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.annotation.IntDef; 21 import android.annotation.TestApi; 22 import android.annotation.UnsupportedAppUsage; 23 import android.os.Build; 24 import android.os.Looper; 25 import android.os.Trace; 26 import android.util.AndroidRuntimeException; 27 import android.util.Log; 28 import android.view.animation.AccelerateDecelerateInterpolator; 29 import android.view.animation.Animation; 30 import android.view.animation.AnimationUtils; 31 import android.view.animation.LinearInterpolator; 32 33 import java.lang.annotation.Retention; 34 import java.lang.annotation.RetentionPolicy; 35 import java.util.ArrayList; 36 import java.util.HashMap; 37 38 /** 39 * This class provides a simple timing engine for running animations 40 * which calculate animated values and set them on target objects. 41 * 42 * <p>There is a single timing pulse that all animations use. It runs in a 43 * custom handler to ensure that property changes happen on the UI thread.</p> 44 * 45 * <p>By default, ValueAnimator uses non-linear time interpolation, via the 46 * {@link AccelerateDecelerateInterpolator} class, which accelerates into and decelerates 47 * out of an animation. This behavior can be changed by calling 48 * {@link ValueAnimator#setInterpolator(TimeInterpolator)}.</p> 49 * 50 * <p>Animators can be created from either code or resource files. Here is an example 51 * of a ValueAnimator resource file:</p> 52 * 53 * {@sample development/samples/ApiDemos/res/anim/animator.xml ValueAnimatorResources} 54 * 55 * <p>Starting from API 23, it is also possible to use a combination of {@link PropertyValuesHolder} 56 * and {@link Keyframe} resource tags to create a multi-step animation. 57 * Note that you can specify explicit fractional values (from 0 to 1) for 58 * each keyframe to determine when, in the overall duration, the animation should arrive at that 59 * value. Alternatively, you can leave the fractions off and the keyframes will be equally 60 * distributed within the total duration:</p> 61 * 62 * {@sample development/samples/ApiDemos/res/anim/value_animator_pvh_kf.xml 63 * ValueAnimatorKeyframeResources} 64 * 65 * <div class="special reference"> 66 * <h3>Developer Guides</h3> 67 * <p>For more information about animating with {@code ValueAnimator}, read the 68 * <a href="{@docRoot}guide/topics/graphics/prop-animation.html#value-animator">Property 69 * Animation</a> developer guide.</p> 70 * </div> 71 */ 72 @SuppressWarnings("unchecked") 73 public class ValueAnimator extends Animator implements AnimationHandler.AnimationFrameCallback { 74 private static final String TAG = "ValueAnimator"; 75 private static final boolean DEBUG = false; 76 77 /** 78 * Internal constants 79 */ 80 81 /** 82 * System-wide animation scale. 83 * 84 * <p>To check whether animations are enabled system-wise use {@link #areAnimatorsEnabled()}. 85 */ 86 @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P) 87 private static float sDurationScale = 1.0f; 88 89 /** 90 * Internal variables 91 * NOTE: This object implements the clone() method, making a deep copy of any referenced 92 * objects. As other non-trivial fields are added to this class, make sure to add logic 93 * to clone() to make deep copies of them. 94 */ 95 96 /** 97 * The first time that the animation's animateFrame() method is called. This time is used to 98 * determine elapsed time (and therefore the elapsed fraction) in subsequent calls 99 * to animateFrame(). 100 * 101 * Whenever mStartTime is set, you must also update mStartTimeCommitted. 102 */ 103 long mStartTime = -1; 104 105 /** 106 * When true, the start time has been firmly committed as a chosen reference point in 107 * time by which the progress of the animation will be evaluated. When false, the 108 * start time may be updated when the first animation frame is committed so as 109 * to compensate for jank that may have occurred between when the start time was 110 * initialized and when the frame was actually drawn. 111 * 112 * This flag is generally set to false during the first frame of the animation 113 * when the animation playing state transitions from STOPPED to RUNNING or 114 * resumes after having been paused. This flag is set to true when the start time 115 * is firmly committed and should not be further compensated for jank. 116 */ 117 boolean mStartTimeCommitted; 118 119 /** 120 * Set when setCurrentPlayTime() is called. If negative, animation is not currently seeked 121 * to a value. 122 */ 123 float mSeekFraction = -1; 124 125 /** 126 * Set on the next frame after pause() is called, used to calculate a new startTime 127 * or delayStartTime which allows the animator to continue from the point at which 128 * it was paused. If negative, has not yet been set. 129 */ 130 private long mPauseTime; 131 132 /** 133 * Set when an animator is resumed. This triggers logic in the next frame which 134 * actually resumes the animator. 135 */ 136 private boolean mResumed = false; 137 138 // The time interpolator to be used if none is set on the animation 139 private static final TimeInterpolator sDefaultInterpolator = 140 new AccelerateDecelerateInterpolator(); 141 142 /** 143 * Flag to indicate whether this animator is playing in reverse mode, specifically 144 * by being started or interrupted by a call to reverse(). This flag is different than 145 * mPlayingBackwards, which indicates merely whether the current iteration of the 146 * animator is playing in reverse. It is used in corner cases to determine proper end 147 * behavior. 148 */ 149 private boolean mReversing; 150 151 /** 152 * Tracks the overall fraction of the animation, ranging from 0 to mRepeatCount + 1 153 */ 154 private float mOverallFraction = 0f; 155 156 /** 157 * Tracks current elapsed/eased fraction, for querying in getAnimatedFraction(). 158 * This is calculated by interpolating the fraction (range: [0, 1]) in the current iteration. 159 */ 160 private float mCurrentFraction = 0f; 161 162 /** 163 * Tracks the time (in milliseconds) when the last frame arrived. 164 */ 165 private long mLastFrameTime = -1; 166 167 /** 168 * Tracks the time (in milliseconds) when the first frame arrived. Note the frame may arrive 169 * during the start delay. 170 */ 171 private long mFirstFrameTime = -1; 172 173 /** 174 * Additional playing state to indicate whether an animator has been start()'d. There is 175 * some lag between a call to start() and the first animation frame. We should still note 176 * that the animation has been started, even if it's first animation frame has not yet 177 * happened, and reflect that state in isRunning(). 178 * Note that delayed animations are different: they are not started until their first 179 * animation frame, which occurs after their delay elapses. 180 */ 181 private boolean mRunning = false; 182 183 /** 184 * Additional playing state to indicate whether an animator has been start()'d, whether or 185 * not there is a nonzero startDelay. 186 */ 187 private boolean mStarted = false; 188 189 /** 190 * Tracks whether we've notified listeners of the onAnimationStart() event. This can be 191 * complex to keep track of since we notify listeners at different times depending on 192 * startDelay and whether start() was called before end(). 193 */ 194 private boolean mStartListenersCalled = false; 195 196 /** 197 * Flag that denotes whether the animation is set up and ready to go. Used to 198 * set up animation that has not yet been started. 199 */ 200 boolean mInitialized = false; 201 202 /** 203 * Flag that tracks whether animation has been requested to end. 204 */ 205 private boolean mAnimationEndRequested = false; 206 207 // 208 // Backing variables 209 // 210 211 // How long the animation should last in ms 212 @UnsupportedAppUsage 213 private long mDuration = 300; 214 215 // The amount of time in ms to delay starting the animation after start() is called. Note 216 // that this start delay is unscaled. When there is a duration scale set on the animator, the 217 // scaling factor will be applied to this delay. 218 private long mStartDelay = 0; 219 220 // The number of times the animation will repeat. The default is 0, which means the animation 221 // will play only once 222 private int mRepeatCount = 0; 223 224 /** 225 * The type of repetition that will occur when repeatMode is nonzero. RESTART means the 226 * animation will start from the beginning on every new cycle. REVERSE means the animation 227 * will reverse directions on each iteration. 228 */ 229 private int mRepeatMode = RESTART; 230 231 /** 232 * Whether or not the animator should register for its own animation callback to receive 233 * animation pulse. 234 */ 235 private boolean mSelfPulse = true; 236 237 /** 238 * Whether or not the animator has been requested to start without pulsing. This flag gets set 239 * in startWithoutPulsing(), and reset in start(). 240 */ 241 private boolean mSuppressSelfPulseRequested = false; 242 243 /** 244 * The time interpolator to be used. The elapsed fraction of the animation will be passed 245 * through this interpolator to calculate the interpolated fraction, which is then used to 246 * calculate the animated values. 247 */ 248 private TimeInterpolator mInterpolator = sDefaultInterpolator; 249 250 /** 251 * The set of listeners to be sent events through the life of an animation. 252 */ 253 ArrayList<AnimatorUpdateListener> mUpdateListeners = null; 254 255 /** 256 * The property/value sets being animated. 257 */ 258 PropertyValuesHolder[] mValues; 259 260 /** 261 * A hashmap of the PropertyValuesHolder objects. This map is used to lookup animated values 262 * by property name during calls to getAnimatedValue(String). 263 */ 264 HashMap<String, PropertyValuesHolder> mValuesMap; 265 266 /** 267 * If set to non-negative value, this will override {@link #sDurationScale}. 268 */ 269 private float mDurationScale = -1f; 270 271 /** 272 * Public constants 273 */ 274 275 /** @hide */ 276 @IntDef({RESTART, REVERSE}) 277 @Retention(RetentionPolicy.SOURCE) 278 public @interface RepeatMode {} 279 280 /** 281 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 282 * or a positive value, the animation restarts from the beginning. 283 */ 284 public static final int RESTART = 1; 285 /** 286 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 287 * or a positive value, the animation reverses direction on every iteration. 288 */ 289 public static final int REVERSE = 2; 290 /** 291 * This value used used with the {@link #setRepeatCount(int)} property to repeat 292 * the animation indefinitely. 293 */ 294 public static final int INFINITE = -1; 295 296 /** 297 * @hide 298 */ 299 @TestApi setDurationScale(float durationScale)300 public static void setDurationScale(float durationScale) { 301 sDurationScale = durationScale; 302 } 303 304 /** 305 * @hide 306 */ 307 @TestApi getDurationScale()308 public static float getDurationScale() { 309 return sDurationScale; 310 } 311 312 /** 313 * Returns whether animators are currently enabled, system-wide. By default, all 314 * animators are enabled. This can change if either the user sets a Developer Option 315 * to set the animator duration scale to 0 or by Battery Savery mode being enabled 316 * (which disables all animations). 317 * 318 * <p>Developers should not typically need to call this method, but should an app wish 319 * to show a different experience when animators are disabled, this return value 320 * can be used as a decider of which experience to offer. 321 * 322 * @return boolean Whether animators are currently enabled. The default value is 323 * <code>true</code>. 324 */ areAnimatorsEnabled()325 public static boolean areAnimatorsEnabled() { 326 return !(sDurationScale == 0); 327 } 328 329 /** 330 * Creates a new ValueAnimator object. This default constructor is primarily for 331 * use internally; the factory methods which take parameters are more generally 332 * useful. 333 */ ValueAnimator()334 public ValueAnimator() { 335 } 336 337 /** 338 * Constructs and returns a ValueAnimator that animates between int values. A single 339 * value implies that that value is the one being animated to. However, this is not typically 340 * useful in a ValueAnimator object because there is no way for the object to determine the 341 * starting value for the animation (unlike ObjectAnimator, which can derive that value 342 * from the target object and property being animated). Therefore, there should typically 343 * be two or more values. 344 * 345 * @param values A set of values that the animation will animate between over time. 346 * @return A ValueAnimator object that is set up to animate between the given values. 347 */ ofInt(int... values)348 public static ValueAnimator ofInt(int... values) { 349 ValueAnimator anim = new ValueAnimator(); 350 anim.setIntValues(values); 351 return anim; 352 } 353 354 /** 355 * Constructs and returns a ValueAnimator that animates between color values. A single 356 * value implies that that value is the one being animated to. However, this is not typically 357 * useful in a ValueAnimator object because there is no way for the object to determine the 358 * starting value for the animation (unlike ObjectAnimator, which can derive that value 359 * from the target object and property being animated). Therefore, there should typically 360 * be two or more values. 361 * 362 * @param values A set of values that the animation will animate between over time. 363 * @return A ValueAnimator object that is set up to animate between the given values. 364 */ ofArgb(int... values)365 public static ValueAnimator ofArgb(int... values) { 366 ValueAnimator anim = new ValueAnimator(); 367 anim.setIntValues(values); 368 anim.setEvaluator(ArgbEvaluator.getInstance()); 369 return anim; 370 } 371 372 /** 373 * Constructs and returns a ValueAnimator that animates between float values. A single 374 * value implies that that value is the one being animated to. However, this is not typically 375 * useful in a ValueAnimator object because there is no way for the object to determine the 376 * starting value for the animation (unlike ObjectAnimator, which can derive that value 377 * from the target object and property being animated). Therefore, there should typically 378 * be two or more values. 379 * 380 * @param values A set of values that the animation will animate between over time. 381 * @return A ValueAnimator object that is set up to animate between the given values. 382 */ ofFloat(float... values)383 public static ValueAnimator ofFloat(float... values) { 384 ValueAnimator anim = new ValueAnimator(); 385 anim.setFloatValues(values); 386 return anim; 387 } 388 389 /** 390 * Constructs and returns a ValueAnimator that animates between the values 391 * specified in the PropertyValuesHolder objects. 392 * 393 * @param values A set of PropertyValuesHolder objects whose values will be animated 394 * between over time. 395 * @return A ValueAnimator object that is set up to animate between the given values. 396 */ ofPropertyValuesHolder(PropertyValuesHolder... values)397 public static ValueAnimator ofPropertyValuesHolder(PropertyValuesHolder... values) { 398 ValueAnimator anim = new ValueAnimator(); 399 anim.setValues(values); 400 return anim; 401 } 402 /** 403 * Constructs and returns a ValueAnimator that animates between Object values. A single 404 * value implies that that value is the one being animated to. However, this is not typically 405 * useful in a ValueAnimator object because there is no way for the object to determine the 406 * starting value for the animation (unlike ObjectAnimator, which can derive that value 407 * from the target object and property being animated). Therefore, there should typically 408 * be two or more values. 409 * 410 * <p><strong>Note:</strong> The Object values are stored as references to the original 411 * objects, which means that changes to those objects after this method is called will 412 * affect the values on the animator. If the objects will be mutated externally after 413 * this method is called, callers should pass a copy of those objects instead. 414 * 415 * <p>Since ValueAnimator does not know how to animate between arbitrary Objects, this 416 * factory method also takes a TypeEvaluator object that the ValueAnimator will use 417 * to perform that interpolation. 418 * 419 * @param evaluator A TypeEvaluator that will be called on each animation frame to 420 * provide the ncessry interpolation between the Object values to derive the animated 421 * value. 422 * @param values A set of values that the animation will animate between over time. 423 * @return A ValueAnimator object that is set up to animate between the given values. 424 */ ofObject(TypeEvaluator evaluator, Object... values)425 public static ValueAnimator ofObject(TypeEvaluator evaluator, Object... values) { 426 ValueAnimator anim = new ValueAnimator(); 427 anim.setObjectValues(values); 428 anim.setEvaluator(evaluator); 429 return anim; 430 } 431 432 /** 433 * Sets int values that will be animated between. A single 434 * value implies that that value is the one being animated to. However, this is not typically 435 * useful in a ValueAnimator object because there is no way for the object to determine the 436 * starting value for the animation (unlike ObjectAnimator, which can derive that value 437 * from the target object and property being animated). Therefore, there should typically 438 * be two or more values. 439 * 440 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 441 * than one PropertyValuesHolder object, this method will set the values for the first 442 * of those objects.</p> 443 * 444 * @param values A set of values that the animation will animate between over time. 445 */ setIntValues(int... values)446 public void setIntValues(int... values) { 447 if (values == null || values.length == 0) { 448 return; 449 } 450 if (mValues == null || mValues.length == 0) { 451 setValues(PropertyValuesHolder.ofInt("", values)); 452 } else { 453 PropertyValuesHolder valuesHolder = mValues[0]; 454 valuesHolder.setIntValues(values); 455 } 456 // New property/values/target should cause re-initialization prior to starting 457 mInitialized = false; 458 } 459 460 /** 461 * Sets float values that will be animated between. A single 462 * value implies that that value is the one being animated to. However, this is not typically 463 * useful in a ValueAnimator object because there is no way for the object to determine the 464 * starting value for the animation (unlike ObjectAnimator, which can derive that value 465 * from the target object and property being animated). Therefore, there should typically 466 * be two or more values. 467 * 468 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 469 * than one PropertyValuesHolder object, this method will set the values for the first 470 * of those objects.</p> 471 * 472 * @param values A set of values that the animation will animate between over time. 473 */ setFloatValues(float... values)474 public void setFloatValues(float... values) { 475 if (values == null || values.length == 0) { 476 return; 477 } 478 if (mValues == null || mValues.length == 0) { 479 setValues(PropertyValuesHolder.ofFloat("", values)); 480 } else { 481 PropertyValuesHolder valuesHolder = mValues[0]; 482 valuesHolder.setFloatValues(values); 483 } 484 // New property/values/target should cause re-initialization prior to starting 485 mInitialized = false; 486 } 487 488 /** 489 * Sets the values to animate between for this animation. A single 490 * value implies that that value is the one being animated to. However, this is not typically 491 * useful in a ValueAnimator object because there is no way for the object to determine the 492 * starting value for the animation (unlike ObjectAnimator, which can derive that value 493 * from the target object and property being animated). Therefore, there should typically 494 * be two or more values. 495 * 496 * <p><strong>Note:</strong> The Object values are stored as references to the original 497 * objects, which means that changes to those objects after this method is called will 498 * affect the values on the animator. If the objects will be mutated externally after 499 * this method is called, callers should pass a copy of those objects instead. 500 * 501 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 502 * than one PropertyValuesHolder object, this method will set the values for the first 503 * of those objects.</p> 504 * 505 * <p>There should be a TypeEvaluator set on the ValueAnimator that knows how to interpolate 506 * between these value objects. ValueAnimator only knows how to interpolate between the 507 * primitive types specified in the other setValues() methods.</p> 508 * 509 * @param values The set of values to animate between. 510 */ setObjectValues(Object... values)511 public void setObjectValues(Object... values) { 512 if (values == null || values.length == 0) { 513 return; 514 } 515 if (mValues == null || mValues.length == 0) { 516 setValues(PropertyValuesHolder.ofObject("", null, values)); 517 } else { 518 PropertyValuesHolder valuesHolder = mValues[0]; 519 valuesHolder.setObjectValues(values); 520 } 521 // New property/values/target should cause re-initialization prior to starting 522 mInitialized = false; 523 } 524 525 /** 526 * Sets the values, per property, being animated between. This function is called internally 527 * by the constructors of ValueAnimator that take a list of values. But a ValueAnimator can 528 * be constructed without values and this method can be called to set the values manually 529 * instead. 530 * 531 * @param values The set of values, per property, being animated between. 532 */ setValues(PropertyValuesHolder... values)533 public void setValues(PropertyValuesHolder... values) { 534 int numValues = values.length; 535 mValues = values; 536 mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 537 for (int i = 0; i < numValues; ++i) { 538 PropertyValuesHolder valuesHolder = values[i]; 539 mValuesMap.put(valuesHolder.getPropertyName(), valuesHolder); 540 } 541 // New property/values/target should cause re-initialization prior to starting 542 mInitialized = false; 543 } 544 545 /** 546 * Returns the values that this ValueAnimator animates between. These values are stored in 547 * PropertyValuesHolder objects, even if the ValueAnimator was created with a simple list 548 * of value objects instead. 549 * 550 * @return PropertyValuesHolder[] An array of PropertyValuesHolder objects which hold the 551 * values, per property, that define the animation. 552 */ getValues()553 public PropertyValuesHolder[] getValues() { 554 return mValues; 555 } 556 557 /** 558 * This function is called immediately before processing the first animation 559 * frame of an animation. If there is a nonzero <code>startDelay</code>, the 560 * function is called after that delay ends. 561 * It takes care of the final initialization steps for the 562 * animation. 563 * 564 * <p>Overrides of this method should call the superclass method to ensure 565 * that internal mechanisms for the animation are set up correctly.</p> 566 */ 567 @CallSuper initAnimation()568 void initAnimation() { 569 if (!mInitialized) { 570 int numValues = mValues.length; 571 for (int i = 0; i < numValues; ++i) { 572 mValues[i].init(); 573 } 574 mInitialized = true; 575 } 576 } 577 578 /** 579 * Sets the length of the animation. The default duration is 300 milliseconds. 580 * 581 * @param duration The length of the animation, in milliseconds. This value cannot 582 * be negative. 583 * @return ValueAnimator The object called with setDuration(). This return 584 * value makes it easier to compose statements together that construct and then set the 585 * duration, as in <code>ValueAnimator.ofInt(0, 10).setDuration(500).start()</code>. 586 */ 587 @Override setDuration(long duration)588 public ValueAnimator setDuration(long duration) { 589 if (duration < 0) { 590 throw new IllegalArgumentException("Animators cannot have negative duration: " + 591 duration); 592 } 593 mDuration = duration; 594 return this; 595 } 596 597 /** 598 * Overrides the global duration scale by a custom value. 599 * 600 * @param durationScale The duration scale to set; or {@code -1f} to use the global duration 601 * scale. 602 * @hide 603 */ overrideDurationScale(float durationScale)604 public void overrideDurationScale(float durationScale) { 605 mDurationScale = durationScale; 606 } 607 resolveDurationScale()608 private float resolveDurationScale() { 609 return mDurationScale >= 0f ? mDurationScale : sDurationScale; 610 } 611 getScaledDuration()612 private long getScaledDuration() { 613 return (long)(mDuration * resolveDurationScale()); 614 } 615 616 /** 617 * Gets the length of the animation. The default duration is 300 milliseconds. 618 * 619 * @return The length of the animation, in milliseconds. 620 */ 621 @Override getDuration()622 public long getDuration() { 623 return mDuration; 624 } 625 626 @Override getTotalDuration()627 public long getTotalDuration() { 628 if (mRepeatCount == INFINITE) { 629 return DURATION_INFINITE; 630 } else { 631 return mStartDelay + (mDuration * (mRepeatCount + 1)); 632 } 633 } 634 635 /** 636 * Sets the position of the animation to the specified point in time. This time should 637 * be between 0 and the total duration of the animation, including any repetition. If 638 * the animation has not yet been started, then it will not advance forward after it is 639 * set to this time; it will simply set the time to this value and perform any appropriate 640 * actions based on that time. If the animation is already running, then setCurrentPlayTime() 641 * will set the current playing time to this value and continue playing from that point. 642 * 643 * @param playTime The time, in milliseconds, to which the animation is advanced or rewound. 644 */ setCurrentPlayTime(long playTime)645 public void setCurrentPlayTime(long playTime) { 646 float fraction = mDuration > 0 ? (float) playTime / mDuration : 1; 647 setCurrentFraction(fraction); 648 } 649 650 /** 651 * Sets the position of the animation to the specified fraction. This fraction should 652 * be between 0 and the total fraction of the animation, including any repetition. That is, 653 * a fraction of 0 will position the animation at the beginning, a value of 1 at the end, 654 * and a value of 2 at the end of a reversing animator that repeats once. If 655 * the animation has not yet been started, then it will not advance forward after it is 656 * set to this fraction; it will simply set the fraction to this value and perform any 657 * appropriate actions based on that fraction. If the animation is already running, then 658 * setCurrentFraction() will set the current fraction to this value and continue 659 * playing from that point. {@link Animator.AnimatorListener} events are not called 660 * due to changing the fraction; those events are only processed while the animation 661 * is running. 662 * 663 * @param fraction The fraction to which the animation is advanced or rewound. Values 664 * outside the range of 0 to the maximum fraction for the animator will be clamped to 665 * the correct range. 666 */ setCurrentFraction(float fraction)667 public void setCurrentFraction(float fraction) { 668 initAnimation(); 669 fraction = clampFraction(fraction); 670 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 671 if (isPulsingInternal()) { 672 long seekTime = (long) (getScaledDuration() * fraction); 673 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 674 // Only modify the start time when the animation is running. Seek fraction will ensure 675 // non-running animations skip to the correct start time. 676 mStartTime = currentTime - seekTime; 677 } else { 678 // If the animation loop hasn't started, or during start delay, the startTime will be 679 // adjusted once the delay has passed based on seek fraction. 680 mSeekFraction = fraction; 681 } 682 mOverallFraction = fraction; 683 final float currentIterationFraction = getCurrentIterationFraction(fraction, mReversing); 684 animateValue(currentIterationFraction); 685 } 686 687 /** 688 * Calculates current iteration based on the overall fraction. The overall fraction will be 689 * in the range of [0, mRepeatCount + 1]. Both current iteration and fraction in the current 690 * iteration can be derived from it. 691 */ getCurrentIteration(float fraction)692 private int getCurrentIteration(float fraction) { 693 fraction = clampFraction(fraction); 694 // If the overall fraction is a positive integer, we consider the current iteration to be 695 // complete. In other words, the fraction for the current iteration would be 1, and the 696 // current iteration would be overall fraction - 1. 697 double iteration = Math.floor(fraction); 698 if (fraction == iteration && fraction > 0) { 699 iteration--; 700 } 701 return (int) iteration; 702 } 703 704 /** 705 * Calculates the fraction of the current iteration, taking into account whether the animation 706 * should be played backwards. E.g. When the animation is played backwards in an iteration, 707 * the fraction for that iteration will go from 1f to 0f. 708 */ getCurrentIterationFraction(float fraction, boolean inReverse)709 private float getCurrentIterationFraction(float fraction, boolean inReverse) { 710 fraction = clampFraction(fraction); 711 int iteration = getCurrentIteration(fraction); 712 float currentFraction = fraction - iteration; 713 return shouldPlayBackward(iteration, inReverse) ? 1f - currentFraction : currentFraction; 714 } 715 716 /** 717 * Clamps fraction into the correct range: [0, mRepeatCount + 1]. If repeat count is infinite, 718 * no upper bound will be set for the fraction. 719 * 720 * @param fraction fraction to be clamped 721 * @return fraction clamped into the range of [0, mRepeatCount + 1] 722 */ clampFraction(float fraction)723 private float clampFraction(float fraction) { 724 if (fraction < 0) { 725 fraction = 0; 726 } else if (mRepeatCount != INFINITE) { 727 fraction = Math.min(fraction, mRepeatCount + 1); 728 } 729 return fraction; 730 } 731 732 /** 733 * Calculates the direction of animation playing (i.e. forward or backward), based on 1) 734 * whether the entire animation is being reversed, 2) repeat mode applied to the current 735 * iteration. 736 */ shouldPlayBackward(int iteration, boolean inReverse)737 private boolean shouldPlayBackward(int iteration, boolean inReverse) { 738 if (iteration > 0 && mRepeatMode == REVERSE && 739 (iteration < (mRepeatCount + 1) || mRepeatCount == INFINITE)) { 740 // if we were seeked to some other iteration in a reversing animator, 741 // figure out the correct direction to start playing based on the iteration 742 if (inReverse) { 743 return (iteration % 2) == 0; 744 } else { 745 return (iteration % 2) != 0; 746 } 747 } else { 748 return inReverse; 749 } 750 } 751 752 /** 753 * Gets the current position of the animation in time, which is equal to the current 754 * time minus the time that the animation started. An animation that is not yet started will 755 * return a value of zero, unless the animation has has its play time set via 756 * {@link #setCurrentPlayTime(long)} or {@link #setCurrentFraction(float)}, in which case 757 * it will return the time that was set. 758 * 759 * @return The current position in time of the animation. 760 */ getCurrentPlayTime()761 public long getCurrentPlayTime() { 762 if (!mInitialized || (!mStarted && mSeekFraction < 0)) { 763 return 0; 764 } 765 if (mSeekFraction >= 0) { 766 return (long) (mDuration * mSeekFraction); 767 } 768 float durationScale = resolveDurationScale(); 769 if (durationScale == 0f) { 770 durationScale = 1f; 771 } 772 return (long) ((AnimationUtils.currentAnimationTimeMillis() - mStartTime) / durationScale); 773 } 774 775 /** 776 * The amount of time, in milliseconds, to delay starting the animation after 777 * {@link #start()} is called. 778 * 779 * @return the number of milliseconds to delay running the animation 780 */ 781 @Override getStartDelay()782 public long getStartDelay() { 783 return mStartDelay; 784 } 785 786 /** 787 * The amount of time, in milliseconds, to delay starting the animation after 788 * {@link #start()} is called. Note that the start delay should always be non-negative. Any 789 * negative start delay will be clamped to 0 on N and above. 790 * 791 * @param startDelay The amount of the delay, in milliseconds 792 */ 793 @Override setStartDelay(long startDelay)794 public void setStartDelay(long startDelay) { 795 // Clamp start delay to non-negative range. 796 if (startDelay < 0) { 797 Log.w(TAG, "Start delay should always be non-negative"); 798 startDelay = 0; 799 } 800 mStartDelay = startDelay; 801 } 802 803 /** 804 * The amount of time, in milliseconds, between each frame of the animation. This is a 805 * requested time that the animation will attempt to honor, but the actual delay between 806 * frames may be different, depending on system load and capabilities. This is a static 807 * function because the same delay will be applied to all animations, since they are all 808 * run off of a single timing loop. 809 * 810 * The frame delay may be ignored when the animation system uses an external timing 811 * source, such as the display refresh rate (vsync), to govern animations. 812 * 813 * Note that this method should be called from the same thread that {@link #start()} is 814 * called in order to check the frame delay for that animation. A runtime exception will be 815 * thrown if the calling thread does not have a Looper. 816 * 817 * @return the requested time between frames, in milliseconds 818 */ getFrameDelay()819 public static long getFrameDelay() { 820 return AnimationHandler.getInstance().getFrameDelay(); 821 } 822 823 /** 824 * The amount of time, in milliseconds, between each frame of the animation. This is a 825 * requested time that the animation will attempt to honor, but the actual delay between 826 * frames may be different, depending on system load and capabilities. This is a static 827 * function because the same delay will be applied to all animations, since they are all 828 * run off of a single timing loop. 829 * 830 * The frame delay may be ignored when the animation system uses an external timing 831 * source, such as the display refresh rate (vsync), to govern animations. 832 * 833 * Note that this method should be called from the same thread that {@link #start()} is 834 * called in order to have the new frame delay take effect on that animation. A runtime 835 * exception will be thrown if the calling thread does not have a Looper. 836 * 837 * @param frameDelay the requested time between frames, in milliseconds 838 */ setFrameDelay(long frameDelay)839 public static void setFrameDelay(long frameDelay) { 840 AnimationHandler.getInstance().setFrameDelay(frameDelay); 841 } 842 843 /** 844 * The most recent value calculated by this <code>ValueAnimator</code> when there is just one 845 * property being animated. This value is only sensible while the animation is running. The main 846 * purpose for this read-only property is to retrieve the value from the <code>ValueAnimator</code> 847 * during a call to {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 848 * is called during each animation frame, immediately after the value is calculated. 849 * 850 * @return animatedValue The value most recently calculated by this <code>ValueAnimator</code> for 851 * the single property being animated. If there are several properties being animated 852 * (specified by several PropertyValuesHolder objects in the constructor), this function 853 * returns the animated value for the first of those objects. 854 */ getAnimatedValue()855 public Object getAnimatedValue() { 856 if (mValues != null && mValues.length > 0) { 857 return mValues[0].getAnimatedValue(); 858 } 859 // Shouldn't get here; should always have values unless ValueAnimator was set up wrong 860 return null; 861 } 862 863 /** 864 * The most recent value calculated by this <code>ValueAnimator</code> for <code>propertyName</code>. 865 * The main purpose for this read-only property is to retrieve the value from the 866 * <code>ValueAnimator</code> during a call to 867 * {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 868 * is called during each animation frame, immediately after the value is calculated. 869 * 870 * @return animatedValue The value most recently calculated for the named property 871 * by this <code>ValueAnimator</code>. 872 */ getAnimatedValue(String propertyName)873 public Object getAnimatedValue(String propertyName) { 874 PropertyValuesHolder valuesHolder = mValuesMap.get(propertyName); 875 if (valuesHolder != null) { 876 return valuesHolder.getAnimatedValue(); 877 } else { 878 // At least avoid crashing if called with bogus propertyName 879 return null; 880 } 881 } 882 883 /** 884 * Sets how many times the animation should be repeated. If the repeat 885 * count is 0, the animation is never repeated. If the repeat count is 886 * greater than 0 or {@link #INFINITE}, the repeat mode will be taken 887 * into account. The repeat count is 0 by default. 888 * 889 * @param value the number of times the animation should be repeated 890 */ setRepeatCount(int value)891 public void setRepeatCount(int value) { 892 mRepeatCount = value; 893 } 894 /** 895 * Defines how many times the animation should repeat. The default value 896 * is 0. 897 * 898 * @return the number of times the animation should repeat, or {@link #INFINITE} 899 */ getRepeatCount()900 public int getRepeatCount() { 901 return mRepeatCount; 902 } 903 904 /** 905 * Defines what this animation should do when it reaches the end. This 906 * setting is applied only when the repeat count is either greater than 907 * 0 or {@link #INFINITE}. Defaults to {@link #RESTART}. 908 * 909 * @param value {@link #RESTART} or {@link #REVERSE} 910 */ setRepeatMode(@epeatMode int value)911 public void setRepeatMode(@RepeatMode int value) { 912 mRepeatMode = value; 913 } 914 915 /** 916 * Defines what this animation should do when it reaches the end. 917 * 918 * @return either one of {@link #REVERSE} or {@link #RESTART} 919 */ 920 @RepeatMode getRepeatMode()921 public int getRepeatMode() { 922 return mRepeatMode; 923 } 924 925 /** 926 * Adds a listener to the set of listeners that are sent update events through the life of 927 * an animation. This method is called on all listeners for every frame of the animation, 928 * after the values for the animation have been calculated. 929 * 930 * @param listener the listener to be added to the current set of listeners for this animation. 931 */ addUpdateListener(AnimatorUpdateListener listener)932 public void addUpdateListener(AnimatorUpdateListener listener) { 933 if (mUpdateListeners == null) { 934 mUpdateListeners = new ArrayList<AnimatorUpdateListener>(); 935 } 936 mUpdateListeners.add(listener); 937 } 938 939 /** 940 * Removes all listeners from the set listening to frame updates for this animation. 941 */ removeAllUpdateListeners()942 public void removeAllUpdateListeners() { 943 if (mUpdateListeners == null) { 944 return; 945 } 946 mUpdateListeners.clear(); 947 mUpdateListeners = null; 948 } 949 950 /** 951 * Removes a listener from the set listening to frame updates for this animation. 952 * 953 * @param listener the listener to be removed from the current set of update listeners 954 * for this animation. 955 */ removeUpdateListener(AnimatorUpdateListener listener)956 public void removeUpdateListener(AnimatorUpdateListener listener) { 957 if (mUpdateListeners == null) { 958 return; 959 } 960 mUpdateListeners.remove(listener); 961 if (mUpdateListeners.size() == 0) { 962 mUpdateListeners = null; 963 } 964 } 965 966 967 /** 968 * The time interpolator used in calculating the elapsed fraction of this animation. The 969 * interpolator determines whether the animation runs with linear or non-linear motion, 970 * such as acceleration and deceleration. The default value is 971 * {@link android.view.animation.AccelerateDecelerateInterpolator} 972 * 973 * @param value the interpolator to be used by this animation. A value of <code>null</code> 974 * will result in linear interpolation. 975 */ 976 @Override setInterpolator(TimeInterpolator value)977 public void setInterpolator(TimeInterpolator value) { 978 if (value != null) { 979 mInterpolator = value; 980 } else { 981 mInterpolator = new LinearInterpolator(); 982 } 983 } 984 985 /** 986 * Returns the timing interpolator that this ValueAnimator uses. 987 * 988 * @return The timing interpolator for this ValueAnimator. 989 */ 990 @Override getInterpolator()991 public TimeInterpolator getInterpolator() { 992 return mInterpolator; 993 } 994 995 /** 996 * The type evaluator to be used when calculating the animated values of this animation. 997 * The system will automatically assign a float or int evaluator based on the type 998 * of <code>startValue</code> and <code>endValue</code> in the constructor. But if these values 999 * are not one of these primitive types, or if different evaluation is desired (such as is 1000 * necessary with int values that represent colors), a custom evaluator needs to be assigned. 1001 * For example, when running an animation on color values, the {@link ArgbEvaluator} 1002 * should be used to get correct RGB color interpolation. 1003 * 1004 * <p>If this ValueAnimator has only one set of values being animated between, this evaluator 1005 * will be used for that set. If there are several sets of values being animated, which is 1006 * the case if PropertyValuesHolder objects were set on the ValueAnimator, then the evaluator 1007 * is assigned just to the first PropertyValuesHolder object.</p> 1008 * 1009 * @param value the evaluator to be used this animation 1010 */ setEvaluator(TypeEvaluator value)1011 public void setEvaluator(TypeEvaluator value) { 1012 if (value != null && mValues != null && mValues.length > 0) { 1013 mValues[0].setEvaluator(value); 1014 } 1015 } 1016 notifyStartListeners()1017 private void notifyStartListeners() { 1018 if (mListeners != null && !mStartListenersCalled) { 1019 ArrayList<AnimatorListener> tmpListeners = 1020 (ArrayList<AnimatorListener>) mListeners.clone(); 1021 int numListeners = tmpListeners.size(); 1022 for (int i = 0; i < numListeners; ++i) { 1023 tmpListeners.get(i).onAnimationStart(this, mReversing); 1024 } 1025 } 1026 mStartListenersCalled = true; 1027 } 1028 1029 /** 1030 * Start the animation playing. This version of start() takes a boolean flag that indicates 1031 * whether the animation should play in reverse. The flag is usually false, but may be set 1032 * to true if called from the reverse() method. 1033 * 1034 * <p>The animation started by calling this method will be run on the thread that called 1035 * this method. This thread should have a Looper on it (a runtime exception will be thrown if 1036 * this is not the case). Also, if the animation will animate 1037 * properties of objects in the view hierarchy, then the calling thread should be the UI 1038 * thread for that view hierarchy.</p> 1039 * 1040 * @param playBackwards Whether the ValueAnimator should start playing in reverse. 1041 */ start(boolean playBackwards)1042 private void start(boolean playBackwards) { 1043 if (Looper.myLooper() == null) { 1044 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 1045 } 1046 mReversing = playBackwards; 1047 mSelfPulse = !mSuppressSelfPulseRequested; 1048 // Special case: reversing from seek-to-0 should act as if not seeked at all. 1049 if (playBackwards && mSeekFraction != -1 && mSeekFraction != 0) { 1050 if (mRepeatCount == INFINITE) { 1051 // Calculate the fraction of the current iteration. 1052 float fraction = (float) (mSeekFraction - Math.floor(mSeekFraction)); 1053 mSeekFraction = 1 - fraction; 1054 } else { 1055 mSeekFraction = 1 + mRepeatCount - mSeekFraction; 1056 } 1057 } 1058 mStarted = true; 1059 mPaused = false; 1060 mRunning = false; 1061 mAnimationEndRequested = false; 1062 // Resets mLastFrameTime when start() is called, so that if the animation was running, 1063 // calling start() would put the animation in the 1064 // started-but-not-yet-reached-the-first-frame phase. 1065 mLastFrameTime = -1; 1066 mFirstFrameTime = -1; 1067 mStartTime = -1; 1068 addAnimationCallback(0); 1069 1070 if (mStartDelay == 0 || mSeekFraction >= 0 || mReversing) { 1071 // If there's no start delay, init the animation and notify start listeners right away 1072 // to be consistent with the previous behavior. Otherwise, postpone this until the first 1073 // frame after the start delay. 1074 startAnimation(); 1075 if (mSeekFraction == -1) { 1076 // No seek, start at play time 0. Note that the reason we are not using fraction 0 1077 // is because for animations with 0 duration, we want to be consistent with pre-N 1078 // behavior: skip to the final value immediately. 1079 setCurrentPlayTime(0); 1080 } else { 1081 setCurrentFraction(mSeekFraction); 1082 } 1083 } 1084 } 1085 startWithoutPulsing(boolean inReverse)1086 void startWithoutPulsing(boolean inReverse) { 1087 mSuppressSelfPulseRequested = true; 1088 if (inReverse) { 1089 reverse(); 1090 } else { 1091 start(); 1092 } 1093 mSuppressSelfPulseRequested = false; 1094 } 1095 1096 @Override start()1097 public void start() { 1098 start(false); 1099 } 1100 1101 @Override cancel()1102 public void cancel() { 1103 if (Looper.myLooper() == null) { 1104 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 1105 } 1106 1107 // If end has already been requested, through a previous end() or cancel() call, no-op 1108 // until animation starts again. 1109 if (mAnimationEndRequested) { 1110 return; 1111 } 1112 1113 // Only cancel if the animation is actually running or has been started and is about 1114 // to run 1115 // Only notify listeners if the animator has actually started 1116 if ((mStarted || mRunning) && mListeners != null) { 1117 if (!mRunning) { 1118 // If it's not yet running, then start listeners weren't called. Call them now. 1119 notifyStartListeners(); 1120 } 1121 ArrayList<AnimatorListener> tmpListeners = 1122 (ArrayList<AnimatorListener>) mListeners.clone(); 1123 for (AnimatorListener listener : tmpListeners) { 1124 listener.onAnimationCancel(this); 1125 } 1126 } 1127 endAnimation(); 1128 1129 } 1130 1131 @Override end()1132 public void end() { 1133 if (Looper.myLooper() == null) { 1134 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 1135 } 1136 if (!mRunning) { 1137 // Special case if the animation has not yet started; get it ready for ending 1138 startAnimation(); 1139 mStarted = true; 1140 } else if (!mInitialized) { 1141 initAnimation(); 1142 } 1143 animateValue(shouldPlayBackward(mRepeatCount, mReversing) ? 0f : 1f); 1144 endAnimation(); 1145 } 1146 1147 @Override resume()1148 public void resume() { 1149 if (Looper.myLooper() == null) { 1150 throw new AndroidRuntimeException("Animators may only be resumed from the same " + 1151 "thread that the animator was started on"); 1152 } 1153 if (mPaused && !mResumed) { 1154 mResumed = true; 1155 if (mPauseTime > 0) { 1156 addAnimationCallback(0); 1157 } 1158 } 1159 super.resume(); 1160 } 1161 1162 @Override pause()1163 public void pause() { 1164 boolean previouslyPaused = mPaused; 1165 super.pause(); 1166 if (!previouslyPaused && mPaused) { 1167 mPauseTime = -1; 1168 mResumed = false; 1169 } 1170 } 1171 1172 @Override isRunning()1173 public boolean isRunning() { 1174 return mRunning; 1175 } 1176 1177 @Override isStarted()1178 public boolean isStarted() { 1179 return mStarted; 1180 } 1181 1182 /** 1183 * Plays the ValueAnimator in reverse. If the animation is already running, 1184 * it will stop itself and play backwards from the point reached when reverse was called. 1185 * If the animation is not currently running, then it will start from the end and 1186 * play backwards. This behavior is only set for the current animation; future playing 1187 * of the animation will use the default behavior of playing forward. 1188 */ 1189 @Override reverse()1190 public void reverse() { 1191 if (isPulsingInternal()) { 1192 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 1193 long currentPlayTime = currentTime - mStartTime; 1194 long timeLeft = getScaledDuration() - currentPlayTime; 1195 mStartTime = currentTime - timeLeft; 1196 mStartTimeCommitted = true; // do not allow start time to be compensated for jank 1197 mReversing = !mReversing; 1198 } else if (mStarted) { 1199 mReversing = !mReversing; 1200 end(); 1201 } else { 1202 start(true); 1203 } 1204 } 1205 1206 /** 1207 * @hide 1208 */ 1209 @Override canReverse()1210 public boolean canReverse() { 1211 return true; 1212 } 1213 1214 /** 1215 * Called internally to end an animation by removing it from the animations list. Must be 1216 * called on the UI thread. 1217 */ endAnimation()1218 private void endAnimation() { 1219 if (mAnimationEndRequested) { 1220 return; 1221 } 1222 removeAnimationCallback(); 1223 1224 mAnimationEndRequested = true; 1225 mPaused = false; 1226 boolean notify = (mStarted || mRunning) && mListeners != null; 1227 if (notify && !mRunning) { 1228 // If it's not yet running, then start listeners weren't called. Call them now. 1229 notifyStartListeners(); 1230 } 1231 mRunning = false; 1232 mStarted = false; 1233 mStartListenersCalled = false; 1234 mLastFrameTime = -1; 1235 mFirstFrameTime = -1; 1236 mStartTime = -1; 1237 if (notify && mListeners != null) { 1238 ArrayList<AnimatorListener> tmpListeners = 1239 (ArrayList<AnimatorListener>) mListeners.clone(); 1240 int numListeners = tmpListeners.size(); 1241 for (int i = 0; i < numListeners; ++i) { 1242 tmpListeners.get(i).onAnimationEnd(this, mReversing); 1243 } 1244 } 1245 // mReversing needs to be reset *after* notifying the listeners for the end callbacks. 1246 mReversing = false; 1247 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1248 Trace.asyncTraceEnd(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1249 System.identityHashCode(this)); 1250 } 1251 } 1252 1253 /** 1254 * Called internally to start an animation by adding it to the active animations list. Must be 1255 * called on the UI thread. 1256 */ startAnimation()1257 private void startAnimation() { 1258 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1259 Trace.asyncTraceBegin(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1260 System.identityHashCode(this)); 1261 } 1262 1263 mAnimationEndRequested = false; 1264 initAnimation(); 1265 mRunning = true; 1266 if (mSeekFraction >= 0) { 1267 mOverallFraction = mSeekFraction; 1268 } else { 1269 mOverallFraction = 0f; 1270 } 1271 if (mListeners != null) { 1272 notifyStartListeners(); 1273 } 1274 } 1275 1276 /** 1277 * Internal only: This tracks whether the animation has gotten on the animation loop. Note 1278 * this is different than {@link #isRunning()} in that the latter tracks the time after start() 1279 * is called (or after start delay if any), which may be before the animation loop starts. 1280 */ isPulsingInternal()1281 private boolean isPulsingInternal() { 1282 return mLastFrameTime >= 0; 1283 } 1284 1285 /** 1286 * Returns the name of this animator for debugging purposes. 1287 */ getNameForTrace()1288 String getNameForTrace() { 1289 return "animator"; 1290 } 1291 1292 /** 1293 * Applies an adjustment to the animation to compensate for jank between when 1294 * the animation first ran and when the frame was drawn. 1295 * @hide 1296 */ commitAnimationFrame(long frameTime)1297 public void commitAnimationFrame(long frameTime) { 1298 if (!mStartTimeCommitted) { 1299 mStartTimeCommitted = true; 1300 long adjustment = frameTime - mLastFrameTime; 1301 if (adjustment > 0) { 1302 mStartTime += adjustment; 1303 if (DEBUG) { 1304 Log.d(TAG, "Adjusted start time by " + adjustment + " ms: " + toString()); 1305 } 1306 } 1307 } 1308 } 1309 1310 /** 1311 * This internal function processes a single animation frame for a given animation. The 1312 * currentTime parameter is the timing pulse sent by the handler, used to calculate the 1313 * elapsed duration, and therefore 1314 * the elapsed fraction, of the animation. The return value indicates whether the animation 1315 * should be ended (which happens when the elapsed time of the animation exceeds the 1316 * animation's duration, including the repeatCount). 1317 * 1318 * @param currentTime The current time, as tracked by the static timing handler 1319 * @return true if the animation's duration, including any repetitions due to 1320 * <code>repeatCount</code> has been exceeded and the animation should be ended. 1321 */ animateBasedOnTime(long currentTime)1322 boolean animateBasedOnTime(long currentTime) { 1323 boolean done = false; 1324 if (mRunning) { 1325 final long scaledDuration = getScaledDuration(); 1326 final float fraction = scaledDuration > 0 ? 1327 (float)(currentTime - mStartTime) / scaledDuration : 1f; 1328 final float lastFraction = mOverallFraction; 1329 final boolean newIteration = (int) fraction > (int) lastFraction; 1330 final boolean lastIterationFinished = (fraction >= mRepeatCount + 1) && 1331 (mRepeatCount != INFINITE); 1332 if (scaledDuration == 0) { 1333 // 0 duration animator, ignore the repeat count and skip to the end 1334 done = true; 1335 } else if (newIteration && !lastIterationFinished) { 1336 // Time to repeat 1337 if (mListeners != null) { 1338 int numListeners = mListeners.size(); 1339 for (int i = 0; i < numListeners; ++i) { 1340 mListeners.get(i).onAnimationRepeat(this); 1341 } 1342 } 1343 } else if (lastIterationFinished) { 1344 done = true; 1345 } 1346 mOverallFraction = clampFraction(fraction); 1347 float currentIterationFraction = getCurrentIterationFraction( 1348 mOverallFraction, mReversing); 1349 animateValue(currentIterationFraction); 1350 } 1351 return done; 1352 } 1353 1354 /** 1355 * Internal use only. 1356 * 1357 * This method does not modify any fields of the animation. It should be called when seeking 1358 * in an AnimatorSet. When the last play time and current play time are of different repeat 1359 * iterations, 1360 * {@link android.view.animation.Animation.AnimationListener#onAnimationRepeat(Animation)} 1361 * will be called. 1362 */ 1363 @Override animateBasedOnPlayTime(long currentPlayTime, long lastPlayTime, boolean inReverse)1364 void animateBasedOnPlayTime(long currentPlayTime, long lastPlayTime, boolean inReverse) { 1365 if (currentPlayTime < 0 || lastPlayTime < 0) { 1366 throw new UnsupportedOperationException("Error: Play time should never be negative."); 1367 } 1368 1369 initAnimation(); 1370 // Check whether repeat callback is needed only when repeat count is non-zero 1371 if (mRepeatCount > 0) { 1372 int iteration = (int) (currentPlayTime / mDuration); 1373 int lastIteration = (int) (lastPlayTime / mDuration); 1374 1375 // Clamp iteration to [0, mRepeatCount] 1376 iteration = Math.min(iteration, mRepeatCount); 1377 lastIteration = Math.min(lastIteration, mRepeatCount); 1378 1379 if (iteration != lastIteration) { 1380 if (mListeners != null) { 1381 int numListeners = mListeners.size(); 1382 for (int i = 0; i < numListeners; ++i) { 1383 mListeners.get(i).onAnimationRepeat(this); 1384 } 1385 } 1386 } 1387 } 1388 1389 if (mRepeatCount != INFINITE && currentPlayTime >= (mRepeatCount + 1) * mDuration) { 1390 skipToEndValue(inReverse); 1391 } else { 1392 // Find the current fraction: 1393 float fraction = currentPlayTime / (float) mDuration; 1394 fraction = getCurrentIterationFraction(fraction, inReverse); 1395 animateValue(fraction); 1396 } 1397 } 1398 1399 /** 1400 * Internal use only. 1401 * Skips the animation value to end/start, depending on whether the play direction is forward 1402 * or backward. 1403 * 1404 * @param inReverse whether the end value is based on a reverse direction. If yes, this is 1405 * equivalent to skip to start value in a forward playing direction. 1406 */ skipToEndValue(boolean inReverse)1407 void skipToEndValue(boolean inReverse) { 1408 initAnimation(); 1409 float endFraction = inReverse ? 0f : 1f; 1410 if (mRepeatCount % 2 == 1 && mRepeatMode == REVERSE) { 1411 // This would end on fraction = 0 1412 endFraction = 0f; 1413 } 1414 animateValue(endFraction); 1415 } 1416 1417 @Override isInitialized()1418 boolean isInitialized() { 1419 return mInitialized; 1420 } 1421 1422 /** 1423 * Processes a frame of the animation, adjusting the start time if needed. 1424 * 1425 * @param frameTime The frame time. 1426 * @return true if the animation has ended. 1427 * @hide 1428 */ doAnimationFrame(long frameTime)1429 public final boolean doAnimationFrame(long frameTime) { 1430 if (mStartTime < 0) { 1431 // First frame. If there is start delay, start delay count down will happen *after* this 1432 // frame. 1433 mStartTime = mReversing 1434 ? frameTime 1435 : frameTime + (long) (mStartDelay * resolveDurationScale()); 1436 } 1437 1438 // Handle pause/resume 1439 if (mPaused) { 1440 mPauseTime = frameTime; 1441 removeAnimationCallback(); 1442 return false; 1443 } else if (mResumed) { 1444 mResumed = false; 1445 if (mPauseTime > 0) { 1446 // Offset by the duration that the animation was paused 1447 mStartTime += (frameTime - mPauseTime); 1448 } 1449 } 1450 1451 if (!mRunning) { 1452 // If not running, that means the animation is in the start delay phase of a forward 1453 // running animation. In the case of reversing, we want to run start delay in the end. 1454 if (mStartTime > frameTime && mSeekFraction == -1) { 1455 // This is when no seek fraction is set during start delay. If developers change the 1456 // seek fraction during the delay, animation will start from the seeked position 1457 // right away. 1458 return false; 1459 } else { 1460 // If mRunning is not set by now, that means non-zero start delay, 1461 // no seeking, not reversing. At this point, start delay has passed. 1462 mRunning = true; 1463 startAnimation(); 1464 } 1465 } 1466 1467 if (mLastFrameTime < 0) { 1468 if (mSeekFraction >= 0) { 1469 long seekTime = (long) (getScaledDuration() * mSeekFraction); 1470 mStartTime = frameTime - seekTime; 1471 mSeekFraction = -1; 1472 } 1473 mStartTimeCommitted = false; // allow start time to be compensated for jank 1474 } 1475 mLastFrameTime = frameTime; 1476 // The frame time might be before the start time during the first frame of 1477 // an animation. The "current time" must always be on or after the start 1478 // time to avoid animating frames at negative time intervals. In practice, this 1479 // is very rare and only happens when seeking backwards. 1480 final long currentTime = Math.max(frameTime, mStartTime); 1481 boolean finished = animateBasedOnTime(currentTime); 1482 1483 if (finished) { 1484 endAnimation(); 1485 } 1486 return finished; 1487 } 1488 1489 @Override pulseAnimationFrame(long frameTime)1490 boolean pulseAnimationFrame(long frameTime) { 1491 if (mSelfPulse) { 1492 // Pulse animation frame will *always* be after calling start(). If mSelfPulse isn't 1493 // set to false at this point, that means child animators did not call super's start(). 1494 // This can happen when the Animator is just a non-animating wrapper around a real 1495 // functional animation. In this case, we can't really pulse a frame into the animation, 1496 // because the animation cannot necessarily be properly initialized (i.e. no start/end 1497 // values set). 1498 return false; 1499 } 1500 return doAnimationFrame(frameTime); 1501 } 1502 addOneShotCommitCallback()1503 private void addOneShotCommitCallback() { 1504 if (!mSelfPulse) { 1505 return; 1506 } 1507 getAnimationHandler().addOneShotCommitCallback(this); 1508 } 1509 removeAnimationCallback()1510 private void removeAnimationCallback() { 1511 if (!mSelfPulse) { 1512 return; 1513 } 1514 getAnimationHandler().removeCallback(this); 1515 } 1516 addAnimationCallback(long delay)1517 private void addAnimationCallback(long delay) { 1518 if (!mSelfPulse) { 1519 return; 1520 } 1521 getAnimationHandler().addAnimationFrameCallback(this, delay); 1522 } 1523 1524 /** 1525 * Returns the current animation fraction, which is the elapsed/interpolated fraction used in 1526 * the most recent frame update on the animation. 1527 * 1528 * @return Elapsed/interpolated fraction of the animation. 1529 */ getAnimatedFraction()1530 public float getAnimatedFraction() { 1531 return mCurrentFraction; 1532 } 1533 1534 /** 1535 * This method is called with the elapsed fraction of the animation during every 1536 * animation frame. This function turns the elapsed fraction into an interpolated fraction 1537 * and then into an animated value (from the evaluator. The function is called mostly during 1538 * animation updates, but it is also called when the <code>end()</code> 1539 * function is called, to set the final value on the property. 1540 * 1541 * <p>Overrides of this method must call the superclass to perform the calculation 1542 * of the animated value.</p> 1543 * 1544 * @param fraction The elapsed fraction of the animation. 1545 */ 1546 @CallSuper 1547 @UnsupportedAppUsage animateValue(float fraction)1548 void animateValue(float fraction) { 1549 fraction = mInterpolator.getInterpolation(fraction); 1550 mCurrentFraction = fraction; 1551 int numValues = mValues.length; 1552 for (int i = 0; i < numValues; ++i) { 1553 mValues[i].calculateValue(fraction); 1554 } 1555 if (mUpdateListeners != null) { 1556 int numListeners = mUpdateListeners.size(); 1557 for (int i = 0; i < numListeners; ++i) { 1558 mUpdateListeners.get(i).onAnimationUpdate(this); 1559 } 1560 } 1561 } 1562 1563 @Override clone()1564 public ValueAnimator clone() { 1565 final ValueAnimator anim = (ValueAnimator) super.clone(); 1566 if (mUpdateListeners != null) { 1567 anim.mUpdateListeners = new ArrayList<AnimatorUpdateListener>(mUpdateListeners); 1568 } 1569 anim.mSeekFraction = -1; 1570 anim.mReversing = false; 1571 anim.mInitialized = false; 1572 anim.mStarted = false; 1573 anim.mRunning = false; 1574 anim.mPaused = false; 1575 anim.mResumed = false; 1576 anim.mStartListenersCalled = false; 1577 anim.mStartTime = -1; 1578 anim.mStartTimeCommitted = false; 1579 anim.mAnimationEndRequested = false; 1580 anim.mPauseTime = -1; 1581 anim.mLastFrameTime = -1; 1582 anim.mFirstFrameTime = -1; 1583 anim.mOverallFraction = 0; 1584 anim.mCurrentFraction = 0; 1585 anim.mSelfPulse = true; 1586 anim.mSuppressSelfPulseRequested = false; 1587 1588 PropertyValuesHolder[] oldValues = mValues; 1589 if (oldValues != null) { 1590 int numValues = oldValues.length; 1591 anim.mValues = new PropertyValuesHolder[numValues]; 1592 anim.mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 1593 for (int i = 0; i < numValues; ++i) { 1594 PropertyValuesHolder newValuesHolder = oldValues[i].clone(); 1595 anim.mValues[i] = newValuesHolder; 1596 anim.mValuesMap.put(newValuesHolder.getPropertyName(), newValuesHolder); 1597 } 1598 } 1599 return anim; 1600 } 1601 1602 /** 1603 * Implementors of this interface can add themselves as update listeners 1604 * to an <code>ValueAnimator</code> instance to receive callbacks on every animation 1605 * frame, after the current frame's values have been calculated for that 1606 * <code>ValueAnimator</code>. 1607 */ 1608 public static interface AnimatorUpdateListener { 1609 /** 1610 * <p>Notifies the occurrence of another frame of the animation.</p> 1611 * 1612 * @param animation The animation which was repeated. 1613 */ onAnimationUpdate(ValueAnimator animation)1614 void onAnimationUpdate(ValueAnimator animation); 1615 1616 } 1617 1618 /** 1619 * Return the number of animations currently running. 1620 * 1621 * Used by StrictMode internally to annotate violations. 1622 * May be called on arbitrary threads! 1623 * 1624 * @hide 1625 */ getCurrentAnimationsCount()1626 public static int getCurrentAnimationsCount() { 1627 return AnimationHandler.getAnimationCount(); 1628 } 1629 1630 @Override toString()1631 public String toString() { 1632 String returnVal = "ValueAnimator@" + Integer.toHexString(hashCode()); 1633 if (mValues != null) { 1634 for (int i = 0; i < mValues.length; ++i) { 1635 returnVal += "\n " + mValues[i].toString(); 1636 } 1637 } 1638 return returnVal; 1639 } 1640 1641 /** 1642 * <p>Whether or not the ValueAnimator is allowed to run asynchronously off of 1643 * the UI thread. This is a hint that informs the ValueAnimator that it is 1644 * OK to run the animation off-thread, however ValueAnimator may decide 1645 * that it must run the animation on the UI thread anyway. For example if there 1646 * is an {@link AnimatorUpdateListener} the animation will run on the UI thread, 1647 * regardless of the value of this hint.</p> 1648 * 1649 * <p>Regardless of whether or not the animation runs asynchronously, all 1650 * listener callbacks will be called on the UI thread.</p> 1651 * 1652 * <p>To be able to use this hint the following must be true:</p> 1653 * <ol> 1654 * <li>{@link #getAnimatedFraction()} is not needed (it will return undefined values).</li> 1655 * <li>The animator is immutable while {@link #isStarted()} is true. Requests 1656 * to change values, duration, delay, etc... may be ignored.</li> 1657 * <li>Lifecycle callback events may be asynchronous. Events such as 1658 * {@link Animator.AnimatorListener#onAnimationEnd(Animator)} or 1659 * {@link Animator.AnimatorListener#onAnimationRepeat(Animator)} may end up delayed 1660 * as they must be posted back to the UI thread, and any actions performed 1661 * by those callbacks (such as starting new animations) will not happen 1662 * in the same frame.</li> 1663 * <li>State change requests ({@link #cancel()}, {@link #end()}, {@link #reverse()}, etc...) 1664 * may be asynchronous. It is guaranteed that all state changes that are 1665 * performed on the UI thread in the same frame will be applied as a single 1666 * atomic update, however that frame may be the current frame, 1667 * the next frame, or some future frame. This will also impact the observed 1668 * state of the Animator. For example, {@link #isStarted()} may still return true 1669 * after a call to {@link #end()}. Using the lifecycle callbacks is preferred over 1670 * queries to {@link #isStarted()}, {@link #isRunning()}, and {@link #isPaused()} 1671 * for this reason.</li> 1672 * </ol> 1673 * @hide 1674 */ 1675 @Override setAllowRunningAsynchronously(boolean mayRunAsync)1676 public void setAllowRunningAsynchronously(boolean mayRunAsync) { 1677 // It is up to subclasses to support this, if they can. 1678 } 1679 1680 /** 1681 * @return The {@link AnimationHandler} that will be used to schedule updates for this animator. 1682 * @hide 1683 */ getAnimationHandler()1684 public AnimationHandler getAnimationHandler() { 1685 return AnimationHandler.getInstance(); 1686 } 1687 } 1688