Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2019 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 com.android.systemui.util.animation |
| 18 | |
| 19 | import android.os.Looper |
| 20 | import android.util.ArrayMap |
| 21 | import android.util.Log |
| 22 | import android.view.View |
| 23 | import androidx.dynamicanimation.animation.DynamicAnimation |
| 24 | import androidx.dynamicanimation.animation.FlingAnimation |
| 25 | import androidx.dynamicanimation.animation.FloatPropertyCompat |
| 26 | import androidx.dynamicanimation.animation.SpringAnimation |
| 27 | import androidx.dynamicanimation.animation.SpringForce |
| 28 | import com.android.systemui.util.animation.PhysicsAnimator.Companion.getInstance |
| 29 | import java.util.WeakHashMap |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 30 | import kotlin.math.abs |
| 31 | import kotlin.math.max |
| 32 | import kotlin.math.min |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 33 | |
| 34 | /** |
| 35 | * Extension function for all objects which will return a PhysicsAnimator instance for that object. |
| 36 | */ |
| 37 | val <T : View> T.physicsAnimator: PhysicsAnimator<T> get() { return getInstance(this) } |
| 38 | |
| 39 | private const val TAG = "PhysicsAnimator" |
| 40 | |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 41 | private val UNSET = -Float.MAX_VALUE |
| 42 | |
| 43 | /** |
| 44 | * [FlingAnimation] multiplies the friction set via [FlingAnimation.setFriction] by 4.2f, which is |
| 45 | * where this number comes from. We use it in [PhysicsAnimator.flingThenSpring] to calculate the |
| 46 | * minimum velocity for a fling to reach a certain value, given the fling's friction. |
| 47 | */ |
| 48 | private const val FLING_FRICTION_SCALAR_MULTIPLIER = 4.2f |
| 49 | |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 50 | typealias EndAction = () -> Unit |
| 51 | |
| 52 | /** A map of Property -> AnimationUpdate, which is provided to update listeners on each frame. */ |
| 53 | typealias UpdateMap<T> = |
| 54 | ArrayMap<FloatPropertyCompat<in T>, PhysicsAnimator.AnimationUpdate> |
| 55 | |
| 56 | /** |
| 57 | * Map of the animators associated with a given object. This ensures that only one animator |
| 58 | * per object exists. |
| 59 | */ |
| 60 | internal val animators = WeakHashMap<Any, PhysicsAnimator<*>>() |
| 61 | |
| 62 | /** |
| 63 | * Default spring configuration to use for animations where stiffness and/or damping ratio |
| 64 | * were not provided. |
| 65 | */ |
| 66 | private val defaultSpring = PhysicsAnimator.SpringConfig( |
| 67 | SpringForce.STIFFNESS_MEDIUM, |
| 68 | SpringForce.DAMPING_RATIO_MEDIUM_BOUNCY) |
| 69 | |
| 70 | /** Default fling configuration to use for animations where friction was not provided. */ |
| 71 | private val defaultFling = PhysicsAnimator.FlingConfig( |
| 72 | friction = 1f, min = -Float.MAX_VALUE, max = Float.MAX_VALUE) |
| 73 | |
| 74 | /** Whether to log helpful debug information about animations. */ |
| 75 | private var verboseLogging = false |
| 76 | |
| 77 | /** |
| 78 | * Animator that uses physics-based animations to animate properties on views and objects. Physics |
| 79 | * animations use real-world physical concepts, such as momentum and mass, to realistically simulate |
| 80 | * motion. PhysicsAnimator is heavily inspired by [android.view.ViewPropertyAnimator], and |
| 81 | * also uses the builder pattern to configure and start animations. |
| 82 | * |
| 83 | * The physics animations are backed by [DynamicAnimation]. |
| 84 | * |
| 85 | * @param T The type of the object being animated. |
| 86 | */ |
| 87 | class PhysicsAnimator<T> private constructor (val target: T) { |
| 88 | |
| 89 | /** Data class for representing animation frame updates. */ |
| 90 | data class AnimationUpdate(val value: Float, val velocity: Float) |
| 91 | |
| 92 | /** [DynamicAnimation] instances for the given properties. */ |
| 93 | private val springAnimations = ArrayMap<FloatPropertyCompat<in T>, SpringAnimation>() |
| 94 | private val flingAnimations = ArrayMap<FloatPropertyCompat<in T>, FlingAnimation>() |
| 95 | |
| 96 | /** |
| 97 | * Spring and fling configurations for the properties to be animated on the target. We'll |
| 98 | * configure and start the DynamicAnimations for these properties according to the provided |
| 99 | * configurations. |
| 100 | */ |
| 101 | private val springConfigs = ArrayMap<FloatPropertyCompat<in T>, SpringConfig>() |
| 102 | private val flingConfigs = ArrayMap<FloatPropertyCompat<in T>, FlingConfig>() |
| 103 | |
| 104 | /** |
| 105 | * Animation listeners for the animation. These will be notified when each property animation |
| 106 | * updates or ends. |
| 107 | */ |
| 108 | private val updateListeners = ArrayList<UpdateListener<T>>() |
| 109 | private val endListeners = ArrayList<EndListener<T>>() |
| 110 | |
| 111 | /** End actions to run when all animations have completed. */ |
| 112 | private val endActions = ArrayList<EndAction>() |
| 113 | |
| 114 | /** |
| 115 | * Internal listeners that respond to DynamicAnimations updating and ending, and dispatch to |
| 116 | * the listeners provided via [addUpdateListener] and [addEndListener]. This allows us to add |
| 117 | * just one permanent update and end listener to the DynamicAnimations. |
| 118 | */ |
| 119 | internal var internalListeners = ArrayList<InternalListener>() |
| 120 | |
| 121 | /** |
| 122 | * Action to run when [start] is called. This can be changed by |
| 123 | * [PhysicsAnimatorTestUtils.prepareForTest] to enable animators to run under test and provide |
| 124 | * helpful test utilities. |
| 125 | */ |
| 126 | internal var startAction: () -> Unit = ::startInternal |
| 127 | |
| 128 | /** |
Joshua Tsuji | 959ac76 | 2020-02-13 03:21:56 -0500 | [diff] [blame] | 129 | * Action to run when [cancel] is called. This can be changed by |
| 130 | * [PhysicsAnimatorTestUtils.prepareForTest] to cancel animations from the main thread, which |
| 131 | * is required. |
| 132 | */ |
| 133 | internal var cancelAction: (Set<FloatPropertyCompat<in T>>) -> Unit = ::cancelInternal |
| 134 | |
| 135 | /** |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 136 | * Springs a property to the given value, using the provided configuration settings. |
| 137 | * |
| 138 | * Springs are used when you know the exact value to which you want to animate. They can be |
| 139 | * configured with a start velocity (typically used when the spring is initiated by a touch |
| 140 | * event), but this velocity will be realistically attenuated as forces are applied to move the |
| 141 | * property towards the end value. |
| 142 | * |
| 143 | * If you find yourself repeating the same stiffness and damping ratios many times, consider |
| 144 | * storing a single [SpringConfig] instance and passing that in instead of individual values. |
| 145 | * |
| 146 | * @param property The property to spring to the given value. The property must be an instance |
| 147 | * of FloatPropertyCompat<? super T>. For example, if this is a |
| 148 | * PhysicsAnimator<FrameLayout>, you can use a FloatPropertyCompat<FrameLayout>, as |
| 149 | * well as a FloatPropertyCompat<ViewGroup>, and so on. |
| 150 | * @param toPosition The value to spring the given property to. |
| 151 | * @param startVelocity The initial velocity to use for the animation. |
| 152 | * @param stiffness The stiffness to use for the spring. Higher stiffness values result in |
| 153 | * faster animations, while lower stiffness means a slower animation. Reasonable values for |
| 154 | * low, medium, and high stiffness can be found as constants in [SpringForce]. |
| 155 | * @param dampingRatio The damping ratio (bounciness) to use for the spring. Higher values |
| 156 | * result in a less 'springy' animation, while lower values allow the animation to bounce |
| 157 | * back and forth for a longer time after reaching the final position. Reasonable values for |
| 158 | * low, medium, and high damping can be found in [SpringForce]. |
| 159 | */ |
| 160 | fun spring( |
| 161 | property: FloatPropertyCompat<in T>, |
| 162 | toPosition: Float, |
| 163 | startVelocity: Float = 0f, |
| 164 | stiffness: Float = defaultSpring.stiffness, |
| 165 | dampingRatio: Float = defaultSpring.dampingRatio |
| 166 | ): PhysicsAnimator<T> { |
| 167 | if (verboseLogging) { |
| 168 | Log.d(TAG, "Springing ${getReadablePropertyName(property)} to $toPosition.") |
| 169 | } |
| 170 | |
| 171 | springConfigs[property] = |
| 172 | SpringConfig(stiffness, dampingRatio, startVelocity, toPosition) |
| 173 | return this |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Springs a property to a given value using the provided start velocity and configuration |
| 178 | * options. |
| 179 | * |
| 180 | * @see spring |
| 181 | */ |
| 182 | fun spring( |
| 183 | property: FloatPropertyCompat<in T>, |
| 184 | toPosition: Float, |
| 185 | startVelocity: Float, |
| 186 | config: SpringConfig = defaultSpring |
| 187 | ): PhysicsAnimator<T> { |
| 188 | return spring( |
| 189 | property, toPosition, startVelocity, config.stiffness, config.dampingRatio) |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Springs a property to a given value using the provided configuration options, and a start |
| 194 | * velocity of 0f. |
| 195 | * |
| 196 | * @see spring |
| 197 | */ |
| 198 | fun spring( |
| 199 | property: FloatPropertyCompat<in T>, |
| 200 | toPosition: Float, |
| 201 | config: SpringConfig = defaultSpring |
| 202 | ): PhysicsAnimator<T> { |
| 203 | return spring(property, toPosition, 0f, config) |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * Flings a property using the given start velocity, using a [FlingAnimation] configured using |
| 208 | * the provided configuration settings. |
| 209 | * |
| 210 | * Flings are used when you have a start velocity, and want the property value to realistically |
| 211 | * decrease as friction is applied until the velocity reaches zero. Flings do not have a |
| 212 | * deterministic end value. If you are attempting to animate to a specific end value, use |
| 213 | * [spring]. |
| 214 | * |
| 215 | * If you find yourself repeating the same friction/min/max values, consider storing a single |
| 216 | * [FlingConfig] and passing that in instead. |
| 217 | * |
| 218 | * @param property The property to fling using the given start velocity. |
| 219 | * @param startVelocity The start velocity (in pixels per second) with which to start the fling. |
| 220 | * @param friction Friction value applied to slow down the animation over time. Higher values |
| 221 | * will more quickly slow the animation. Typical friction values range from 1f to 10f. |
| 222 | * @param min The minimum value allowed for the animation. If this value is reached, the |
| 223 | * animation will end abruptly. |
| 224 | * @param max The maximum value allowed for the animation. If this value is reached, the |
| 225 | * animation will end abruptly. |
| 226 | */ |
| 227 | fun fling( |
| 228 | property: FloatPropertyCompat<in T>, |
| 229 | startVelocity: Float, |
| 230 | friction: Float = defaultFling.friction, |
| 231 | min: Float = defaultFling.min, |
| 232 | max: Float = defaultFling.max |
| 233 | ): PhysicsAnimator<T> { |
| 234 | if (verboseLogging) { |
| 235 | Log.d(TAG, "Flinging ${getReadablePropertyName(property)} " + |
| 236 | "with velocity $startVelocity.") |
| 237 | } |
| 238 | |
| 239 | flingConfigs[property] = FlingConfig(friction, min, max, startVelocity) |
| 240 | return this |
| 241 | } |
| 242 | |
| 243 | /** |
| 244 | * Flings a property using the given start velocity, using a [FlingAnimation] configured using |
| 245 | * the provided configuration settings. |
| 246 | * |
| 247 | * @see fling |
| 248 | */ |
| 249 | fun fling( |
| 250 | property: FloatPropertyCompat<in T>, |
| 251 | startVelocity: Float, |
| 252 | config: FlingConfig = defaultFling |
| 253 | ): PhysicsAnimator<T> { |
| 254 | return fling(property, startVelocity, config.friction, config.min, config.max) |
| 255 | } |
| 256 | |
| 257 | /** |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 258 | * Flings a property using the given start velocity. If the fling animation reaches the min/max |
| 259 | * bounds (from the [flingConfig]) with velocity remaining, it'll overshoot it and spring back. |
| 260 | * |
| 261 | * If the object is already out of the fling bounds, it will immediately spring back within |
| 262 | * bounds. |
| 263 | * |
| 264 | * This is useful for animating objects that are bounded by constraints such as screen edges, |
| 265 | * since otherwise the fling animation would end abruptly upon reaching the min/max bounds. |
| 266 | * |
| 267 | * @param property The property to animate. |
| 268 | * @param startVelocity The velocity, in pixels/second, with which to start the fling. If the |
| 269 | * object is already outside the fling bounds, this velocity will be used as the start velocity |
| 270 | * of the spring that will spring it back within bounds. |
| 271 | * @param flingMustReachMinOrMax If true, the fling animation is guaranteed to reach either its |
| 272 | * minimum bound (if [startVelocity] is negative) or maximum bound (if it's positive). The |
| 273 | * animator will use startVelocity if it's sufficient, or add more velocity if necessary. This |
| 274 | * is useful when fling's deceleration-based physics are preferable to the acceleration-based |
| 275 | * forces used by springs - typically, when you're allowing the user to move an object somewhere |
| 276 | * on the screen, but it needs to be along an edge. |
| 277 | * @param flingConfig The configuration to use for the fling portion of the animation. |
| 278 | * @param springConfig The configuration to use for the spring portion of the animation. |
| 279 | */ |
| 280 | @JvmOverloads |
| 281 | fun flingThenSpring( |
| 282 | property: FloatPropertyCompat<in T>, |
| 283 | startVelocity: Float, |
| 284 | flingConfig: FlingConfig, |
| 285 | springConfig: SpringConfig, |
| 286 | flingMustReachMinOrMax: Boolean = false |
| 287 | ): PhysicsAnimator<T> { |
| 288 | val flingConfigCopy = flingConfig.copy() |
| 289 | val springConfigCopy = springConfig.copy() |
| 290 | val toAtLeast = if (startVelocity < 0) flingConfig.min else flingConfig.max |
| 291 | |
| 292 | // If the fling needs to reach min/max, calculate the velocity required to do so and use |
| 293 | // that if the provided start velocity is not sufficient. |
| 294 | if (flingMustReachMinOrMax && |
| 295 | toAtLeast != -Float.MAX_VALUE && toAtLeast != Float.MAX_VALUE) { |
| 296 | val distanceToDestination = toAtLeast - property.getValue(target) |
| 297 | |
| 298 | // The minimum velocity required for the fling to end up at the given destination, |
| 299 | // taking the provided fling friction value. |
| 300 | val velocityToReachDestination = distanceToDestination * |
| 301 | (flingConfig.friction * FLING_FRICTION_SCALAR_MULTIPLIER) |
| 302 | |
Joshua Tsuji | a265399 | 2020-01-15 14:28:38 -0500 | [diff] [blame] | 303 | // If there's distance to cover, and the provided velocity is moving in the correct |
| 304 | // direction, ensure that the velocity is high enough to reach the destination. |
| 305 | // Otherwise, just use startVelocity - this means that the fling is at or out of bounds. |
| 306 | // The fling will immediately end and a spring will bring the object back into bounds |
| 307 | // with this startVelocity. |
| 308 | flingConfigCopy.startVelocity = when { |
| 309 | distanceToDestination > 0f && startVelocity >= 0f -> |
| 310 | max(velocityToReachDestination, startVelocity) |
| 311 | distanceToDestination < 0f && startVelocity <= 0f -> |
| 312 | min(velocityToReachDestination, startVelocity) |
| 313 | else -> startVelocity |
| 314 | } |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 315 | |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 316 | springConfigCopy.finalPosition = toAtLeast |
| 317 | } else { |
| 318 | flingConfigCopy.startVelocity = startVelocity |
| 319 | } |
| 320 | |
| 321 | flingConfigs[property] = flingConfigCopy |
| 322 | springConfigs[property] = springConfigCopy |
| 323 | return this |
| 324 | } |
| 325 | |
| 326 | /** |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 327 | * Adds a listener that will be called whenever any property on the animated object is updated. |
| 328 | * This will be called on every animation frame, with the current value of the animated object |
| 329 | * and the new property values. |
| 330 | */ |
| 331 | fun addUpdateListener(listener: UpdateListener<T>): PhysicsAnimator<T> { |
| 332 | updateListeners.add(listener) |
| 333 | return this |
| 334 | } |
| 335 | |
| 336 | /** |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 337 | * Adds a listener that will be called when a property stops animating. This is useful if |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 338 | * you care about a specific property ending, or want to use the end value/end velocity from a |
| 339 | * particular property's animation. If you just want to run an action when all property |
| 340 | * animations have ended, use [withEndActions]. |
| 341 | */ |
| 342 | fun addEndListener(listener: EndListener<T>): PhysicsAnimator<T> { |
| 343 | endListeners.add(listener) |
| 344 | return this |
| 345 | } |
| 346 | |
| 347 | /** |
| 348 | * Adds end actions that will be run sequentially when animations for every property involved in |
| 349 | * this specific animation have ended (unless they were explicitly canceled). For example, if |
| 350 | * you call: |
| 351 | * |
| 352 | * animator |
| 353 | * .spring(TRANSLATION_X, ...) |
| 354 | * .spring(TRANSLATION_Y, ...) |
| 355 | * .withEndAction(action) |
| 356 | * .start() |
| 357 | * |
| 358 | * 'action' will be run when both TRANSLATION_X and TRANSLATION_Y end. |
| 359 | * |
| 360 | * Other properties may still be animating, if those animations were not started in the same |
| 361 | * call. For example: |
| 362 | * |
| 363 | * animator |
| 364 | * .spring(ALPHA, ...) |
| 365 | * .start() |
| 366 | * |
| 367 | * animator |
| 368 | * .spring(TRANSLATION_X, ...) |
| 369 | * .spring(TRANSLATION_Y, ...) |
| 370 | * .withEndAction(action) |
| 371 | * .start() |
| 372 | * |
| 373 | * 'action' will still be run as soon as TRANSLATION_X and TRANSLATION_Y end, even if ALPHA is |
| 374 | * still animating. |
| 375 | * |
| 376 | * If you want to run actions as soon as a subset of property animations have ended, you want |
| 377 | * access to the animation's end value/velocity, or you want to run these actions even if the |
| 378 | * animation is explicitly canceled, use [addEndListener]. End listeners have an allEnded param, |
| 379 | * which indicates that all relevant animations have ended. |
| 380 | */ |
Joshua Tsuji | bace224 | 2020-01-14 15:51:48 -0500 | [diff] [blame] | 381 | fun withEndActions(vararg endActions: EndAction?): PhysicsAnimator<T> { |
| 382 | this.endActions.addAll(endActions.filterNotNull()) |
| 383 | return this |
| 384 | } |
| 385 | |
| 386 | /** |
| 387 | * Helper overload so that callers from Java can use Runnables or method references as end |
| 388 | * actions without having to explicitly return Unit. |
| 389 | */ |
| 390 | fun withEndActions(vararg endActions: Runnable?): PhysicsAnimator<T> { |
| 391 | this.endActions.addAll(endActions.filterNotNull().map { it::run }) |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 392 | return this |
| 393 | } |
| 394 | |
| 395 | /** Starts the animations! */ |
| 396 | fun start() { |
| 397 | startAction() |
| 398 | } |
| 399 | |
| 400 | /** |
| 401 | * Starts the animations for real! This is typically called immediately by [start] unless this |
| 402 | * animator is under test. |
| 403 | */ |
| 404 | internal fun startInternal() { |
| 405 | if (!Looper.getMainLooper().isCurrentThread) { |
| 406 | Log.e(TAG, "Animations can only be started on the main thread. If you are seeing " + |
| 407 | "this message in a test, call PhysicsAnimatorTestUtils#prepareForTest in " + |
| 408 | "your test setup.") |
| 409 | } |
| 410 | |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 411 | // Functions that will actually start the animations. These are run after we build and add |
| 412 | // the InternalListener, since some animations might update/end immediately and we don't |
| 413 | // want to miss those updates. |
| 414 | val animationStartActions = ArrayList<() -> Unit>() |
| 415 | |
| 416 | for (animatedProperty in getAnimatedProperties()) { |
| 417 | val flingConfig = flingConfigs[animatedProperty] |
| 418 | val springConfig = springConfigs[animatedProperty] |
| 419 | |
| 420 | // The property's current value on the object. |
| 421 | val currentValue = animatedProperty.getValue(target) |
| 422 | |
| 423 | // Start by checking for a fling configuration. If one is present, we're either flinging |
| 424 | // or flinging-then-springing. Either way, we'll want to start the fling first. |
| 425 | if (flingConfig != null) { |
| 426 | animationStartActions.add { |
| 427 | // When the animation is starting, adjust the min/max bounds to include the |
| 428 | // current value of the property, if necessary. This is required to allow a |
| 429 | // fling to bring an out-of-bounds object back into bounds. For example, if an |
| 430 | // object was dragged halfway off the left side of the screen, but then flung to |
| 431 | // the right, we don't want the animation to end instantly just because the |
| 432 | // object started out of bounds. If the fling is in the direction that would |
| 433 | // take it farther out of bounds, it will end instantly as expected. |
| 434 | flingConfig.apply { |
| 435 | min = min(currentValue, this.min) |
| 436 | max = max(currentValue, this.max) |
| 437 | } |
| 438 | |
Joshua Tsuji | 959ac76 | 2020-02-13 03:21:56 -0500 | [diff] [blame] | 439 | // Flings can't be updated to a new position while maintaining velocity, because |
| 440 | // we're using the explicitly provided start velocity. Cancel any flings (or |
| 441 | // springs) on this property before flinging. |
| 442 | cancel(animatedProperty) |
| 443 | |
| 444 | // Apply the configuration and start the animation. |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 445 | getFlingAnimation(animatedProperty) |
| 446 | .also { flingConfig.applyToAnimation(it) } |
| 447 | .start() |
| 448 | } |
| 449 | } |
| 450 | |
| 451 | // Check for a spring configuration. If one is present, we're either springing, or |
| 452 | // flinging-then-springing. |
| 453 | if (springConfig != null) { |
| 454 | |
| 455 | // If there is no corresponding fling config, we're only springing. |
| 456 | if (flingConfig == null) { |
| 457 | // Apply the configuration and start the animation. |
| 458 | val springAnim = getSpringAnimation(animatedProperty) |
| 459 | springConfig.applyToAnimation(springAnim) |
| 460 | animationStartActions.add(springAnim::start) |
| 461 | } else { |
| 462 | // If there's a corresponding fling config, we're flinging-then-springing. Save |
| 463 | // the fling's original bounds so we can spring to them when the fling ends. |
| 464 | val flingMin = flingConfig.min |
| 465 | val flingMax = flingConfig.max |
| 466 | |
| 467 | // Add an end listener that will start the spring when the fling ends. |
| 468 | endListeners.add(0, object : EndListener<T> { |
| 469 | override fun onAnimationEnd( |
| 470 | target: T, |
| 471 | property: FloatPropertyCompat<in T>, |
| 472 | wasFling: Boolean, |
| 473 | canceled: Boolean, |
| 474 | finalValue: Float, |
| 475 | finalVelocity: Float, |
| 476 | allRelevantPropertyAnimsEnded: Boolean |
| 477 | ) { |
| 478 | // If this isn't the relevant property, it wasn't a fling, or the fling |
| 479 | // was explicitly cancelled, don't spring. |
| 480 | if (property != animatedProperty || !wasFling || canceled) { |
| 481 | return |
| 482 | } |
| 483 | |
| 484 | val endedWithVelocity = abs(finalVelocity) > 0 |
| 485 | |
| 486 | // If the object was out of bounds when the fling animation started, it |
| 487 | // will immediately end. In that case, we'll spring it back in bounds. |
| 488 | val endedOutOfBounds = finalValue !in flingMin..flingMax |
| 489 | |
| 490 | // If the fling ended either out of bounds or with remaining velocity, |
| 491 | // it's time to spring. |
| 492 | if (endedWithVelocity || endedOutOfBounds) { |
| 493 | springConfig.startVelocity = finalVelocity |
| 494 | |
| 495 | // If the spring's final position isn't set, this is a |
| 496 | // flingThenSpring where flingMustReachMinOrMax was false. We'll |
| 497 | // need to set the spring's final position here. |
| 498 | if (springConfig.finalPosition == UNSET) { |
| 499 | if (endedWithVelocity) { |
| 500 | // If the fling ended with negative velocity, that means it |
| 501 | // hit the min bound, so spring to that bound (and vice |
| 502 | // versa). |
| 503 | springConfig.finalPosition = |
| 504 | if (finalVelocity < 0) flingMin else flingMax |
| 505 | } else if (endedOutOfBounds) { |
| 506 | // If the fling ended out of bounds, spring it to the |
| 507 | // nearest bound. |
| 508 | springConfig.finalPosition = |
| 509 | if (finalValue < flingMin) flingMin else flingMax |
| 510 | } |
| 511 | } |
| 512 | |
| 513 | // Apply the configuration and start the spring animation. |
| 514 | getSpringAnimation(animatedProperty) |
| 515 | .also { springConfig.applyToAnimation(it) } |
| 516 | .start() |
| 517 | } |
| 518 | } |
| 519 | }) |
| 520 | } |
| 521 | } |
| 522 | } |
| 523 | |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 524 | // Add an internal listener that will dispatch animation events to the provided listeners. |
| 525 | internalListeners.add(InternalListener( |
| 526 | getAnimatedProperties(), |
| 527 | ArrayList(updateListeners), |
| 528 | ArrayList(endListeners), |
| 529 | ArrayList(endActions))) |
| 530 | |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 531 | // Actually start the DynamicAnimations. This is delayed until after the InternalListener is |
| 532 | // constructed and added so that we don't miss the end listener firing for any animations |
| 533 | // that immediately end. |
| 534 | animationStartActions.forEach { it.invoke() } |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 535 | |
| 536 | clearAnimator() |
| 537 | } |
| 538 | |
| 539 | /** Clear the animator's builder variables. */ |
| 540 | private fun clearAnimator() { |
| 541 | springConfigs.clear() |
| 542 | flingConfigs.clear() |
| 543 | |
| 544 | updateListeners.clear() |
| 545 | endListeners.clear() |
| 546 | endActions.clear() |
| 547 | } |
| 548 | |
| 549 | /** Retrieves a spring animation for the given property, building one if needed. */ |
| 550 | private fun getSpringAnimation(property: FloatPropertyCompat<in T>): SpringAnimation { |
| 551 | return springAnimations.getOrPut( |
| 552 | property, |
| 553 | { configureDynamicAnimation(SpringAnimation(target, property), property) |
| 554 | as SpringAnimation }) |
| 555 | } |
| 556 | |
| 557 | /** Retrieves a fling animation for the given property, building one if needed. */ |
| 558 | private fun getFlingAnimation(property: FloatPropertyCompat<in T>): FlingAnimation { |
| 559 | return flingAnimations.getOrPut( |
| 560 | property, |
| 561 | { configureDynamicAnimation(FlingAnimation(target, property), property) |
| 562 | as FlingAnimation }) |
| 563 | } |
| 564 | |
| 565 | /** |
| 566 | * Adds update and end listeners to the DynamicAnimation which will dispatch to the internal |
| 567 | * listeners. |
| 568 | */ |
| 569 | private fun configureDynamicAnimation( |
| 570 | anim: DynamicAnimation<*>, |
| 571 | property: FloatPropertyCompat<in T> |
| 572 | ): DynamicAnimation<*> { |
| 573 | anim.addUpdateListener { _, value, velocity -> |
| 574 | for (i in 0 until internalListeners.size) { |
| 575 | internalListeners[i].onInternalAnimationUpdate(property, value, velocity) |
| 576 | } |
| 577 | } |
| 578 | anim.addEndListener { _, canceled, value, velocity -> |
| 579 | internalListeners.removeAll { |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 580 | it.onInternalAnimationEnd( |
| 581 | property, canceled, value, velocity, anim is FlingAnimation) |
| 582 | } |
| 583 | } |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 584 | return anim |
| 585 | } |
| 586 | |
| 587 | /** |
| 588 | * Internal listener class that receives updates from DynamicAnimation listeners, and dispatches |
| 589 | * them to the appropriate update/end listeners. This class is also aware of which properties |
| 590 | * were being animated when the end listeners were passed in, so that we can provide the |
| 591 | * appropriate value for allEnded to [EndListener.onAnimationEnd]. |
| 592 | */ |
| 593 | internal inner class InternalListener constructor( |
| 594 | private var properties: Set<FloatPropertyCompat<in T>>, |
| 595 | private var updateListeners: List<UpdateListener<T>>, |
| 596 | private var endListeners: List<EndListener<T>>, |
| 597 | private var endActions: List<EndAction> |
| 598 | ) { |
| 599 | |
| 600 | /** The number of properties whose animations haven't ended. */ |
| 601 | private var numPropertiesAnimating = properties.size |
| 602 | |
| 603 | /** |
| 604 | * Update values that haven't yet been dispatched because not all property animations have |
| 605 | * updated yet. |
| 606 | */ |
| 607 | private val undispatchedUpdates = |
| 608 | ArrayMap<FloatPropertyCompat<in T>, AnimationUpdate>() |
| 609 | |
| 610 | /** Called when a DynamicAnimation updates. */ |
| 611 | internal fun onInternalAnimationUpdate( |
| 612 | property: FloatPropertyCompat<in T>, |
| 613 | value: Float, |
| 614 | velocity: Float |
| 615 | ) { |
| 616 | |
| 617 | // If this property animation isn't relevant to this listener, ignore it. |
| 618 | if (!properties.contains(property)) { |
| 619 | return |
| 620 | } |
| 621 | |
| 622 | undispatchedUpdates[property] = AnimationUpdate(value, velocity) |
| 623 | maybeDispatchUpdates() |
| 624 | } |
| 625 | |
| 626 | /** |
| 627 | * Called when a DynamicAnimation ends. |
| 628 | * |
| 629 | * @return True if this listener should be removed from the list of internal listeners, so |
| 630 | * it no longer receives updates from DynamicAnimations. |
| 631 | */ |
| 632 | internal fun onInternalAnimationEnd( |
| 633 | property: FloatPropertyCompat<in T>, |
| 634 | canceled: Boolean, |
| 635 | finalValue: Float, |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 636 | finalVelocity: Float, |
| 637 | isFling: Boolean |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 638 | ): Boolean { |
| 639 | |
| 640 | // If this property animation isn't relevant to this listener, ignore it. |
| 641 | if (!properties.contains(property)) { |
| 642 | return false |
| 643 | } |
| 644 | |
| 645 | // Dispatch updates if we have one for each property. |
| 646 | numPropertiesAnimating-- |
| 647 | maybeDispatchUpdates() |
| 648 | |
| 649 | // If we didn't have an update for each property, dispatch the update for the ending |
| 650 | // property. This guarantees that an update isn't sent for this property *after* we call |
| 651 | // onAnimationEnd for that property. |
| 652 | if (undispatchedUpdates.contains(property)) { |
| 653 | updateListeners.forEach { updateListener -> |
| 654 | updateListener.onAnimationUpdateForProperty( |
| 655 | target, |
| 656 | UpdateMap<T>().also { it[property] = undispatchedUpdates[property] }) |
| 657 | } |
| 658 | |
| 659 | undispatchedUpdates.remove(property) |
| 660 | } |
| 661 | |
| 662 | val allEnded = !arePropertiesAnimating(properties) |
| 663 | endListeners.forEach { |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 664 | it.onAnimationEnd( |
| 665 | target, property, isFling, canceled, finalValue, finalVelocity, |
| 666 | allEnded) |
| 667 | |
| 668 | // Check that the end listener didn't restart this property's animation. |
| 669 | if (isPropertyAnimating(property)) { |
| 670 | return false |
| 671 | } |
| 672 | } |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 673 | |
| 674 | // If all of the animations that this listener cares about have ended, run the end |
| 675 | // actions unless the animation was canceled. |
| 676 | if (allEnded && !canceled) { |
| 677 | endActions.forEach { it() } |
| 678 | } |
| 679 | |
| 680 | return allEnded |
| 681 | } |
| 682 | |
| 683 | /** |
| 684 | * Dispatch undispatched values if we've received an update from each of the animating |
| 685 | * properties. |
| 686 | */ |
| 687 | private fun maybeDispatchUpdates() { |
| 688 | if (undispatchedUpdates.size >= numPropertiesAnimating && |
| 689 | undispatchedUpdates.size > 0) { |
| 690 | updateListeners.forEach { |
| 691 | it.onAnimationUpdateForProperty(target, ArrayMap(undispatchedUpdates)) |
| 692 | } |
| 693 | |
| 694 | undispatchedUpdates.clear() |
| 695 | } |
| 696 | } |
| 697 | } |
| 698 | |
| 699 | /** Return true if any animations are running on the object. */ |
| 700 | fun isRunning(): Boolean { |
| 701 | return arePropertiesAnimating(springAnimations.keys.union(flingAnimations.keys)) |
| 702 | } |
| 703 | |
| 704 | /** Returns whether the given property is animating. */ |
| 705 | fun isPropertyAnimating(property: FloatPropertyCompat<in T>): Boolean { |
Joshua Tsuji | bdb6b20 | 2020-01-08 14:29:02 -0500 | [diff] [blame] | 706 | return springAnimations[property]?.isRunning ?: false || |
| 707 | flingAnimations[property]?.isRunning ?: false |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 708 | } |
| 709 | |
| 710 | /** Returns whether any of the given properties are animating. */ |
| 711 | fun arePropertiesAnimating(properties: Set<FloatPropertyCompat<in T>>): Boolean { |
| 712 | return properties.any { isPropertyAnimating(it) } |
| 713 | } |
| 714 | |
| 715 | /** Return the set of properties that will begin animating upon calling [start]. */ |
| 716 | internal fun getAnimatedProperties(): Set<FloatPropertyCompat<in T>> { |
| 717 | return springConfigs.keys.union(flingConfigs.keys) |
| 718 | } |
| 719 | |
Joshua Tsuji | 959ac76 | 2020-02-13 03:21:56 -0500 | [diff] [blame] | 720 | /** |
| 721 | * Cancels the given properties. This is typically called immediately by [cancel], unless this |
| 722 | * animator is under test. |
| 723 | */ |
| 724 | internal fun cancelInternal(properties: Set<FloatPropertyCompat<in T>>) { |
| 725 | for (property in properties) { |
| 726 | flingAnimations[property]?.cancel() |
| 727 | springAnimations[property]?.cancel() |
| 728 | } |
| 729 | } |
| 730 | |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 731 | /** Cancels all in progress animations on all properties. */ |
| 732 | fun cancel() { |
Joshua Tsuji | 959ac76 | 2020-02-13 03:21:56 -0500 | [diff] [blame] | 733 | cancelAction(flingAnimations.keys) |
| 734 | cancelAction(springAnimations.keys) |
| 735 | } |
| 736 | |
| 737 | /** Cancels in progress animations on the provided properties only. */ |
| 738 | fun cancel(vararg properties: FloatPropertyCompat<in T>) { |
| 739 | cancelAction(properties.toSet()) |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 740 | } |
| 741 | |
| 742 | /** |
| 743 | * Container object for spring animation configuration settings. This allows you to store |
| 744 | * default stiffness and damping ratio values in a single configuration object, which you can |
| 745 | * pass to [spring]. |
| 746 | */ |
| 747 | data class SpringConfig internal constructor( |
| 748 | internal var stiffness: Float, |
| 749 | internal var dampingRatio: Float, |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 750 | internal var startVelocity: Float = 0f, |
| 751 | internal var finalPosition: Float = UNSET |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 752 | ) { |
| 753 | |
| 754 | constructor() : |
| 755 | this(defaultSpring.stiffness, defaultSpring.dampingRatio) |
| 756 | |
| 757 | constructor(stiffness: Float, dampingRatio: Float) : |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 758 | this(stiffness = stiffness, dampingRatio = dampingRatio, startVelocity = 0f) |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 759 | |
| 760 | /** Apply these configuration settings to the given SpringAnimation. */ |
| 761 | internal fun applyToAnimation(anim: SpringAnimation) { |
| 762 | val springForce = anim.spring ?: SpringForce() |
| 763 | anim.spring = springForce.apply { |
| 764 | stiffness = this@SpringConfig.stiffness |
| 765 | dampingRatio = this@SpringConfig.dampingRatio |
| 766 | finalPosition = this@SpringConfig.finalPosition |
| 767 | } |
| 768 | |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 769 | if (startVelocity != 0f) anim.setStartVelocity(startVelocity) |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 770 | } |
| 771 | } |
| 772 | |
| 773 | /** |
| 774 | * Container object for fling animation configuration settings. This allows you to store default |
| 775 | * friction values (as well as optional min/max values) in a single configuration object, which |
| 776 | * you can pass to [fling] and related methods. |
| 777 | */ |
| 778 | data class FlingConfig internal constructor( |
| 779 | internal var friction: Float, |
| 780 | internal var min: Float, |
| 781 | internal var max: Float, |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 782 | internal var startVelocity: Float |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 783 | ) { |
| 784 | |
| 785 | constructor() : this(defaultFling.friction) |
| 786 | |
| 787 | constructor(friction: Float) : |
| 788 | this(friction, defaultFling.min, defaultFling.max) |
| 789 | |
| 790 | constructor(friction: Float, min: Float, max: Float) : |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 791 | this(friction, min, max, startVelocity = 0f) |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 792 | |
| 793 | /** Apply these configuration settings to the given FlingAnimation. */ |
| 794 | internal fun applyToAnimation(anim: FlingAnimation) { |
| 795 | anim.apply { |
| 796 | friction = this@FlingConfig.friction |
| 797 | setMinValue(min) |
| 798 | setMaxValue(max) |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 799 | setStartVelocity(startVelocity) |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 800 | } |
| 801 | } |
| 802 | } |
| 803 | |
| 804 | /** |
| 805 | * Listener for receiving values from in progress animations. Used with |
| 806 | * [PhysicsAnimator.addUpdateListener]. |
| 807 | * |
| 808 | * @param <T> The type of the object being animated. |
| 809 | </T> */ |
| 810 | interface UpdateListener<T> { |
| 811 | |
| 812 | /** |
| 813 | * Called on each animation frame with the target object, and a map of FloatPropertyCompat |
| 814 | * -> AnimationUpdate, containing the latest value and velocity for that property. When |
| 815 | * multiple properties are animating together, the map will typically contain one entry for |
| 816 | * each property. However, you should never assume that this is the case - when a property |
| 817 | * animation ends earlier than the others, you'll receive an UpdateMap containing only that |
| 818 | * property's final update. Subsequently, you'll only receive updates for the properties |
| 819 | * that are still animating. |
| 820 | * |
| 821 | * Always check that the map contains an update for the property you're interested in before |
| 822 | * accessing it. |
| 823 | * |
| 824 | * @param target The animated object itself. |
| 825 | * @param values Map of property to AnimationUpdate, which contains that property |
| 826 | * animation's latest value and velocity. You should never assume that a particular property |
| 827 | * is present in this map. |
| 828 | */ |
| 829 | fun onAnimationUpdateForProperty( |
| 830 | target: T, |
| 831 | values: UpdateMap<T> |
| 832 | ) |
| 833 | } |
| 834 | |
| 835 | /** |
| 836 | * Listener for receiving callbacks when animations end. |
| 837 | * |
| 838 | * @param <T> The type of the object being animated. |
| 839 | </T> */ |
| 840 | interface EndListener<T> { |
| 841 | |
| 842 | /** |
| 843 | * Called with the final animation values as each property animation ends. This can be used |
| 844 | * to respond to specific property animations concluding (such as hiding a view when ALPHA |
| 845 | * ends, even if the corresponding TRANSLATION animations have not ended). |
| 846 | * |
| 847 | * If you just want to run an action when all of the property animations have ended, you can |
| 848 | * use [PhysicsAnimator.withEndActions]. |
| 849 | * |
| 850 | * @param target The animated object itself. |
| 851 | * @param property The property whose animation has just ended. |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 852 | * @param wasFling Whether this property ended after a fling animation (as opposed to a |
| 853 | * spring animation). If this property was animated via [flingThenSpring], this will be true |
| 854 | * if the fling animation did not reach the min/max bounds, decelerating to a stop |
| 855 | * naturally. It will be false if it hit the bounds and was sprung back. |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 856 | * @param canceled Whether the animation was explicitly canceled before it naturally ended. |
| 857 | * @param finalValue The final value of the animated property. |
| 858 | * @param finalVelocity The final velocity (in pixels per second) of the ended animation. |
| 859 | * This is typically zero, unless this was a fling animation which ended abruptly due to |
| 860 | * reaching its configured min/max values. |
| 861 | * @param allRelevantPropertyAnimsEnded Whether all properties relevant to this end listener |
| 862 | * have ended. Relevant properties are those which were animated alongside the |
| 863 | * [addEndListener] call where this animator was passed in. For example: |
| 864 | * |
| 865 | * animator |
| 866 | * .spring(TRANSLATION_X, 100f) |
| 867 | * .spring(TRANSLATION_Y, 200f) |
| 868 | * .withEndListener(firstEndListener) |
| 869 | * .start() |
| 870 | * |
| 871 | * firstEndListener will be called first for TRANSLATION_X, with allEnded = false, |
| 872 | * because TRANSLATION_Y is still running. When TRANSLATION_Y ends, it'll be called with |
| 873 | * allEnded = true. |
| 874 | * |
| 875 | * If a subsequent call to start() is made with other properties, those properties are not |
| 876 | * considered relevant and allEnded will still equal true when only TRANSLATION_X and |
| 877 | * TRANSLATION_Y end. For example, if immediately after the prior example, while |
| 878 | * TRANSLATION_X and TRANSLATION_Y are still animating, we called: |
| 879 | * |
| 880 | * animator. |
| 881 | * .spring(SCALE_X, 2f, stiffness = 10f) // That will take awhile... |
| 882 | * .withEndListener(secondEndListener) |
| 883 | * .start() |
| 884 | * |
| 885 | * firstEndListener will still be called with allEnded = true when TRANSLATION_X/Y end, even |
| 886 | * though SCALE_X is still animating. Similarly, secondEndListener will be called with |
| 887 | * allEnded = true as soon as SCALE_X ends, even if the translation animations are still |
| 888 | * running. |
| 889 | */ |
| 890 | fun onAnimationEnd( |
| 891 | target: T, |
| 892 | property: FloatPropertyCompat<in T>, |
Joshua Tsuji | aaace7f | 2019-12-16 17:03:08 -0500 | [diff] [blame] | 893 | wasFling: Boolean, |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 894 | canceled: Boolean, |
| 895 | finalValue: Float, |
| 896 | finalVelocity: Float, |
| 897 | allRelevantPropertyAnimsEnded: Boolean |
| 898 | ) |
| 899 | } |
| 900 | |
| 901 | companion object { |
| 902 | |
| 903 | /** |
| 904 | * Constructor to use to for new physics animator instances in [getInstance]. This is |
| 905 | * typically the default constructor, but [PhysicsAnimatorTestUtils] can change it so that |
| 906 | * all code using the physics animator is given testable instances instead. |
| 907 | */ |
| 908 | internal var instanceConstructor: (Any) -> PhysicsAnimator<*> = ::PhysicsAnimator |
| 909 | |
| 910 | @JvmStatic |
Joshua Tsuji | 569b5dc | 2019-12-19 14:14:58 -0500 | [diff] [blame] | 911 | @Suppress("UNCHECKED_CAST") |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 912 | fun <T : Any> getInstance(target: T): PhysicsAnimator<T> { |
| 913 | if (!animators.containsKey(target)) { |
| 914 | animators[target] = instanceConstructor(target) |
| 915 | } |
| 916 | |
| 917 | return animators[target] as PhysicsAnimator<T> |
| 918 | } |
| 919 | |
| 920 | /** |
| 921 | * Set whether all physics animators should log a lot of information about animations. |
| 922 | * Useful for debugging! |
| 923 | */ |
| 924 | @JvmStatic |
| 925 | fun setVerboseLogging(debug: Boolean) { |
| 926 | verboseLogging = debug |
| 927 | } |
| 928 | |
Joshua Tsuji | 5b139c3 | 2020-01-30 18:03:09 -0500 | [diff] [blame] | 929 | /** |
| 930 | * Estimates the end value of a fling that starts at the given value using the provided |
| 931 | * start velocity and fling configuration. |
| 932 | * |
| 933 | * This is only an estimate. Fling animations use a timing-based physics simulation that is |
| 934 | * non-deterministic, so this exact value may not be reached. |
| 935 | */ |
| 936 | @JvmStatic |
| 937 | fun estimateFlingEndValue( |
| 938 | startValue: Float, |
| 939 | startVelocity: Float, |
| 940 | flingConfig: FlingConfig |
| 941 | ): Float { |
| 942 | val distance = startVelocity / (flingConfig.friction * FLING_FRICTION_SCALAR_MULTIPLIER) |
| 943 | return Math.min(flingConfig.max, Math.max(flingConfig.min, startValue + distance)) |
| 944 | } |
| 945 | |
Joshua Tsuji | 408b959 | 2019-11-07 18:32:58 -0500 | [diff] [blame] | 946 | @JvmStatic |
| 947 | fun getReadablePropertyName(property: FloatPropertyCompat<*>): String { |
| 948 | return when (property) { |
| 949 | DynamicAnimation.TRANSLATION_X -> "translationX" |
| 950 | DynamicAnimation.TRANSLATION_Y -> "translationY" |
| 951 | DynamicAnimation.TRANSLATION_Z -> "translationZ" |
| 952 | DynamicAnimation.SCALE_X -> "scaleX" |
| 953 | DynamicAnimation.SCALE_Y -> "scaleY" |
| 954 | DynamicAnimation.ROTATION -> "rotation" |
| 955 | DynamicAnimation.ROTATION_X -> "rotationX" |
| 956 | DynamicAnimation.ROTATION_Y -> "rotationY" |
| 957 | DynamicAnimation.SCROLL_X -> "scrollX" |
| 958 | DynamicAnimation.SCROLL_Y -> "scrollY" |
| 959 | DynamicAnimation.ALPHA -> "alpha" |
| 960 | else -> "Custom FloatPropertyCompat instance" |
| 961 | } |
| 962 | } |
| 963 | } |
| 964 | } |