * Plays the ValueAnimator in reverse. If the animation is already running, 1091 * it will stop itself and play backwards from the point reached when reverse was called. 1092 * If the animation is not currently running, then it will start from the end and 1093 * play backwards. This behavior is only set for the current animation; future playing 1094 * of the animation will use the default behavior of playing forward. 1095 */ 1096 @Override 1097 public void reverse() { 1098 if (mRunning) { 1099 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 1100 long currentPlayTime = currentTime - mStartTime; 1101 long timeLeft = getScaledDuration() - currentPlayTime; 1102 mStartTime = currentTime - timeLeft; 1103 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 1104 mReversing = !mReversing; 1105 } else if (mStarted) { 1106 end(); 1107 } else { 1108 start(true); 1109 } 1110 } 1111 1112 /** 1113 * @hide 1114 */ 1115 @Override 1116 public boolean canReverse() { 1117 return true; 1118 } 1119 1120 /** 1121 * Called internally to end an animation by removing it from the animations list. Must be 1122 * called on the UI thread. 1123 */ 1124 private void endAnimation() { 1125 if (mAnimationEndRequested) { 1126 return; 1127 } 1128 AnimationHandler handler = AnimationHandler.getInstance(); 1129 handler.removeCallback(this); 1130 1131 mAnimationEndRequested = true; 1132 mPaused = false; 1133 if ((mStarted || mRunning) && mListeners != null) { 1134 if (!mRunning) { 1135 // If it's not yet running, then start listeners weren't called. Call them now. 1136 notifyStartListeners(); 1137 } 1138 ArrayList<AnimatorListener> tmpListeners = 1139 (ArrayList<AnimatorListener>) mListeners.clone(); 1140 int numListeners = tmpListeners.size(); 1141 for (int i = 0; i < numListeners; ++i) { 1142 tmpListeners.get(i).onAnimationEnd(this); 1143 } 1144 } 1145 mRunning = false; 1146 mStarted = false; 1147 mStartListenersCalled = false; 1148 mReversing = false; 1149 mLastFrameTime = 0; 1150 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1151 Trace.asyncTraceEnd(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1152 System.identityHashCode(this)); 1153 } 1154 } 1155 1156 /** 1157 * Called internally to start an animation by adding it to the active animations list. Must be 1158 * called on the UI thread. 1159 */ 1160 private void startAnimation() { 1161 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1162 Trace.asyncTraceBegin(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1163 System.identityHashCode(this)); 1164 } 1165 1166 mAnimationEndRequested = false; 1167 initAnimation(); 1168 mRunning = true; 1169 if (mSeekFraction >= 0) { 1170 mOverallFraction = mSeekFraction; 1171 } else { 1172 mOverallFraction = 0f; 1173 } 1174 if (mListeners != null) { 1175 notifyStartListeners(); 1176 } 1177 } 1178 1179 /** 1180 * Returns the name of this animator for debugging purposes. 1181 */ 1182 String getNameForTrace() { 1183 return "animator"; 1184 } 1185 1186 /** 1187 * Applies an adjustment to the animation to compensate for jank between when 1188 * the animation first ran and when the frame was drawn. 1189 * @hide 1190 */ 1191 public void commitAnimationFrame(long frameTime) { 1192 if (!mStartTimeCommitted) { 1193 mStartTimeCommitted = true; 1194 long adjustment = frameTime - mLastFrameTime; 1195 if (adjustment > 0) { 1196 mStartTime += adjustment; 1197 if (DEBUG) { 1198 Log.d(TAG, "Adjusted start time by " + adjustment + " ms: " + toString()); 1199 } 1200 } 1201 } 1202 } 1203 1204 /** 1205 * This internal function processes a single animation frame for a given animation. The 1206 * currentTime parameter is the timing pulse sent by the handler, used to calculate the 1207 * elapsed duration, and therefore 1208 * the elapsed fraction, of the animation. The return value indicates whether the animation 1209 * should be ended (which happens when the elapsed time of the animation exceeds the 1210 * animation's duration, including the repeatCount). 1211 * 1212 * @param currentTime The current time, as tracked by the static timing handler 1213 * @return true if the animation's duration, including any repetitions due to 1214 * <code>repeatCount</code> has been exceeded and the animation should be ended. 1215 */ 1216 boolean animateBasedOnTime(long currentTime) { 1217 boolean done = false; 1218 if (mRunning) { 1219 final long scaledDuration = getScaledDuration(); 1220 final float fraction = scaledDuration > 0 ? 1221 (float)(currentTime - mStartTime) / scaledDuration : 1f; 1222 final float lastFraction = mOverallFraction; 1223 final boolean newIteration = (int) fraction > (int) lastFraction; 1224 final boolean lastIterationFinished = (fraction >= mRepeatCount + 1) && 1225 (mRepeatCount != INFINITE); 1226 if (scaledDuration == 0) { 1227 // 0 duration animator, ignore the repeat count and skip to the end 1228 done = true; 1229 } else if (newIteration && !lastIterationFinished) { 1230 // Time to repeat 1231 if (mListeners != null) { 1232 int numListeners = mListeners.size(); 1233 for (int i = 0; i < numListeners; ++i) { 1234 mListeners.get(i).onAnimationRepeat(this); 1235 } 1236 } 1237 } else if (lastIterationFinished) { 1238 done = true; 1239 } 1240 mOverallFraction = clampFraction(fraction); 1241 float currentIterationFraction = getCurrentIterationFraction(mOverallFraction); 1242 animateValue(currentIterationFraction); 1243 } 1244 return done; 1245 } 1246 1247 /** 1248 * Processes a frame of the animation, adjusting the start time if needed. 1249 * 1250 * @param frameTime The frame time. 1251 * @return true if the animation has ended. 1252 * @hide 1253 */ 1254 public final void doAnimationFrame(long frameTime) { 1255 AnimationHandler handler = AnimationHandler.getInstance(); 1256 if (mLastFrameTime == 0) { 1257 // First frame 1258 handler.addOneShotCommitCallback(this); 1259 if (mStartDelay > 0) { 1260 startAnimation(); 1261 } 1262 if (mSeekFraction < 0) { 1263 mStartTime = frameTime; 1264 } else { 1265 long seekTime = (long) (getScaledDuration() * mSeekFraction); 1266 mStartTime = frameTime - seekTime; 1267 mSeekFraction = -1; 1268 } 1269 mStartTimeCommitted = false; // allow start time to be compensated for jank 1270 } 1271 mLastFrameTime = frameTime; 1272 if (mPaused) { 1273 mPauseTime = frameTime; 1274 handler.removeCallback(this); 1275 return; 1276 } else if (mResumed) { 1277 mResumed = false; 1278 if (mPauseTime > 0) { 1279 // Offset by the duration that the animation was paused 1280 mStartTime += (frameTime - mPauseTime); 1281 mStartTimeCommitted = false; // allow start time to be compensated for jank 1282 } 1283 handler.addOneShotCommitCallback(this); 1284 } 1285 // The frame time might be before the start time during the first frame of 1286 // an animation. The "current time" must always be on or after the start 1287 // time to avoid animating frames at negative time intervals. In practice, this 1288 // is very rare and only happens when seeking backwards. 1289 final long currentTime = Math.max(frameTime, mStartTime); 1290 boolean finished = animateBasedOnTime(currentTime); 1291 1292 if (finished) { 1293 endAnimation(); 1294 } 1295 } 1296 1297 /** 1298 * Returns the current animation fraction, which is the elapsed/interpolated fraction used in 1299 * the most recent frame update on the animation. 1300 * 1301 * @return Elapsed/interpolated fraction of the animation. 1302 */ 1303 public float getAnimatedFraction() { 1304 return mCurrentFraction; 1305 } 1306 1307 /** 1308 * This method is called with the elapsed fraction of the animation during every 1309 * animation frame. This function turns the elapsed fraction into an interpolated fraction 1310 * and then into an animated value (from the evaluator. The function is called mostly during 1311 * animation updates, but it is also called when the <code>end()</code> 1312 * function is called, to set the final value on the property. 1313 * 1314 * <p>Overrides of this method must call the superclass to perform the calculation 1315 * of the animated value.</p> 1316 * 1317 * @param fraction The elapsed fraction of the animation. 1318 */ 1319 @CallSuper 1320 void animateValue(float fraction) { 1321 fraction = mInterpolator.getInterpolation(fraction); 1322 mCurrentFraction = fraction; 1323 int numValues = mValues.length; 1324 for (int i = 0; i < numValues; ++i) { 1325 mValues[i].calculateValue(fraction); 1326 } 1327 if (mUpdateListeners != null) { 1328 int numListeners = mUpdateListeners.size(); 1329 for (int i = 0; i < numListeners; ++i) { 1330 mUpdateListeners.get(i).onAnimationUpdate(this); 1331 } 1332 } 1333 } 1334 1335 @Override 1336 public ValueAnimator clone() { 1337 final ValueAnimator anim = (ValueAnimator) super.clone(); 1338 if (mUpdateListeners != null) { 1339 anim.mUpdateListeners = new ArrayList<AnimatorUpdateListener>(mUpdateListeners); 1340 } 1341 anim.mSeekFraction = -1; 1342 anim.mReversing = false; 1343 anim.mInitialized = false; 1344 anim.mStarted = false; 1345 anim.mRunning = false; 1346 anim.mPaused = false; 1347 anim.mResumed = false; 1348 anim.mStartListenersCalled = false; 1349 anim.mStartTime = 0; 1350 anim.mStartTimeCommitted = false; 1351 anim.mAnimationEndRequested = false; 1352 anim.mPauseTime = 0; 1353 anim.mLastFrameTime = 0; 1354 anim.mOverallFraction = 0; 1355 anim.mCurrentFraction = 0; 1356 1357 PropertyValuesHolder[] oldValues = mValues; 1358 if (oldValues != null) { 1359 int numValues = oldValues.length; 1360 anim.mValues = new PropertyValuesHolder[numValues]; 1361 anim.mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 1362 for (int i = 0; i < numValues; ++i) { 1363 PropertyValuesHolder newValuesHolder = oldValues[i].clone(); 1364 anim.mValues[i] = newValuesHolder; 1365 anim.mValuesMap.put(newValuesHolder.getPropertyName(), newValuesHolder); 1366 } 1367 } 1368 return anim; 1369 } 1370 1371 /** 1372 * Implementors of this interface can add themselves as update listeners 1373 * to an <code>ValueAnimator</code> instance to receive callbacks on every animation 1374 * frame, after the current frame's values have been calculated for that 1375 * <code>ValueAnimator</code>. 1376 */ 1377 public static interface AnimatorUpdateListener { 1378 /** 1379 * <p>Notifies the occurrence of another frame of the animation.</p> 1380 * 1381 * @param animation The animation which was repeated. 1382 */ 1383 void onAnimationUpdate(ValueAnimator animation); 1384 1385 } 1386 1387 /** 1388 * Return the number of animations currently running. 1389 * 1390 * Used by StrictMode internally to annotate violations. 1391 * May be called on arbitrary threads! 1392 * 1393 * @hide 1394 */ 1395 public static int getCurrentAnimationsCount() { 1396 return AnimationHandler.getAnimationCount(); 1397 } 1398 1399 @Override 1400 public String toString() { 1401 String returnVal = "ValueAnimator@" + Integer.toHexString(hashCode()); 1402 if (mValues != null) { 1403 for (int i = 0; i < mValues.length; ++i) { 1404 returnVal += "\n " + mValues[i].toString(); 1405 } 1406 } 1407 return returnVal; 1408 } 1409 1410 /** 1411 * <p>Whether or not the ValueAnimator is allowed to run asynchronously off of 1412 * the UI thread. This is a hint that informs the ValueAnimator that it is 1413 * OK to run the animation off-thread, however ValueAnimator may decide 1414 * that it must run the animation on the UI thread anyway. For example if there 1415 * is an {@link AnimatorUpdateListener} the animation will run on the UI thread, 1416 * regardless of the value of this hint.</p> 1417 * 1418 * <p>Regardless of whether or not the animation runs asynchronously, all 1419 * listener callbacks will be called on the UI thread.</p> 1420 * 1421 * <p>To be able to use this hint the following must be true:</p> 1422 * <ol> 1423 * <li>{@link #getAnimatedFraction()} is not needed (it will return undefined values).</li> 1424 * <li>The animator is immutable while {@link #isStarted()} is true. Requests 1425 * to change values, duration, delay, etc... may be ignored.</li> 1426 * <li>Lifecycle callback events may be asynchronous. Events such as 1427 * {@link Animator.AnimatorListener#onAnimationEnd(Animator)} or 1428 * {@link Animator.AnimatorListener#onAnimationRepeat(Animator)} may end up delayed 1429 * as they must be posted back to the UI thread, and any actions performed 1430 * by those callbacks (such as starting new animations) will not happen 1431 * in the same frame.</li> 1432 * <li>State change requests ({@link #cancel()}, {@link #end()}, {@link #reverse()}, etc...) 1433 * may be asynchronous. It is guaranteed that all state changes that are 1434 * performed on the UI thread in the same frame will be applied as a single 1435 * atomic update, however that frame may be the current frame, 1436 * the next frame, or some future frame. This will also impact the observed 1437 * state of the Animator. For example, {@link #isStarted()} may still return true 1438 * after a call to {@link #end()}. Using the lifecycle callbacks is preferred over 1439 * queries to {@link #isStarted()}, {@link #isRunning()}, and {@link #isPaused()} 1440 * for this reason.</li> 1441 * </ol> 1442 * @hide 1443 */ 1444 @Override 1445 public void setAllowRunningAsynchronously(boolean mayRunAsync) { 1446 // It is up to subclasses to support this, if they can. 1447 } 1448} 1449