Ben Lin | 743fe59 | 2017-03-01 14:36:15 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2017 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.documentsui.dirlist; |
| 18 | |
| 19 | import android.animation.Animator; |
| 20 | import android.animation.AnimatorListenerAdapter; |
| 21 | import android.animation.ValueAnimator; |
| 22 | import android.animation.ValueAnimator.AnimatorUpdateListener; |
| 23 | import android.graphics.Canvas; |
| 24 | import android.graphics.drawable.Drawable; |
| 25 | import android.graphics.drawable.StateListDrawable; |
| 26 | import android.support.annotation.IntDef; |
| 27 | import android.support.annotation.Nullable; |
| 28 | import android.support.annotation.VisibleForTesting; |
| 29 | import android.support.v4.view.ViewCompat; |
| 30 | import android.support.v7.widget.RecyclerView; |
| 31 | import android.support.v7.widget.RecyclerView.ItemDecoration; |
| 32 | import android.support.v7.widget.RecyclerView.OnItemTouchListener; |
| 33 | import android.support.v7.widget.RecyclerView.OnScrollListener; |
| 34 | import android.view.MotionEvent; |
| 35 | |
| 36 | /** |
| 37 | * Class responsible to animate and provide a fast scroller. |
| 38 | * |
| 39 | * Replace with supportlib version once released. See b/30713593. |
| 40 | */ |
| 41 | @VisibleForTesting |
| 42 | class FastScroller extends ItemDecoration implements OnItemTouchListener { |
| 43 | @IntDef({STATE_HIDDEN, STATE_VISIBLE, STATE_DRAGGING}) |
| 44 | private @interface State { } |
| 45 | // Scroll thumb not showing |
| 46 | private static final int STATE_HIDDEN = 0; |
| 47 | // Scroll thumb visible and moving along with the scrollbar |
| 48 | private static final int STATE_VISIBLE = 1; |
| 49 | // Scroll thumb being dragged by user |
| 50 | private static final int STATE_DRAGGING = 2; |
| 51 | |
| 52 | @IntDef({DRAG_X, DRAG_Y, DRAG_NONE}) |
| 53 | private @interface DragState{ } |
| 54 | private static final int DRAG_NONE = 0; |
| 55 | private static final int DRAG_X = 1; |
| 56 | private static final int DRAG_Y = 2; |
| 57 | |
| 58 | @IntDef({ANIMATION_STATE_OUT, ANIMATION_STATE_FADING_IN, ANIMATION_STATE_IN, |
| 59 | ANIMATION_STATE_FADING_OUT}) |
| 60 | private @interface AnimationState { } |
| 61 | private static final int ANIMATION_STATE_OUT = 0; |
| 62 | private static final int ANIMATION_STATE_FADING_IN = 1; |
| 63 | private static final int ANIMATION_STATE_IN = 2; |
| 64 | private static final int ANIMATION_STATE_FADING_OUT = 3; |
| 65 | |
| 66 | private static final int SHOW_DURATION_MS = 500; |
| 67 | private static final int HIDE_DELAY_AFTER_VISIBLE_MS = 1500; |
| 68 | private static final int HIDE_DELAY_AFTER_DRAGGING_MS = 1200; |
| 69 | private static final int HIDE_DURATION_MS = 500; |
| 70 | private static final int SCROLLBAR_FULL_OPAQUE = 255; |
| 71 | |
| 72 | private static final int[] PRESSED_STATE_SET = new int[]{android.R.attr.state_pressed}; |
| 73 | private static final int[] EMPTY_STATE_SET = new int[]{}; |
| 74 | |
| 75 | private final int mScrollbarMinimumRange; |
| 76 | private final int mMargin; |
| 77 | |
| 78 | // Final values for the vertical scroll bar |
| 79 | private final StateListDrawable mVerticalThumbDrawable; |
| 80 | private final Drawable mVerticalTrackDrawable; |
| 81 | private final int mVerticalThumbWidth; |
| 82 | private final int mVerticalTrackWidth; |
| 83 | |
| 84 | // Final values for the horizontal scroll bar |
| 85 | private final StateListDrawable mHorizontalThumbDrawable; |
| 86 | private final Drawable mHorizontalTrackDrawable; |
| 87 | private final int mHorizontalThumbHeight; |
| 88 | private final int mHorizontalTrackHeight; |
| 89 | |
| 90 | // Dynamic values for the vertical scroll bar |
| 91 | @VisibleForTesting int mVerticalThumbHeight; |
| 92 | @VisibleForTesting int mVerticalThumbCenterY; |
| 93 | @VisibleForTesting float mVerticalDragY; |
| 94 | |
| 95 | // Dynamic values for the horizontal scroll bar |
| 96 | @VisibleForTesting int mHorizontalThumbWidth; |
| 97 | @VisibleForTesting int mHorizontalThumbCenterX; |
| 98 | @VisibleForTesting float mHorizontalDragX; |
| 99 | |
| 100 | private int mRecyclerViewWidth = 0; |
| 101 | private int mRecyclerViewHeight = 0; |
| 102 | |
| 103 | private RecyclerView mRecyclerView; |
| 104 | /** |
| 105 | * Whether the document is long/wide enough to require scrolling. If not, we don't show the |
| 106 | * relevant scroller. |
| 107 | */ |
| 108 | private boolean mNeedVerticalScrollbar = false; |
| 109 | private boolean mNeedHorizontalScrollbar = false; |
| 110 | @State private int mState = STATE_HIDDEN; |
| 111 | @DragState private int mDragState = DRAG_NONE; |
| 112 | |
| 113 | private final int[] mVerticalRange = new int[2]; |
| 114 | private final int[] mHorizontalRange = new int[2]; |
| 115 | private final ValueAnimator mShowHideAnimator = ValueAnimator.ofFloat(0, 1); |
| 116 | @AnimationState private int mAnimationState = ANIMATION_STATE_OUT; |
| 117 | private final Runnable mHideRunnable = new Runnable() { |
| 118 | @Override |
| 119 | public void run() { |
| 120 | hide(HIDE_DURATION_MS); |
| 121 | } |
| 122 | }; |
| 123 | private final OnScrollListener mOnScrollListener = new OnScrollListener() { |
| 124 | @Override |
| 125 | public void onScrolled(RecyclerView recyclerView, int dx, int dy) { |
| 126 | updateScrollPosition(recyclerView.computeHorizontalScrollOffset(), |
| 127 | recyclerView.computeVerticalScrollOffset()); |
| 128 | } |
| 129 | }; |
| 130 | |
| 131 | FastScroller(RecyclerView recyclerView, StateListDrawable verticalThumbDrawable, |
| 132 | Drawable verticalTrackDrawable, StateListDrawable horizontalThumbDrawable, |
| 133 | Drawable horizontalTrackDrawable, int defaultWidth, int scrollbarMinimumRange, |
| 134 | int margin) { |
| 135 | mVerticalThumbDrawable = verticalThumbDrawable; |
| 136 | mVerticalTrackDrawable = verticalTrackDrawable; |
| 137 | mHorizontalThumbDrawable = horizontalThumbDrawable; |
| 138 | mHorizontalTrackDrawable = horizontalTrackDrawable; |
| 139 | mVerticalThumbWidth = Math.max(defaultWidth, verticalThumbDrawable.getIntrinsicWidth()); |
| 140 | mVerticalTrackWidth = Math.max(defaultWidth, verticalTrackDrawable.getIntrinsicWidth()); |
| 141 | mHorizontalThumbHeight = Math |
| 142 | .max(defaultWidth, horizontalThumbDrawable.getIntrinsicWidth()); |
| 143 | mHorizontalTrackHeight = Math |
| 144 | .max(defaultWidth, horizontalTrackDrawable.getIntrinsicWidth()); |
| 145 | mScrollbarMinimumRange = scrollbarMinimumRange; |
| 146 | mMargin = margin; |
| 147 | mVerticalThumbDrawable.setAlpha(SCROLLBAR_FULL_OPAQUE); |
| 148 | mVerticalTrackDrawable.setAlpha(SCROLLBAR_FULL_OPAQUE); |
| 149 | |
| 150 | mShowHideAnimator.addListener(new AnimatorListener()); |
| 151 | mShowHideAnimator.addUpdateListener(new AnimatorUpdater()); |
| 152 | |
| 153 | attachToRecyclerView(recyclerView); |
| 154 | } |
| 155 | |
| 156 | public void attachToRecyclerView(@Nullable RecyclerView recyclerView) { |
| 157 | if (mRecyclerView == recyclerView) { |
| 158 | return; // nothing to do |
| 159 | } |
| 160 | if (mRecyclerView != null) { |
| 161 | destroyCallbacks(); |
| 162 | } |
| 163 | mRecyclerView = recyclerView; |
| 164 | if (mRecyclerView != null) { |
| 165 | setupCallbacks(); |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | private void setupCallbacks() { |
| 170 | mRecyclerView.addItemDecoration(this); |
| 171 | mRecyclerView.addOnItemTouchListener(this); |
| 172 | mRecyclerView.addOnScrollListener(mOnScrollListener); |
| 173 | } |
| 174 | |
| 175 | private void destroyCallbacks() { |
| 176 | mRecyclerView.removeItemDecoration(this); |
| 177 | mRecyclerView.removeOnItemTouchListener(this); |
| 178 | mRecyclerView.removeOnScrollListener(mOnScrollListener); |
| 179 | cancelHide(); |
| 180 | } |
| 181 | |
| 182 | private void requestRedraw() { |
| 183 | mRecyclerView.invalidate(); |
| 184 | } |
| 185 | |
| 186 | private void setState(@State int state) { |
| 187 | if (state == STATE_DRAGGING && mState != STATE_DRAGGING) { |
| 188 | mVerticalThumbDrawable.setState(PRESSED_STATE_SET); |
| 189 | cancelHide(); |
| 190 | } |
| 191 | |
| 192 | if (state == STATE_HIDDEN) { |
| 193 | requestRedraw(); |
| 194 | } else { |
| 195 | show(); |
| 196 | } |
| 197 | |
| 198 | if (mState == STATE_DRAGGING && state != STATE_DRAGGING) { |
| 199 | mVerticalThumbDrawable.setState(EMPTY_STATE_SET); |
| 200 | resetHideDelay(HIDE_DELAY_AFTER_DRAGGING_MS); |
| 201 | } else if (state == STATE_VISIBLE) { |
| 202 | resetHideDelay(HIDE_DELAY_AFTER_VISIBLE_MS); |
| 203 | } |
| 204 | mState = state; |
| 205 | } |
| 206 | |
| 207 | private boolean isLayoutRTL() { |
| 208 | return ViewCompat.getLayoutDirection(mRecyclerView) == ViewCompat.LAYOUT_DIRECTION_RTL; |
| 209 | } |
| 210 | |
| 211 | public boolean isDragging() { |
| 212 | return mState == STATE_DRAGGING; |
| 213 | } |
| 214 | |
| 215 | @VisibleForTesting boolean isVisible() { |
| 216 | return mState == STATE_VISIBLE; |
| 217 | } |
| 218 | |
| 219 | @VisibleForTesting boolean isHidden() { |
| 220 | return mState == STATE_HIDDEN; |
| 221 | } |
| 222 | |
| 223 | |
| 224 | public void show() { |
| 225 | switch (mAnimationState) { |
| 226 | case ANIMATION_STATE_FADING_OUT: |
| 227 | mShowHideAnimator.cancel(); |
| 228 | // no break |
| 229 | case ANIMATION_STATE_OUT: |
| 230 | mAnimationState = ANIMATION_STATE_FADING_IN; |
| 231 | mShowHideAnimator.setFloatValues((float) mShowHideAnimator.getAnimatedValue(), 1); |
| 232 | mShowHideAnimator.setDuration(SHOW_DURATION_MS); |
| 233 | mShowHideAnimator.setStartDelay(0); |
| 234 | mShowHideAnimator.start(); |
| 235 | break; |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | public void hide() { |
| 240 | hide(0); |
| 241 | } |
| 242 | |
| 243 | @VisibleForTesting |
| 244 | void hide(int duration) { |
| 245 | switch (mAnimationState) { |
| 246 | case ANIMATION_STATE_FADING_IN: |
| 247 | mShowHideAnimator.cancel(); |
| 248 | // no break |
| 249 | case ANIMATION_STATE_IN: |
| 250 | mAnimationState = ANIMATION_STATE_FADING_OUT; |
| 251 | mShowHideAnimator.setFloatValues((float) mShowHideAnimator.getAnimatedValue(), 0); |
| 252 | mShowHideAnimator.setDuration(duration); |
| 253 | mShowHideAnimator.start(); |
| 254 | break; |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | private void cancelHide() { |
| 259 | mRecyclerView.removeCallbacks(mHideRunnable); |
| 260 | } |
| 261 | |
| 262 | private void resetHideDelay(int delay) { |
| 263 | cancelHide(); |
| 264 | mRecyclerView.postDelayed(mHideRunnable, delay); |
| 265 | } |
| 266 | |
| 267 | @Override |
| 268 | public void onDrawOver(Canvas canvas, RecyclerView parent, RecyclerView.State state) { |
| 269 | if (mRecyclerViewWidth != mRecyclerView.getWidth() |
| 270 | || mRecyclerViewHeight != mRecyclerView.getHeight()) { |
| 271 | mRecyclerViewWidth = mRecyclerView.getWidth(); |
| 272 | mRecyclerViewHeight = mRecyclerView.getHeight(); |
| 273 | // This is due to the different events ordering when keyboard is opened or |
| 274 | // retracted vs rotate. Hence to avoid corner cases we just disable the |
| 275 | // scroller when size changed, and wait until the scroll position is recomputed |
| 276 | // before showing it back. |
| 277 | setState(STATE_HIDDEN); |
| 278 | return; |
| 279 | } |
| 280 | |
| 281 | if (mAnimationState != ANIMATION_STATE_OUT) { |
| 282 | if (mNeedVerticalScrollbar) { |
| 283 | drawVerticalScrollbar(canvas); |
| 284 | } |
| 285 | if (mNeedHorizontalScrollbar) { |
| 286 | drawHorizontalScrollbar(canvas); |
| 287 | } |
| 288 | } |
| 289 | } |
| 290 | |
| 291 | private void drawVerticalScrollbar(Canvas canvas) { |
| 292 | int viewWidth = mRecyclerViewWidth; |
| 293 | |
| 294 | int left = viewWidth - mVerticalThumbWidth; |
| 295 | int top = mVerticalThumbCenterY - mVerticalThumbHeight / 2; |
| 296 | mVerticalThumbDrawable.setBounds(0, 0, mVerticalThumbWidth, mVerticalThumbHeight); |
| 297 | mVerticalTrackDrawable |
| 298 | .setBounds(0, 0, mVerticalTrackWidth, mRecyclerViewHeight); |
| 299 | |
| 300 | if (isLayoutRTL()) { |
| 301 | mVerticalTrackDrawable.draw(canvas); |
| 302 | canvas.translate(mVerticalThumbWidth, top); |
| 303 | canvas.scale(-1, 1); |
| 304 | mVerticalThumbDrawable.draw(canvas); |
| 305 | canvas.scale(1, 1); |
| 306 | canvas.translate(-mVerticalThumbWidth, -top); |
| 307 | } else { |
| 308 | canvas.translate(left, 0); |
| 309 | mVerticalTrackDrawable.draw(canvas); |
| 310 | canvas.translate(0, top); |
| 311 | mVerticalThumbDrawable.draw(canvas); |
| 312 | canvas.translate(-left, -top); |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | private void drawHorizontalScrollbar(Canvas canvas) { |
| 317 | int viewHeight = mRecyclerViewHeight; |
| 318 | |
| 319 | int top = viewHeight - mHorizontalThumbHeight; |
| 320 | int left = mHorizontalThumbCenterX - mHorizontalThumbWidth / 2; |
| 321 | mHorizontalThumbDrawable.setBounds(0, 0, mHorizontalThumbWidth, mHorizontalThumbHeight); |
| 322 | mHorizontalTrackDrawable |
| 323 | .setBounds(0, 0, mRecyclerViewWidth, mHorizontalTrackHeight); |
| 324 | |
| 325 | canvas.translate(0, top); |
| 326 | mHorizontalTrackDrawable.draw(canvas); |
| 327 | canvas.translate(left, 0); |
| 328 | mHorizontalThumbDrawable.draw(canvas); |
| 329 | canvas.translate(-left, -top); |
| 330 | } |
| 331 | |
| 332 | /** |
| 333 | * Notify the scroller of external change of the scroll, e.g. through dragging or flinging on |
| 334 | * the view itself. |
| 335 | * |
| 336 | * @param offsetX The new scroll X offset. |
| 337 | * @param offsetY The new scroll Y offset. |
| 338 | */ |
| 339 | void updateScrollPosition(int offsetX, int offsetY) { |
| 340 | int verticalContentLength = mRecyclerView.computeVerticalScrollRange(); |
| 341 | int verticalVisibleLength = mRecyclerViewHeight; |
| 342 | mNeedVerticalScrollbar = verticalContentLength - verticalVisibleLength > 0 |
| 343 | && mRecyclerViewHeight >= mScrollbarMinimumRange; |
| 344 | |
| 345 | int horizontalContentLength = mRecyclerView.computeHorizontalScrollRange(); |
| 346 | int horizontalVisibleLength = mRecyclerViewWidth; |
| 347 | mNeedHorizontalScrollbar = horizontalContentLength - horizontalVisibleLength > 0 |
| 348 | && mRecyclerViewWidth >= mScrollbarMinimumRange; |
| 349 | |
| 350 | if (!mNeedVerticalScrollbar && !mNeedHorizontalScrollbar) { |
| 351 | if (mState != STATE_HIDDEN) { |
| 352 | setState(STATE_HIDDEN); |
| 353 | } |
| 354 | return; |
| 355 | } |
| 356 | |
| 357 | if (mNeedVerticalScrollbar) { |
| 358 | float middleScreenPos = offsetY + verticalVisibleLength / 2.0f; |
| 359 | mVerticalThumbCenterY = |
| 360 | (int) ((verticalVisibleLength * middleScreenPos) / verticalContentLength); |
| 361 | mVerticalThumbHeight = Math.min(verticalVisibleLength, |
| 362 | (verticalVisibleLength * verticalVisibleLength) / verticalContentLength); |
| 363 | } |
| 364 | |
| 365 | if (mNeedHorizontalScrollbar) { |
| 366 | float middleScreenPos = offsetX + horizontalVisibleLength / 2.0f; |
| 367 | mHorizontalThumbCenterX = |
| 368 | (int) ((horizontalVisibleLength * middleScreenPos) / horizontalContentLength); |
| 369 | mHorizontalThumbWidth = Math.min(horizontalVisibleLength, |
| 370 | (horizontalVisibleLength * horizontalVisibleLength) / horizontalContentLength); |
| 371 | } |
| 372 | |
| 373 | if (mState == STATE_HIDDEN || mState == STATE_VISIBLE) { |
| 374 | setState(STATE_VISIBLE); |
| 375 | } |
| 376 | } |
| 377 | |
| 378 | @Override |
| 379 | public boolean onInterceptTouchEvent(RecyclerView recyclerView, MotionEvent ev) { |
| 380 | final boolean handled; |
| 381 | if (mState == STATE_VISIBLE) { |
| 382 | boolean insideVerticalThumb = isPointInsideVerticalThumb(ev.getX(), ev.getY()); |
| 383 | boolean insideHorizontalThumb = isPointInsideHorizontalThumb(ev.getX(), ev.getY()); |
| 384 | if (ev.getAction() == MotionEvent.ACTION_DOWN |
| 385 | && (insideVerticalThumb || insideHorizontalThumb)) { |
| 386 | if (insideHorizontalThumb) { |
| 387 | mDragState = DRAG_X; |
| 388 | mHorizontalDragX = (int) ev.getX(); |
| 389 | } else if (insideVerticalThumb) { |
| 390 | mDragState = DRAG_Y; |
| 391 | mVerticalDragY = (int) ev.getY(); |
| 392 | } |
| 393 | |
| 394 | setState(STATE_DRAGGING); |
| 395 | handled = true; |
| 396 | } else { |
| 397 | handled = false; |
| 398 | } |
| 399 | } else if (mState == STATE_DRAGGING) { |
| 400 | handled = true; |
| 401 | } else { |
| 402 | handled = false; |
| 403 | } |
| 404 | return handled; |
| 405 | } |
| 406 | |
| 407 | @Override |
| 408 | public void onTouchEvent(RecyclerView recyclerView, MotionEvent me) { |
| 409 | if (mState == STATE_HIDDEN) { |
| 410 | return; |
| 411 | } |
| 412 | |
| 413 | if (me.getAction() == MotionEvent.ACTION_DOWN) { |
| 414 | boolean insideVerticalThumb = isPointInsideVerticalThumb(me.getX(), me.getY()); |
| 415 | boolean insideHorizontalThumb = isPointInsideHorizontalThumb(me.getX(), me.getY()); |
| 416 | if (insideVerticalThumb || insideHorizontalThumb) { |
| 417 | if (insideHorizontalThumb) { |
| 418 | mDragState = DRAG_X; |
| 419 | mHorizontalDragX = (int) me.getX(); |
| 420 | } else if (insideVerticalThumb) { |
| 421 | mDragState = DRAG_Y; |
| 422 | mVerticalDragY = (int) me.getY(); |
| 423 | } |
| 424 | setState(STATE_DRAGGING); |
| 425 | } |
| 426 | } else if (me.getAction() == MotionEvent.ACTION_UP && mState == STATE_DRAGGING) { |
| 427 | mVerticalDragY = 0; |
| 428 | mHorizontalDragX = 0; |
| 429 | setState(STATE_VISIBLE); |
| 430 | mDragState = DRAG_NONE; |
| 431 | } else if (me.getAction() == MotionEvent.ACTION_MOVE && mState == STATE_DRAGGING) { |
| 432 | show(); |
| 433 | if (mDragState == DRAG_X) { |
| 434 | horizontalScrollTo(me.getX()); |
| 435 | } |
| 436 | if (mDragState == DRAG_Y) { |
| 437 | verticalScrollTo(me.getY()); |
| 438 | } |
| 439 | } |
| 440 | } |
| 441 | |
| 442 | @Override |
| 443 | public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { } |
| 444 | |
| 445 | private void verticalScrollTo(float y) { |
| 446 | final int[] scrollbarRange = getVerticalRange(); |
| 447 | y = Math.max(scrollbarRange[0], Math.min(scrollbarRange[1], y)); |
| 448 | if (Math.abs(mVerticalThumbCenterY - y) < 2) { |
| 449 | return; |
| 450 | } |
| 451 | int scrollingBy = scrollTo(mVerticalDragY, y, scrollbarRange, |
| 452 | mRecyclerView.computeVerticalScrollRange(), |
| 453 | mRecyclerView.computeVerticalScrollOffset(), mRecyclerViewHeight); |
| 454 | if (scrollingBy != 0) { |
| 455 | mRecyclerView.scrollBy(0, scrollingBy); |
| 456 | } |
| 457 | mVerticalDragY = y; |
| 458 | } |
| 459 | |
| 460 | private void horizontalScrollTo(float x) { |
| 461 | final int[] scrollbarRange = getHorizontalRange(); |
| 462 | x = Math.max(scrollbarRange[0], Math.min(scrollbarRange[1], x)); |
| 463 | if (Math.abs(mHorizontalThumbCenterX - x) < 2) { |
| 464 | return; |
| 465 | } |
| 466 | |
| 467 | int scrollingBy = scrollTo(mHorizontalDragX, x, scrollbarRange, |
| 468 | mRecyclerView.computeHorizontalScrollRange(), |
| 469 | mRecyclerView.computeHorizontalScrollOffset(), mRecyclerViewWidth); |
| 470 | if (scrollingBy != 0) { |
| 471 | mRecyclerView.scrollBy(scrollingBy, 0); |
| 472 | } |
| 473 | |
| 474 | mHorizontalDragX = x; |
| 475 | } |
| 476 | |
| 477 | private int scrollTo(float oldDragPos, float newDragPos, int[] scrollbarRange, int scrollRange, |
| 478 | int scrollOffset, int viewLength) { |
| 479 | int scrollbarLength = scrollbarRange[1] - scrollbarRange[0]; |
| 480 | if (scrollbarLength == 0) { |
| 481 | return 0; |
| 482 | } |
| 483 | float percentage = ((newDragPos - oldDragPos) / (float) scrollbarLength); |
| 484 | int totalPossibleOffset = scrollRange - viewLength; |
| 485 | int scrollingBy = (int) (percentage * totalPossibleOffset); |
| 486 | int absoluteOffset = scrollOffset + scrollingBy; |
| 487 | if (absoluteOffset < totalPossibleOffset && absoluteOffset >= 0) { |
| 488 | return scrollingBy; |
| 489 | } else { |
| 490 | return 0; |
| 491 | } |
| 492 | } |
| 493 | |
| 494 | @VisibleForTesting |
| 495 | boolean isPointInsideVerticalThumb(float x, float y) { |
| 496 | return (isLayoutRTL() ? x <= mVerticalThumbWidth / 2 |
| 497 | : x >= mRecyclerViewWidth - mVerticalThumbWidth) |
| 498 | && y >= mVerticalThumbCenterY - mVerticalThumbHeight / 2 |
| 499 | && y <= mVerticalThumbCenterY + mVerticalThumbHeight / 2; |
| 500 | } |
| 501 | |
| 502 | @VisibleForTesting |
| 503 | boolean isPointInsideHorizontalThumb(float x, float y) { |
| 504 | return (y >= mRecyclerViewHeight - mHorizontalThumbHeight) |
| 505 | && x >= mHorizontalThumbCenterX - mHorizontalThumbWidth / 2 |
| 506 | && x <= mHorizontalThumbCenterX + mHorizontalThumbWidth / 2; |
| 507 | } |
| 508 | |
| 509 | @VisibleForTesting |
| 510 | Drawable getHorizontalTrackDrawable() { |
| 511 | return mHorizontalTrackDrawable; |
| 512 | } |
| 513 | |
| 514 | @VisibleForTesting |
| 515 | Drawable getHorizontalThumbDrawable() { |
| 516 | return mHorizontalThumbDrawable; |
| 517 | } |
| 518 | |
| 519 | @VisibleForTesting |
| 520 | Drawable getVerticalTrackDrawable() { |
| 521 | return mVerticalTrackDrawable; |
| 522 | } |
| 523 | |
| 524 | @VisibleForTesting |
| 525 | Drawable getVerticalThumbDrawable() { |
| 526 | return mVerticalThumbDrawable; |
| 527 | } |
| 528 | |
| 529 | /** |
| 530 | * Gets the (min, max) vertical positions of the vertical scroll bar. |
| 531 | */ |
| 532 | private int[] getVerticalRange() { |
| 533 | mVerticalRange[0] = mMargin; |
| 534 | mVerticalRange[1] = mRecyclerViewHeight - mMargin; |
| 535 | return mVerticalRange; |
| 536 | } |
| 537 | |
| 538 | /** |
| 539 | * Gets the (min, max) horizontal positions of the horizontal scroll bar. |
| 540 | */ |
| 541 | private int[] getHorizontalRange() { |
| 542 | mHorizontalRange[0] = mMargin; |
| 543 | mHorizontalRange[1] = mRecyclerViewWidth - mMargin; |
| 544 | return mHorizontalRange; |
| 545 | } |
| 546 | |
| 547 | private class AnimatorListener extends AnimatorListenerAdapter { |
| 548 | |
| 549 | private boolean mCanceled = false; |
| 550 | |
| 551 | @Override |
| 552 | public void onAnimationEnd(Animator animation) { |
| 553 | // Cancel is always followed by a new directive, so don't update state. |
| 554 | if (mCanceled) { |
| 555 | mCanceled = false; |
| 556 | return; |
| 557 | } |
| 558 | if ((float) mShowHideAnimator.getAnimatedValue() == 0) { |
| 559 | mAnimationState = ANIMATION_STATE_OUT; |
| 560 | setState(STATE_HIDDEN); |
| 561 | } else { |
| 562 | mAnimationState = ANIMATION_STATE_IN; |
| 563 | requestRedraw(); |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | @Override |
| 568 | public void onAnimationCancel(Animator animation) { |
| 569 | mCanceled = true; |
| 570 | } |
| 571 | } |
| 572 | |
| 573 | private class AnimatorUpdater implements AnimatorUpdateListener { |
| 574 | |
| 575 | @Override |
| 576 | public void onAnimationUpdate(ValueAnimator valueAnimator) { |
| 577 | int alpha = (int) (SCROLLBAR_FULL_OPAQUE * ((float) valueAnimator.getAnimatedValue())); |
| 578 | mVerticalThumbDrawable.setAlpha(alpha); |
| 579 | mVerticalTrackDrawable.setAlpha(alpha); |
| 580 | requestRedraw(); |
| 581 | } |
| 582 | } |
| 583 | } |