ValueAnimator.java revision 1ffb280a7d2c70cc16d709c685f5d31fdb86b5e4
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.os.Looper; 20import android.os.Trace; 21import android.util.AndroidRuntimeException; 22import android.view.Choreographer; 23import android.view.animation.AccelerateDecelerateInterpolator; 24import android.view.animation.AnimationUtils; 25import android.view.animation.LinearInterpolator; 26 27import java.util.ArrayList; 28import java.util.HashMap; 29 30/** 31 * This class provides a simple timing engine for running animations 32 * which calculate animated values and set them on target objects. 33 * 34 * <p>There is a single timing pulse that all animations use. It runs in a 35 * custom handler to ensure that property changes happen on the UI thread.</p> 36 * 37 * <p>By default, ValueAnimator uses non-linear time interpolation, via the 38 * {@link AccelerateDecelerateInterpolator} class, which accelerates into and decelerates 39 * out of an animation. This behavior can be changed by calling 40 * {@link ValueAnimator#setInterpolator(TimeInterpolator)}.</p> 41 * 42 * <div class="special reference"> 43 * <h3>Developer Guides</h3> 44 * <p>For more information about animating with {@code ValueAnimator}, read the 45 * <a href="{@docRoot}guide/topics/graphics/prop-animation.html#value-animator">Property 46 * Animation</a> developer guide.</p> 47 * </div> 48 */ 49@SuppressWarnings("unchecked") 50public class ValueAnimator extends Animator { 51 52 /** 53 * Internal constants 54 */ 55 private static float sDurationScale = 1.0f; 56 57 /** 58 * Values used with internal variable mPlayingState to indicate the current state of an 59 * animation. 60 */ 61 static final int STOPPED = 0; // Not yet playing 62 static final int RUNNING = 1; // Playing normally 63 static final int SEEKED = 2; // Seeked to some time value 64 65 /** 66 * Internal variables 67 * NOTE: This object implements the clone() method, making a deep copy of any referenced 68 * objects. As other non-trivial fields are added to this class, make sure to add logic 69 * to clone() to make deep copies of them. 70 */ 71 72 // The first time that the animation's animateFrame() method is called. This time is used to 73 // determine elapsed time (and therefore the elapsed fraction) in subsequent calls 74 // to animateFrame() 75 long mStartTime; 76 77 /** 78 * Set when setCurrentPlayTime() is called. If negative, animation is not currently seeked 79 * to a value. 80 */ 81 long mSeekTime = -1; 82 83 /** 84 * Set on the next frame after pause() is called, used to calculate a new startTime 85 * or delayStartTime which allows the animator to continue from the point at which 86 * it was paused. If negative, has not yet been set. 87 */ 88 private long mPauseTime; 89 90 /** 91 * Set when an animator is resumed. This triggers logic in the next frame which 92 * actually resumes the animator. 93 */ 94 private boolean mResumed = false; 95 96 97 // The static sAnimationHandler processes the internal timing loop on which all animations 98 // are based 99 /** 100 * @hide 101 */ 102 protected static ThreadLocal<AnimationHandler> sAnimationHandler = 103 new ThreadLocal<AnimationHandler>(); 104 105 // The time interpolator to be used if none is set on the animation 106 private static final TimeInterpolator sDefaultInterpolator = 107 new AccelerateDecelerateInterpolator(); 108 109 /** 110 * Used to indicate whether the animation is currently playing in reverse. This causes the 111 * elapsed fraction to be inverted to calculate the appropriate values. 112 */ 113 private boolean mPlayingBackwards = false; 114 115 /** 116 * This variable tracks the current iteration that is playing. When mCurrentIteration exceeds the 117 * repeatCount (if repeatCount!=INFINITE), the animation ends 118 */ 119 private int mCurrentIteration = 0; 120 121 /** 122 * Tracks current elapsed/eased fraction, for querying in getAnimatedFraction(). 123 */ 124 private float mCurrentFraction = 0f; 125 126 /** 127 * Tracks whether a startDelay'd animation has begun playing through the startDelay. 128 */ 129 private boolean mStartedDelay = false; 130 131 /** 132 * Tracks the time at which the animation began playing through its startDelay. This is 133 * different from the mStartTime variable, which is used to track when the animation became 134 * active (which is when the startDelay expired and the animation was added to the active 135 * animations list). 136 */ 137 private long mDelayStartTime; 138 139 /** 140 * Flag that represents the current state of the animation. Used to figure out when to start 141 * an animation (if state == STOPPED). Also used to end an animation that 142 * has been cancel()'d or end()'d since the last animation frame. Possible values are 143 * STOPPED, RUNNING, SEEKED. 144 */ 145 int mPlayingState = STOPPED; 146 147 /** 148 * Additional playing state to indicate whether an animator has been start()'d. There is 149 * some lag between a call to start() and the first animation frame. We should still note 150 * that the animation has been started, even if it's first animation frame has not yet 151 * happened, and reflect that state in isRunning(). 152 * Note that delayed animations are different: they are not started until their first 153 * animation frame, which occurs after their delay elapses. 154 */ 155 private boolean mRunning = false; 156 157 /** 158 * Additional playing state to indicate whether an animator has been start()'d, whether or 159 * not there is a nonzero startDelay. 160 */ 161 private boolean mStarted = false; 162 163 /** 164 * Tracks whether we've notified listeners of the onAnimationStart() event. This can be 165 * complex to keep track of since we notify listeners at different times depending on 166 * startDelay and whether start() was called before end(). 167 */ 168 private boolean mStartListenersCalled = false; 169 170 /** 171 * Flag that denotes whether the animation is set up and ready to go. Used to 172 * set up animation that has not yet been started. 173 */ 174 boolean mInitialized = false; 175 176 // 177 // Backing variables 178 // 179 180 // How long the animation should last in ms 181 private long mDuration = (long)(300 * sDurationScale); 182 private long mUnscaledDuration = 300; 183 184 // The amount of time in ms to delay starting the animation after start() is called 185 private long mStartDelay = 0; 186 private long mUnscaledStartDelay = 0; 187 188 // The number of times the animation will repeat. The default is 0, which means the animation 189 // will play only once 190 private int mRepeatCount = 0; 191 192 /** 193 * The type of repetition that will occur when repeatMode is nonzero. RESTART means the 194 * animation will start from the beginning on every new cycle. REVERSE means the animation 195 * will reverse directions on each iteration. 196 */ 197 private int mRepeatMode = RESTART; 198 199 /** 200 * The time interpolator to be used. The elapsed fraction of the animation will be passed 201 * through this interpolator to calculate the interpolated fraction, which is then used to 202 * calculate the animated values. 203 */ 204 private TimeInterpolator mInterpolator = sDefaultInterpolator; 205 206 /** 207 * The set of listeners to be sent events through the life of an animation. 208 */ 209 private ArrayList<AnimatorUpdateListener> mUpdateListeners = null; 210 211 /** 212 * The property/value sets being animated. 213 */ 214 PropertyValuesHolder[] mValues; 215 216 /** 217 * A hashmap of the PropertyValuesHolder objects. This map is used to lookup animated values 218 * by property name during calls to getAnimatedValue(String). 219 */ 220 HashMap<String, PropertyValuesHolder> mValuesMap; 221 222 /** 223 * Public constants 224 */ 225 226 /** 227 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 228 * or a positive value, the animation restarts from the beginning. 229 */ 230 public static final int RESTART = 1; 231 /** 232 * When the animation reaches the end and <code>repeatCount</code> is INFINITE 233 * or a positive value, the animation reverses direction on every iteration. 234 */ 235 public static final int REVERSE = 2; 236 /** 237 * This value used used with the {@link #setRepeatCount(int)} property to repeat 238 * the animation indefinitely. 239 */ 240 public static final int INFINITE = -1; 241 242 243 /** 244 * @hide 245 */ 246 public static void setDurationScale(float durationScale) { 247 sDurationScale = durationScale; 248 } 249 250 /** 251 * @hide 252 */ 253 public static float getDurationScale() { 254 return sDurationScale; 255 } 256 257 /** 258 * Creates a new ValueAnimator object. This default constructor is primarily for 259 * use internally; the factory methods which take parameters are more generally 260 * useful. 261 */ 262 public ValueAnimator() { 263 } 264 265 /** 266 * Constructs and returns a ValueAnimator that animates between int values. A single 267 * value implies that that value is the one being animated to. However, this is not typically 268 * useful in a ValueAnimator object because there is no way for the object to determine the 269 * starting value for the animation (unlike ObjectAnimator, which can derive that value 270 * from the target object and property being animated). Therefore, there should typically 271 * be two or more values. 272 * 273 * @param values A set of values that the animation will animate between over time. 274 * @return A ValueAnimator object that is set up to animate between the given values. 275 */ 276 public static ValueAnimator ofInt(int... values) { 277 ValueAnimator anim = new ValueAnimator(); 278 anim.setIntValues(values); 279 return anim; 280 } 281 282 /** 283 * Constructs and returns a ValueAnimator that animates between color values. A single 284 * value implies that that value is the one being animated to. However, this is not typically 285 * useful in a ValueAnimator object because there is no way for the object to determine the 286 * starting value for the animation (unlike ObjectAnimator, which can derive that value 287 * from the target object and property being animated). Therefore, there should typically 288 * be two or more values. 289 * 290 * @param values A set of values that the animation will animate between over time. 291 * @return A ValueAnimator object that is set up to animate between the given values. 292 */ 293 public static ValueAnimator ofArgb(int... values) { 294 ValueAnimator anim = new ValueAnimator(); 295 anim.setIntValues(values); 296 anim.setEvaluator(ArgbEvaluator.getInstance()); 297 return anim; 298 } 299 300 /** 301 * Constructs and returns a ValueAnimator that animates between float 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 ofFloat(float... values) { 312 ValueAnimator anim = new ValueAnimator(); 313 anim.setFloatValues(values); 314 return anim; 315 } 316 317 /** 318 * Constructs and returns a ValueAnimator that animates between the values 319 * specified in the PropertyValuesHolder objects. 320 * 321 * @param values A set of PropertyValuesHolder objects whose values will be animated 322 * between over time. 323 * @return A ValueAnimator object that is set up to animate between the given values. 324 */ 325 public static ValueAnimator ofPropertyValuesHolder(PropertyValuesHolder... values) { 326 ValueAnimator anim = new ValueAnimator(); 327 anim.setValues(values); 328 return anim; 329 } 330 /** 331 * Constructs and returns a ValueAnimator that animates between Object values. A single 332 * value implies that that value is the one being animated to. However, this is not typically 333 * useful in a ValueAnimator object because there is no way for the object to determine the 334 * starting value for the animation (unlike ObjectAnimator, which can derive that value 335 * from the target object and property being animated). Therefore, there should typically 336 * be two or more values. 337 * 338 * <p>Since ValueAnimator does not know how to animate between arbitrary Objects, this 339 * factory method also takes a TypeEvaluator object that the ValueAnimator will use 340 * to perform that interpolation. 341 * 342 * @param evaluator A TypeEvaluator that will be called on each animation frame to 343 * provide the ncessry interpolation between the Object values to derive the animated 344 * value. 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 */ 348 public static ValueAnimator ofObject(TypeEvaluator evaluator, Object... values) { 349 ValueAnimator anim = new ValueAnimator(); 350 anim.setObjectValues(values); 351 anim.setEvaluator(evaluator); 352 return anim; 353 } 354 355 /** 356 * Sets int values that will be animated between. A single 357 * value implies that that value is the one being animated to. However, this is not typically 358 * useful in a ValueAnimator object because there is no way for the object to determine the 359 * starting value for the animation (unlike ObjectAnimator, which can derive that value 360 * from the target object and property being animated). Therefore, there should typically 361 * be two or more values. 362 * 363 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 364 * than one PropertyValuesHolder object, this method will set the values for the first 365 * of those objects.</p> 366 * 367 * @param values A set of values that the animation will animate between over time. 368 */ 369 public void setIntValues(int... values) { 370 if (values == null || values.length == 0) { 371 return; 372 } 373 if (mValues == null || mValues.length == 0) { 374 setValues(PropertyValuesHolder.ofInt("", values)); 375 } else { 376 PropertyValuesHolder valuesHolder = mValues[0]; 377 valuesHolder.setIntValues(values); 378 } 379 // New property/values/target should cause re-initialization prior to starting 380 mInitialized = false; 381 } 382 383 /** 384 * Sets float values that will be animated between. A single 385 * value implies that that value is the one being animated to. However, this is not typically 386 * useful in a ValueAnimator object because there is no way for the object to determine the 387 * starting value for the animation (unlike ObjectAnimator, which can derive that value 388 * from the target object and property being animated). Therefore, there should typically 389 * be two or more values. 390 * 391 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 392 * than one PropertyValuesHolder object, this method will set the values for the first 393 * of those objects.</p> 394 * 395 * @param values A set of values that the animation will animate between over time. 396 */ 397 public void setFloatValues(float... values) { 398 if (values == null || values.length == 0) { 399 return; 400 } 401 if (mValues == null || mValues.length == 0) { 402 setValues(PropertyValuesHolder.ofFloat("", values)); 403 } else { 404 PropertyValuesHolder valuesHolder = mValues[0]; 405 valuesHolder.setFloatValues(values); 406 } 407 // New property/values/target should cause re-initialization prior to starting 408 mInitialized = false; 409 } 410 411 /** 412 * Sets the values to animate between for this animation. A single 413 * value implies that that value is the one being animated to. However, this is not typically 414 * useful in a ValueAnimator object because there is no way for the object to determine the 415 * starting value for the animation (unlike ObjectAnimator, which can derive that value 416 * from the target object and property being animated). Therefore, there should typically 417 * be two or more values. 418 * 419 * <p>If there are already multiple sets of values defined for this ValueAnimator via more 420 * than one PropertyValuesHolder object, this method will set the values for the first 421 * of those objects.</p> 422 * 423 * <p>There should be a TypeEvaluator set on the ValueAnimator that knows how to interpolate 424 * between these value objects. ValueAnimator only knows how to interpolate between the 425 * primitive types specified in the other setValues() methods.</p> 426 * 427 * @param values The set of values to animate between. 428 */ 429 public void setObjectValues(Object... values) { 430 if (values == null || values.length == 0) { 431 return; 432 } 433 if (mValues == null || mValues.length == 0) { 434 setValues(PropertyValuesHolder.ofObject("", null, values)); 435 } else { 436 PropertyValuesHolder valuesHolder = mValues[0]; 437 valuesHolder.setObjectValues(values); 438 } 439 // New property/values/target should cause re-initialization prior to starting 440 mInitialized = false; 441 } 442 443 /** 444 * Sets the values, per property, being animated between. This function is called internally 445 * by the constructors of ValueAnimator that take a list of values. But a ValueAnimator can 446 * be constructed without values and this method can be called to set the values manually 447 * instead. 448 * 449 * @param values The set of values, per property, being animated between. 450 */ 451 public void setValues(PropertyValuesHolder... values) { 452 int numValues = values.length; 453 mValues = values; 454 mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 455 for (int i = 0; i < numValues; ++i) { 456 PropertyValuesHolder valuesHolder = values[i]; 457 mValuesMap.put(valuesHolder.getPropertyName(), valuesHolder); 458 } 459 // New property/values/target should cause re-initialization prior to starting 460 mInitialized = false; 461 } 462 463 /** 464 * Returns the values that this ValueAnimator animates between. These values are stored in 465 * PropertyValuesHolder objects, even if the ValueAnimator was created with a simple list 466 * of value objects instead. 467 * 468 * @return PropertyValuesHolder[] An array of PropertyValuesHolder objects which hold the 469 * values, per property, that define the animation. 470 */ 471 public PropertyValuesHolder[] getValues() { 472 return mValues; 473 } 474 475 /** 476 * This function is called immediately before processing the first animation 477 * frame of an animation. If there is a nonzero <code>startDelay</code>, the 478 * function is called after that delay ends. 479 * It takes care of the final initialization steps for the 480 * animation. 481 * 482 * <p>Overrides of this method should call the superclass method to ensure 483 * that internal mechanisms for the animation are set up correctly.</p> 484 */ 485 void initAnimation() { 486 if (!mInitialized) { 487 int numValues = mValues.length; 488 for (int i = 0; i < numValues; ++i) { 489 mValues[i].init(); 490 } 491 mInitialized = true; 492 } 493 } 494 495 496 /** 497 * Sets the length of the animation. The default duration is 300 milliseconds. 498 * 499 * @param duration The length of the animation, in milliseconds. This value cannot 500 * be negative. 501 * @return ValueAnimator The object called with setDuration(). This return 502 * value makes it easier to compose statements together that construct and then set the 503 * duration, as in <code>ValueAnimator.ofInt(0, 10).setDuration(500).start()</code>. 504 */ 505 public ValueAnimator setDuration(long duration) { 506 if (duration < 0) { 507 throw new IllegalArgumentException("Animators cannot have negative duration: " + 508 duration); 509 } 510 mUnscaledDuration = duration; 511 mDuration = (long)(duration * sDurationScale); 512 return this; 513 } 514 515 /** 516 * Gets the length of the animation. The default duration is 300 milliseconds. 517 * 518 * @return The length of the animation, in milliseconds. 519 */ 520 public long getDuration() { 521 return mUnscaledDuration; 522 } 523 524 /** 525 * Sets the position of the animation to the specified point in time. This time should 526 * be between 0 and the total duration of the animation, including any repetition. If 527 * the animation has not yet been started, then it will not advance forward after it is 528 * set to this time; it will simply set the time to this value and perform any appropriate 529 * actions based on that time. If the animation is already running, then setCurrentPlayTime() 530 * will set the current playing time to this value and continue playing from that point. 531 * 532 * @param playTime The time, in milliseconds, to which the animation is advanced or rewound. 533 */ 534 public void setCurrentPlayTime(long playTime) { 535 initAnimation(); 536 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 537 if (mPlayingState != RUNNING) { 538 mSeekTime = playTime; 539 mPlayingState = SEEKED; 540 } 541 mStartTime = currentTime - playTime; 542 doAnimationFrame(currentTime); 543 } 544 545 /** 546 * Gets the current position of the animation in time, which is equal to the current 547 * time minus the time that the animation started. An animation that is not yet started will 548 * return a value of zero. 549 * 550 * @return The current position in time of the animation. 551 */ 552 public long getCurrentPlayTime() { 553 if (!mInitialized || mPlayingState == STOPPED) { 554 return 0; 555 } 556 return AnimationUtils.currentAnimationTimeMillis() - mStartTime; 557 } 558 559 /** 560 * This custom, static handler handles the timing pulse that is shared by 561 * all active animations. This approach ensures that the setting of animation 562 * values will happen on the UI thread and that all animations will share 563 * the same times for calculating their values, which makes synchronizing 564 * animations possible. 565 * 566 * The handler uses the Choreographer for executing periodic callbacks. 567 * 568 * @hide 569 */ 570 @SuppressWarnings("unchecked") 571 protected static class AnimationHandler implements Runnable { 572 // The per-thread list of all active animations 573 /** @hide */ 574 protected final ArrayList<ValueAnimator> mAnimations = new ArrayList<ValueAnimator>(); 575 576 // Used in doAnimationFrame() to avoid concurrent modifications of mAnimations 577 private final ArrayList<ValueAnimator> mTmpAnimations = new ArrayList<ValueAnimator>(); 578 579 // The per-thread set of animations to be started on the next animation frame 580 /** @hide */ 581 protected final ArrayList<ValueAnimator> mPendingAnimations = new ArrayList<ValueAnimator>(); 582 583 /** 584 * Internal per-thread collections used to avoid set collisions as animations start and end 585 * while being processed. 586 * @hide 587 */ 588 protected final ArrayList<ValueAnimator> mDelayedAnims = new ArrayList<ValueAnimator>(); 589 private final ArrayList<ValueAnimator> mEndingAnims = new ArrayList<ValueAnimator>(); 590 private final ArrayList<ValueAnimator> mReadyAnims = new ArrayList<ValueAnimator>(); 591 592 private final Choreographer mChoreographer; 593 private boolean mAnimationScheduled; 594 595 private AnimationHandler() { 596 mChoreographer = Choreographer.getInstance(); 597 } 598 599 /** 600 * Start animating on the next frame. 601 */ 602 public void start() { 603 scheduleAnimation(); 604 } 605 606 private void doAnimationFrame(long frameTime) { 607 // mPendingAnimations holds any animations that have requested to be started 608 // We're going to clear mPendingAnimations, but starting animation may 609 // cause more to be added to the pending list (for example, if one animation 610 // starting triggers another starting). So we loop until mPendingAnimations 611 // is empty. 612 while (mPendingAnimations.size() > 0) { 613 ArrayList<ValueAnimator> pendingCopy = 614 (ArrayList<ValueAnimator>) mPendingAnimations.clone(); 615 mPendingAnimations.clear(); 616 int count = pendingCopy.size(); 617 for (int i = 0; i < count; ++i) { 618 ValueAnimator anim = pendingCopy.get(i); 619 // If the animation has a startDelay, place it on the delayed list 620 if (anim.mStartDelay == 0) { 621 anim.startAnimation(this); 622 } else { 623 mDelayedAnims.add(anim); 624 } 625 } 626 } 627 // Next, process animations currently sitting on the delayed queue, adding 628 // them to the active animations if they are ready 629 int numDelayedAnims = mDelayedAnims.size(); 630 for (int i = 0; i < numDelayedAnims; ++i) { 631 ValueAnimator anim = mDelayedAnims.get(i); 632 if (anim.delayedAnimationFrame(frameTime)) { 633 mReadyAnims.add(anim); 634 } 635 } 636 int numReadyAnims = mReadyAnims.size(); 637 if (numReadyAnims > 0) { 638 for (int i = 0; i < numReadyAnims; ++i) { 639 ValueAnimator anim = mReadyAnims.get(i); 640 anim.startAnimation(this); 641 anim.mRunning = true; 642 mDelayedAnims.remove(anim); 643 } 644 mReadyAnims.clear(); 645 } 646 647 // Now process all active animations. The return value from animationFrame() 648 // tells the handler whether it should now be ended 649 int numAnims = mAnimations.size(); 650 for (int i = 0; i < numAnims; ++i) { 651 mTmpAnimations.add(mAnimations.get(i)); 652 } 653 for (int i = 0; i < numAnims; ++i) { 654 ValueAnimator anim = mTmpAnimations.get(i); 655 if (mAnimations.contains(anim) && anim.doAnimationFrame(frameTime)) { 656 mEndingAnims.add(anim); 657 } 658 } 659 mTmpAnimations.clear(); 660 if (mEndingAnims.size() > 0) { 661 for (int i = 0; i < mEndingAnims.size(); ++i) { 662 mEndingAnims.get(i).endAnimation(this); 663 } 664 mEndingAnims.clear(); 665 } 666 667 // If there are still active or delayed animations, schedule a future call to 668 // onAnimate to process the next frame of the animations. 669 if (!mAnimations.isEmpty() || !mDelayedAnims.isEmpty()) { 670 scheduleAnimation(); 671 } 672 } 673 674 // Called by the Choreographer. 675 @Override 676 public void run() { 677 mAnimationScheduled = false; 678 doAnimationFrame(mChoreographer.getFrameTime()); 679 } 680 681 private void scheduleAnimation() { 682 if (!mAnimationScheduled) { 683 mChoreographer.postCallback(Choreographer.CALLBACK_ANIMATION, this, null); 684 mAnimationScheduled = true; 685 } 686 } 687 } 688 689 /** 690 * The amount of time, in milliseconds, to delay starting the animation after 691 * {@link #start()} is called. 692 * 693 * @return the number of milliseconds to delay running the animation 694 */ 695 public long getStartDelay() { 696 return mUnscaledStartDelay; 697 } 698 699 /** 700 * The amount of time, in milliseconds, to delay starting the animation after 701 * {@link #start()} is called. 702 703 * @param startDelay The amount of the delay, in milliseconds 704 */ 705 public void setStartDelay(long startDelay) { 706 this.mStartDelay = (long)(startDelay * sDurationScale); 707 mUnscaledStartDelay = startDelay; 708 } 709 710 /** 711 * The amount of time, in milliseconds, between each frame of the animation. This is a 712 * requested time that the animation will attempt to honor, but the actual delay between 713 * frames may be different, depending on system load and capabilities. This is a static 714 * function because the same delay will be applied to all animations, since they are all 715 * run off of a single timing loop. 716 * 717 * The frame delay may be ignored when the animation system uses an external timing 718 * source, such as the display refresh rate (vsync), to govern animations. 719 * 720 * @return the requested time between frames, in milliseconds 721 */ 722 public static long getFrameDelay() { 723 return Choreographer.getFrameDelay(); 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 * @param frameDelay the requested time between frames, in milliseconds 737 */ 738 public static void setFrameDelay(long frameDelay) { 739 Choreographer.setFrameDelay(frameDelay); 740 } 741 742 /** 743 * The most recent value calculated by this <code>ValueAnimator</code> when there is just one 744 * property being animated. This value is only sensible while the animation is running. The main 745 * purpose for this read-only property is to retrieve the value from the <code>ValueAnimator</code> 746 * during a call to {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 747 * is called during each animation frame, immediately after the value is calculated. 748 * 749 * @return animatedValue The value most recently calculated by this <code>ValueAnimator</code> for 750 * the single property being animated. If there are several properties being animated 751 * (specified by several PropertyValuesHolder objects in the constructor), this function 752 * returns the animated value for the first of those objects. 753 */ 754 public Object getAnimatedValue() { 755 if (mValues != null && mValues.length > 0) { 756 return mValues[0].getAnimatedValue(); 757 } 758 // Shouldn't get here; should always have values unless ValueAnimator was set up wrong 759 return null; 760 } 761 762 /** 763 * The most recent value calculated by this <code>ValueAnimator</code> for <code>propertyName</code>. 764 * The main purpose for this read-only property is to retrieve the value from the 765 * <code>ValueAnimator</code> during a call to 766 * {@link AnimatorUpdateListener#onAnimationUpdate(ValueAnimator)}, which 767 * is called during each animation frame, immediately after the value is calculated. 768 * 769 * @return animatedValue The value most recently calculated for the named property 770 * by this <code>ValueAnimator</code>. 771 */ 772 public Object getAnimatedValue(String propertyName) { 773 PropertyValuesHolder valuesHolder = mValuesMap.get(propertyName); 774 if (valuesHolder != null) { 775 return valuesHolder.getAnimatedValue(); 776 } else { 777 // At least avoid crashing if called with bogus propertyName 778 return null; 779 } 780 } 781 782 /** 783 * Sets how many times the animation should be repeated. If the repeat 784 * count is 0, the animation is never repeated. If the repeat count is 785 * greater than 0 or {@link #INFINITE}, the repeat mode will be taken 786 * into account. The repeat count is 0 by default. 787 * 788 * @param value the number of times the animation should be repeated 789 */ 790 public void setRepeatCount(int value) { 791 mRepeatCount = value; 792 } 793 /** 794 * Defines how many times the animation should repeat. The default value 795 * is 0. 796 * 797 * @return the number of times the animation should repeat, or {@link #INFINITE} 798 */ 799 public int getRepeatCount() { 800 return mRepeatCount; 801 } 802 803 /** 804 * Defines what this animation should do when it reaches the end. This 805 * setting is applied only when the repeat count is either greater than 806 * 0 or {@link #INFINITE}. Defaults to {@link #RESTART}. 807 * 808 * @param value {@link #RESTART} or {@link #REVERSE} 809 */ 810 public void setRepeatMode(int value) { 811 mRepeatMode = value; 812 } 813 814 /** 815 * Defines what this animation should do when it reaches the end. 816 * 817 * @return either one of {@link #REVERSE} or {@link #RESTART} 818 */ 819 public int getRepeatMode() { 820 return mRepeatMode; 821 } 822 823 /** 824 * Adds a listener to the set of listeners that are sent update events through the life of 825 * an animation. This method is called on all listeners for every frame of the animation, 826 * after the values for the animation have been calculated. 827 * 828 * @param listener the listener to be added to the current set of listeners for this animation. 829 */ 830 public void addUpdateListener(AnimatorUpdateListener listener) { 831 if (mUpdateListeners == null) { 832 mUpdateListeners = new ArrayList<AnimatorUpdateListener>(); 833 } 834 mUpdateListeners.add(listener); 835 } 836 837 /** 838 * Removes all listeners from the set listening to frame updates for this animation. 839 */ 840 public void removeAllUpdateListeners() { 841 if (mUpdateListeners == null) { 842 return; 843 } 844 mUpdateListeners.clear(); 845 mUpdateListeners = null; 846 } 847 848 /** 849 * Removes a listener from the set listening to frame updates for this animation. 850 * 851 * @param listener the listener to be removed from the current set of update listeners 852 * for this animation. 853 */ 854 public void removeUpdateListener(AnimatorUpdateListener listener) { 855 if (mUpdateListeners == null) { 856 return; 857 } 858 mUpdateListeners.remove(listener); 859 if (mUpdateListeners.size() == 0) { 860 mUpdateListeners = null; 861 } 862 } 863 864 865 /** 866 * The time interpolator used in calculating the elapsed fraction of this animation. The 867 * interpolator determines whether the animation runs with linear or non-linear motion, 868 * such as acceleration and deceleration. The default value is 869 * {@link android.view.animation.AccelerateDecelerateInterpolator} 870 * 871 * @param value the interpolator to be used by this animation. A value of <code>null</code> 872 * will result in linear interpolation. 873 */ 874 @Override 875 public void setInterpolator(TimeInterpolator value) { 876 if (value != null) { 877 mInterpolator = value; 878 } else { 879 mInterpolator = new LinearInterpolator(); 880 } 881 } 882 883 /** 884 * Returns the timing interpolator that this ValueAnimator uses. 885 * 886 * @return The timing interpolator for this ValueAnimator. 887 */ 888 @Override 889 public TimeInterpolator getInterpolator() { 890 return mInterpolator; 891 } 892 893 /** 894 * The type evaluator to be used when calculating the animated values of this animation. 895 * The system will automatically assign a float or int evaluator based on the type 896 * of <code>startValue</code> and <code>endValue</code> in the constructor. But if these values 897 * are not one of these primitive types, or if different evaluation is desired (such as is 898 * necessary with int values that represent colors), a custom evaluator needs to be assigned. 899 * For example, when running an animation on color values, the {@link ArgbEvaluator} 900 * should be used to get correct RGB color interpolation. 901 * 902 * <p>If this ValueAnimator has only one set of values being animated between, this evaluator 903 * will be used for that set. If there are several sets of values being animated, which is 904 * the case if PropertyValuesHolder objects were set on the ValueAnimator, then the evaluator 905 * is assigned just to the first PropertyValuesHolder object.</p> 906 * 907 * @param value the evaluator to be used this animation 908 */ 909 public void setEvaluator(TypeEvaluator value) { 910 if (value != null && mValues != null && mValues.length > 0) { 911 mValues[0].setEvaluator(value); 912 } 913 } 914 915 private void notifyStartListeners() { 916 if (mListeners != null && !mStartListenersCalled) { 917 ArrayList<AnimatorListener> tmpListeners = 918 (ArrayList<AnimatorListener>) mListeners.clone(); 919 int numListeners = tmpListeners.size(); 920 for (int i = 0; i < numListeners; ++i) { 921 tmpListeners.get(i).onAnimationStart(this); 922 } 923 } 924 mStartListenersCalled = true; 925 } 926 927 /** 928 * Start the animation playing. This version of start() takes a boolean flag that indicates 929 * whether the animation should play in reverse. The flag is usually false, but may be set 930 * to true if called from the reverse() method. 931 * 932 * <p>The animation started by calling this method will be run on the thread that called 933 * this method. This thread should have a Looper on it (a runtime exception will be thrown if 934 * this is not the case). Also, if the animation will animate 935 * properties of objects in the view hierarchy, then the calling thread should be the UI 936 * thread for that view hierarchy.</p> 937 * 938 * @param playBackwards Whether the ValueAnimator should start playing in reverse. 939 */ 940 private void start(boolean playBackwards) { 941 if (Looper.myLooper() == null) { 942 throw new AndroidRuntimeException("Animators may only be run on Looper threads"); 943 } 944 mPlayingBackwards = playBackwards; 945 mCurrentIteration = 0; 946 mPlayingState = STOPPED; 947 mStarted = true; 948 mStartedDelay = false; 949 mPaused = false; 950 AnimationHandler animationHandler = getOrCreateAnimationHandler(); 951 animationHandler.mPendingAnimations.add(this); 952 if (mStartDelay == 0) { 953 // This sets the initial value of the animation, prior to actually starting it running 954 setCurrentPlayTime(0); 955 mPlayingState = STOPPED; 956 mRunning = true; 957 notifyStartListeners(); 958 } 959 animationHandler.start(); 960 } 961 962 @Override 963 public void start() { 964 start(false); 965 } 966 967 @Override 968 public void cancel() { 969 // Only cancel if the animation is actually running or has been started and is about 970 // to run 971 AnimationHandler handler = getOrCreateAnimationHandler(); 972 if (mPlayingState != STOPPED 973 || handler.mPendingAnimations.contains(this) 974 || handler.mDelayedAnims.contains(this)) { 975 // Only notify listeners if the animator has actually started 976 if ((mStarted || mRunning) && mListeners != null) { 977 if (!mRunning) { 978 // If it's not yet running, then start listeners weren't called. Call them now. 979 notifyStartListeners(); 980 } 981 ArrayList<AnimatorListener> tmpListeners = 982 (ArrayList<AnimatorListener>) mListeners.clone(); 983 for (AnimatorListener listener : tmpListeners) { 984 listener.onAnimationCancel(this); 985 } 986 } 987 endAnimation(handler); 988 } 989 } 990 991 @Override 992 public void end() { 993 AnimationHandler handler = getOrCreateAnimationHandler(); 994 if (!handler.mAnimations.contains(this) && !handler.mPendingAnimations.contains(this)) { 995 // Special case if the animation has not yet started; get it ready for ending 996 mStartedDelay = false; 997 startAnimation(handler); 998 mStarted = true; 999 } else if (!mInitialized) { 1000 initAnimation(); 1001 } 1002 animateValue(mPlayingBackwards ? 0f : 1f); 1003 endAnimation(handler); 1004 } 1005 1006 @Override 1007 public void resume() { 1008 if (mPaused) { 1009 mResumed = true; 1010 } 1011 super.resume(); 1012 } 1013 1014 @Override 1015 public void pause() { 1016 boolean previouslyPaused = mPaused; 1017 super.pause(); 1018 if (!previouslyPaused && mPaused) { 1019 mPauseTime = -1; 1020 mResumed = false; 1021 } 1022 } 1023 1024 @Override 1025 public boolean isRunning() { 1026 return (mPlayingState == RUNNING || mRunning); 1027 } 1028 1029 @Override 1030 public boolean isStarted() { 1031 return mStarted; 1032 } 1033 1034 /** 1035 * Plays the ValueAnimator in reverse. If the animation is already running, 1036 * it will stop itself and play backwards from the point reached when reverse was called. 1037 * If the animation is not currently running, then it will start from the end and 1038 * play backwards. This behavior is only set for the current animation; future playing 1039 * of the animation will use the default behavior of playing forward. 1040 */ 1041 public void reverse() { 1042 mPlayingBackwards = !mPlayingBackwards; 1043 if (mPlayingState == RUNNING) { 1044 long currentTime = AnimationUtils.currentAnimationTimeMillis(); 1045 long currentPlayTime = currentTime - mStartTime; 1046 long timeLeft = mDuration - currentPlayTime; 1047 mStartTime = currentTime - timeLeft; 1048 } else if (mStarted) { 1049 end(); 1050 } else { 1051 start(true); 1052 } 1053 } 1054 1055 /** 1056 * Called internally to end an animation by removing it from the animations list. Must be 1057 * called on the UI thread. 1058 */ 1059 private void endAnimation(AnimationHandler handler) { 1060 handler.mAnimations.remove(this); 1061 handler.mPendingAnimations.remove(this); 1062 handler.mDelayedAnims.remove(this); 1063 mPlayingState = STOPPED; 1064 mPaused = false; 1065 if ((mStarted || mRunning) && mListeners != null) { 1066 if (!mRunning) { 1067 // If it's not yet running, then start listeners weren't called. Call them now. 1068 notifyStartListeners(); 1069 } 1070 ArrayList<AnimatorListener> tmpListeners = 1071 (ArrayList<AnimatorListener>) mListeners.clone(); 1072 int numListeners = tmpListeners.size(); 1073 for (int i = 0; i < numListeners; ++i) { 1074 tmpListeners.get(i).onAnimationEnd(this); 1075 } 1076 } 1077 mRunning = false; 1078 mStarted = false; 1079 mStartListenersCalled = false; 1080 mPlayingBackwards = false; 1081 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1082 Trace.asyncTraceEnd(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1083 System.identityHashCode(this)); 1084 } 1085 } 1086 1087 /** 1088 * Called internally to start an animation by adding it to the active animations list. Must be 1089 * called on the UI thread. 1090 */ 1091 private void startAnimation(AnimationHandler handler) { 1092 if (Trace.isTagEnabled(Trace.TRACE_TAG_VIEW)) { 1093 Trace.asyncTraceBegin(Trace.TRACE_TAG_VIEW, getNameForTrace(), 1094 System.identityHashCode(this)); 1095 } 1096 initAnimation(); 1097 handler.mAnimations.add(this); 1098 if (mStartDelay > 0 && mListeners != null) { 1099 // Listeners were already notified in start() if startDelay is 0; this is 1100 // just for delayed animations 1101 notifyStartListeners(); 1102 } 1103 } 1104 1105 /** 1106 * Returns the name of this animator for debugging purposes. 1107 */ 1108 String getNameForTrace() { 1109 return "animator"; 1110 } 1111 1112 1113 /** 1114 * Internal function called to process an animation frame on an animation that is currently 1115 * sleeping through its <code>startDelay</code> phase. The return value indicates whether it 1116 * should be woken up and put on the active animations queue. 1117 * 1118 * @param currentTime The current animation time, used to calculate whether the animation 1119 * has exceeded its <code>startDelay</code> and should be started. 1120 * @return True if the animation's <code>startDelay</code> has been exceeded and the animation 1121 * should be added to the set of active animations. 1122 */ 1123 private boolean delayedAnimationFrame(long currentTime) { 1124 if (!mStartedDelay) { 1125 mStartedDelay = true; 1126 mDelayStartTime = currentTime; 1127 } else { 1128 if (mPaused) { 1129 if (mPauseTime < 0) { 1130 mPauseTime = currentTime; 1131 } 1132 return false; 1133 } else if (mResumed) { 1134 mResumed = false; 1135 if (mPauseTime > 0) { 1136 // Offset by the duration that the animation was paused 1137 mDelayStartTime += (currentTime - mPauseTime); 1138 } 1139 } 1140 long deltaTime = currentTime - mDelayStartTime; 1141 if (deltaTime > mStartDelay) { 1142 // startDelay ended - start the anim and record the 1143 // mStartTime appropriately 1144 mStartTime = currentTime - (deltaTime - mStartDelay); 1145 mPlayingState = RUNNING; 1146 return true; 1147 } 1148 } 1149 return false; 1150 } 1151 1152 /** 1153 * This internal function processes a single animation frame for a given animation. The 1154 * currentTime parameter is the timing pulse sent by the handler, used to calculate the 1155 * elapsed duration, and therefore 1156 * the elapsed fraction, of the animation. The return value indicates whether the animation 1157 * should be ended (which happens when the elapsed time of the animation exceeds the 1158 * animation's duration, including the repeatCount). 1159 * 1160 * @param currentTime The current time, as tracked by the static timing handler 1161 * @return true if the animation's duration, including any repetitions due to 1162 * <code>repeatCount</code>, has been exceeded and the animation should be ended. 1163 */ 1164 boolean animationFrame(long currentTime) { 1165 boolean done = false; 1166 switch (mPlayingState) { 1167 case RUNNING: 1168 case SEEKED: 1169 float fraction = mDuration > 0 ? (float)(currentTime - mStartTime) / mDuration : 1f; 1170 if (fraction >= 1f) { 1171 if (mCurrentIteration < mRepeatCount || mRepeatCount == INFINITE) { 1172 // Time to repeat 1173 if (mListeners != null) { 1174 int numListeners = mListeners.size(); 1175 for (int i = 0; i < numListeners; ++i) { 1176 mListeners.get(i).onAnimationRepeat(this); 1177 } 1178 } 1179 if (mRepeatMode == REVERSE) { 1180 mPlayingBackwards = !mPlayingBackwards; 1181 } 1182 mCurrentIteration += (int)fraction; 1183 fraction = fraction % 1f; 1184 mStartTime += mDuration; 1185 } else { 1186 done = true; 1187 fraction = Math.min(fraction, 1.0f); 1188 } 1189 } 1190 if (mPlayingBackwards) { 1191 fraction = 1f - fraction; 1192 } 1193 animateValue(fraction); 1194 break; 1195 } 1196 1197 return done; 1198 } 1199 1200 /** 1201 * Processes a frame of the animation, adjusting the start time if needed. 1202 * 1203 * @param frameTime The frame time. 1204 * @return true if the animation has ended. 1205 */ 1206 final boolean doAnimationFrame(long frameTime) { 1207 if (mPlayingState == STOPPED) { 1208 mPlayingState = RUNNING; 1209 if (mSeekTime < 0) { 1210 mStartTime = frameTime; 1211 } else { 1212 mStartTime = frameTime - mSeekTime; 1213 // Now that we're playing, reset the seek time 1214 mSeekTime = -1; 1215 } 1216 } 1217 if (mPaused) { 1218 if (mPauseTime < 0) { 1219 mPauseTime = frameTime; 1220 } 1221 return false; 1222 } else if (mResumed) { 1223 mResumed = false; 1224 if (mPauseTime > 0) { 1225 // Offset by the duration that the animation was paused 1226 mStartTime += (frameTime - mPauseTime); 1227 } 1228 } 1229 // The frame time might be before the start time during the first frame of 1230 // an animation. The "current time" must always be on or after the start 1231 // time to avoid animating frames at negative time intervals. In practice, this 1232 // is very rare and only happens when seeking backwards. 1233 final long currentTime = Math.max(frameTime, mStartTime); 1234 return animationFrame(currentTime); 1235 } 1236 1237 /** 1238 * Returns the current animation fraction, which is the elapsed/interpolated fraction used in 1239 * the most recent frame update on the animation. 1240 * 1241 * @return Elapsed/interpolated fraction of the animation. 1242 */ 1243 public float getAnimatedFraction() { 1244 return mCurrentFraction; 1245 } 1246 1247 /** 1248 * This method is called with the elapsed fraction of the animation during every 1249 * animation frame. This function turns the elapsed fraction into an interpolated fraction 1250 * and then into an animated value (from the evaluator. The function is called mostly during 1251 * animation updates, but it is also called when the <code>end()</code> 1252 * function is called, to set the final value on the property. 1253 * 1254 * <p>Overrides of this method must call the superclass to perform the calculation 1255 * of the animated value.</p> 1256 * 1257 * @param fraction The elapsed fraction of the animation. 1258 */ 1259 void animateValue(float fraction) { 1260 fraction = mInterpolator.getInterpolation(fraction); 1261 mCurrentFraction = fraction; 1262 int numValues = mValues.length; 1263 for (int i = 0; i < numValues; ++i) { 1264 mValues[i].calculateValue(fraction); 1265 } 1266 if (mUpdateListeners != null) { 1267 int numListeners = mUpdateListeners.size(); 1268 for (int i = 0; i < numListeners; ++i) { 1269 mUpdateListeners.get(i).onAnimationUpdate(this); 1270 } 1271 } 1272 } 1273 1274 @Override 1275 public ValueAnimator clone() { 1276 final ValueAnimator anim = (ValueAnimator) super.clone(); 1277 if (mUpdateListeners != null) { 1278 ArrayList<AnimatorUpdateListener> oldListeners = mUpdateListeners; 1279 anim.mUpdateListeners = new ArrayList<AnimatorUpdateListener>(); 1280 int numListeners = oldListeners.size(); 1281 for (int i = 0; i < numListeners; ++i) { 1282 anim.mUpdateListeners.add(oldListeners.get(i)); 1283 } 1284 } 1285 anim.mSeekTime = -1; 1286 anim.mPlayingBackwards = false; 1287 anim.mCurrentIteration = 0; 1288 anim.mInitialized = false; 1289 anim.mPlayingState = STOPPED; 1290 anim.mStartedDelay = false; 1291 PropertyValuesHolder[] oldValues = mValues; 1292 if (oldValues != null) { 1293 int numValues = oldValues.length; 1294 anim.mValues = new PropertyValuesHolder[numValues]; 1295 anim.mValuesMap = new HashMap<String, PropertyValuesHolder>(numValues); 1296 for (int i = 0; i < numValues; ++i) { 1297 PropertyValuesHolder newValuesHolder = oldValues[i].clone(); 1298 anim.mValues[i] = newValuesHolder; 1299 anim.mValuesMap.put(newValuesHolder.getPropertyName(), newValuesHolder); 1300 } 1301 } 1302 return anim; 1303 } 1304 1305 /** 1306 * Implementors of this interface can add themselves as update listeners 1307 * to an <code>ValueAnimator</code> instance to receive callbacks on every animation 1308 * frame, after the current frame's values have been calculated for that 1309 * <code>ValueAnimator</code>. 1310 */ 1311 public static interface AnimatorUpdateListener { 1312 /** 1313 * <p>Notifies the occurrence of another frame of the animation.</p> 1314 * 1315 * @param animation The animation which was repeated. 1316 */ 1317 void onAnimationUpdate(ValueAnimator animation); 1318 1319 } 1320 1321 /** 1322 * Return the number of animations currently running. 1323 * 1324 * Used by StrictMode internally to annotate violations. 1325 * May be called on arbitrary threads! 1326 * 1327 * @hide 1328 */ 1329 public static int getCurrentAnimationsCount() { 1330 AnimationHandler handler = sAnimationHandler.get(); 1331 return handler != null ? handler.mAnimations.size() : 0; 1332 } 1333 1334 /** 1335 * Clear all animations on this thread, without canceling or ending them. 1336 * This should be used with caution. 1337 * 1338 * @hide 1339 */ 1340 public static void clearAllAnimations() { 1341 AnimationHandler handler = sAnimationHandler.get(); 1342 if (handler != null) { 1343 handler.mAnimations.clear(); 1344 handler.mPendingAnimations.clear(); 1345 handler.mDelayedAnims.clear(); 1346 } 1347 } 1348 1349 private static AnimationHandler getOrCreateAnimationHandler() { 1350 AnimationHandler handler = sAnimationHandler.get(); 1351 if (handler == null) { 1352 handler = new AnimationHandler(); 1353 sAnimationHandler.set(handler); 1354 } 1355 return handler; 1356 } 1357 1358 @Override 1359 public String toString() { 1360 String returnVal = "ValueAnimator@" + Integer.toHexString(hashCode()); 1361 if (mValues != null) { 1362 for (int i = 0; i < mValues.length; ++i) { 1363 returnVal += "\n " + mValues[i].toString(); 1364 } 1365 } 1366 return returnVal; 1367 } 1368} 1369