The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package android.widget; |
| 18 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 19 | import android.annotation.Widget; |
| 20 | import android.content.Context; |
| 21 | import android.content.res.TypedArray; |
| 22 | import android.graphics.Rect; |
Svetoslav Ganov | 48d1586 | 2012-05-15 10:10:00 -0700 | [diff] [blame] | 23 | import android.os.Bundle; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 24 | import android.util.AttributeSet; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 25 | import android.util.Log; |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 26 | import android.view.ContextMenu.ContextMenuInfo; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 27 | import android.view.GestureDetector; |
| 28 | import android.view.Gravity; |
| 29 | import android.view.HapticFeedbackConstants; |
| 30 | import android.view.KeyEvent; |
| 31 | import android.view.MotionEvent; |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 32 | import android.view.SoundEffectConstants; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 33 | import android.view.View; |
| 34 | import android.view.ViewConfiguration; |
| 35 | import android.view.ViewGroup; |
Svetoslav Ganov | 8a78fd4 | 2012-01-17 14:36:46 -0800 | [diff] [blame] | 36 | import android.view.accessibility.AccessibilityEvent; |
| 37 | import android.view.accessibility.AccessibilityNodeInfo; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 38 | import android.view.animation.Transformation; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 39 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 40 | import com.android.internal.R; |
| 41 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 42 | /** |
| 43 | * A view that shows items in a center-locked, horizontally scrolling list. |
| 44 | * <p> |
| 45 | * The default values for the Gallery assume you will be using |
| 46 | * {@link android.R.styleable#Theme_galleryItemBackground} as the background for |
| 47 | * each View given to the Gallery from the Adapter. If you are not doing this, |
| 48 | * you may need to adjust some Gallery properties, such as the spacing. |
| 49 | * <p> |
| 50 | * Views given to the Gallery should use {@link Gallery.LayoutParams} as their |
| 51 | * layout parameters type. |
| 52 | * |
| 53 | * @attr ref android.R.styleable#Gallery_animationDuration |
| 54 | * @attr ref android.R.styleable#Gallery_spacing |
| 55 | * @attr ref android.R.styleable#Gallery_gravity |
Romain Guy | 5a418c7 | 2012-05-18 16:46:24 -0700 | [diff] [blame] | 56 | * |
Romain Guy | d2aed40 | 2012-05-18 17:32:08 -0700 | [diff] [blame] | 57 | * @deprecated This widget is no longer supported. Other horizontally scrolling |
| 58 | * widgets include {@link HorizontalScrollView} and {@link android.support.v4.view.ViewPager} |
| 59 | * from the support library. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 60 | */ |
Romain Guy | 5a418c7 | 2012-05-18 16:46:24 -0700 | [diff] [blame] | 61 | @Deprecated |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 62 | @Widget |
| 63 | public class Gallery extends AbsSpinner implements GestureDetector.OnGestureListener { |
| 64 | |
| 65 | private static final String TAG = "Gallery"; |
| 66 | |
Romain Guy | 8c11e31 | 2009-09-14 15:15:30 -0700 | [diff] [blame] | 67 | private static final boolean localLOGV = false; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 68 | |
| 69 | /** |
| 70 | * Duration in milliseconds from the start of a scroll during which we're |
| 71 | * unsure whether the user is scrolling or flinging. |
| 72 | */ |
| 73 | private static final int SCROLL_TO_FLING_UNCERTAINTY_TIMEOUT = 250; |
| 74 | |
| 75 | /** |
| 76 | * Horizontal spacing between items. |
| 77 | */ |
| 78 | private int mSpacing = 0; |
| 79 | |
| 80 | /** |
| 81 | * How long the transition animation should run when a child view changes |
| 82 | * position, measured in milliseconds. |
| 83 | */ |
| 84 | private int mAnimationDuration = 400; |
| 85 | |
| 86 | /** |
| 87 | * The alpha of items that are not selected. |
| 88 | */ |
| 89 | private float mUnselectedAlpha; |
| 90 | |
| 91 | /** |
| 92 | * Left most edge of a child seen so far during layout. |
| 93 | */ |
| 94 | private int mLeftMost; |
| 95 | |
| 96 | /** |
| 97 | * Right most edge of a child seen so far during layout. |
| 98 | */ |
| 99 | private int mRightMost; |
| 100 | |
| 101 | private int mGravity; |
| 102 | |
| 103 | /** |
| 104 | * Helper for detecting touch gestures. |
| 105 | */ |
| 106 | private GestureDetector mGestureDetector; |
| 107 | |
| 108 | /** |
| 109 | * The position of the item that received the user's down touch. |
| 110 | */ |
| 111 | private int mDownTouchPosition; |
| 112 | |
| 113 | /** |
| 114 | * The view of the item that received the user's down touch. |
| 115 | */ |
| 116 | private View mDownTouchView; |
| 117 | |
| 118 | /** |
| 119 | * Executes the delta scrolls from a fling or scroll movement. |
| 120 | */ |
| 121 | private FlingRunnable mFlingRunnable = new FlingRunnable(); |
| 122 | |
| 123 | /** |
| 124 | * Sets mSuppressSelectionChanged = false. This is used to set it to false |
| 125 | * in the future. It will also trigger a selection changed. |
| 126 | */ |
| 127 | private Runnable mDisableSuppressSelectionChangedRunnable = new Runnable() { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 128 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 129 | public void run() { |
| 130 | mSuppressSelectionChanged = false; |
| 131 | selectionChanged(); |
| 132 | } |
| 133 | }; |
| 134 | |
| 135 | /** |
| 136 | * When fling runnable runs, it resets this to false. Any method along the |
| 137 | * path until the end of its run() can set this to true to abort any |
| 138 | * remaining fling. For example, if we've reached either the leftmost or |
| 139 | * rightmost item, we will set this to true. |
| 140 | */ |
| 141 | private boolean mShouldStopFling; |
| 142 | |
| 143 | /** |
| 144 | * The currently selected item's child. |
| 145 | */ |
| 146 | private View mSelectedChild; |
| 147 | |
| 148 | /** |
| 149 | * Whether to continuously callback on the item selected listener during a |
| 150 | * fling. |
| 151 | */ |
| 152 | private boolean mShouldCallbackDuringFling = true; |
| 153 | |
| 154 | /** |
| 155 | * Whether to callback when an item that is not selected is clicked. |
| 156 | */ |
| 157 | private boolean mShouldCallbackOnUnselectedItemClick = true; |
| 158 | |
| 159 | /** |
| 160 | * If true, do not callback to item selected listener. |
| 161 | */ |
| 162 | private boolean mSuppressSelectionChanged; |
| 163 | |
| 164 | /** |
| 165 | * If true, we have received the "invoke" (center or enter buttons) key |
| 166 | * down. This is checked before we action on the "invoke" key up, and is |
| 167 | * subsequently cleared. |
| 168 | */ |
| 169 | private boolean mReceivedInvokeKeyDown; |
| 170 | |
| 171 | private AdapterContextMenuInfo mContextMenuInfo; |
| 172 | |
| 173 | /** |
| 174 | * If true, this onScroll is the first for this user's drag (remember, a |
| 175 | * drag sends many onScrolls). |
| 176 | */ |
| 177 | private boolean mIsFirstScroll; |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 178 | |
| 179 | /** |
| 180 | * If true, mFirstPosition is the position of the rightmost child, and |
| 181 | * the children are ordered right to left. |
| 182 | */ |
| 183 | private boolean mIsRtl = true; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 184 | |
Adam Powell | 4e8510b | 2012-09-28 14:04:48 -0700 | [diff] [blame] | 185 | /** |
| 186 | * Offset between the center of the selected child view and the center of the Gallery. |
| 187 | * Used to reset position correctly during layout. |
| 188 | */ |
| 189 | private int mSelectedCenterOffset; |
| 190 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 191 | public Gallery(Context context) { |
| 192 | this(context, null); |
| 193 | } |
| 194 | |
| 195 | public Gallery(Context context, AttributeSet attrs) { |
| 196 | this(context, attrs, R.attr.galleryStyle); |
| 197 | } |
| 198 | |
| 199 | public Gallery(Context context, AttributeSet attrs, int defStyle) { |
| 200 | super(context, attrs, defStyle); |
| 201 | |
| 202 | mGestureDetector = new GestureDetector(context, this); |
| 203 | mGestureDetector.setIsLongpressEnabled(true); |
| 204 | |
| 205 | TypedArray a = context.obtainStyledAttributes( |
| 206 | attrs, com.android.internal.R.styleable.Gallery, defStyle, 0); |
| 207 | |
| 208 | int index = a.getInt(com.android.internal.R.styleable.Gallery_gravity, -1); |
| 209 | if (index >= 0) { |
| 210 | setGravity(index); |
| 211 | } |
| 212 | |
| 213 | int animationDuration = |
| 214 | a.getInt(com.android.internal.R.styleable.Gallery_animationDuration, -1); |
| 215 | if (animationDuration > 0) { |
| 216 | setAnimationDuration(animationDuration); |
| 217 | } |
| 218 | |
| 219 | int spacing = |
| 220 | a.getDimensionPixelOffset(com.android.internal.R.styleable.Gallery_spacing, 0); |
| 221 | setSpacing(spacing); |
| 222 | |
| 223 | float unselectedAlpha = a.getFloat( |
| 224 | com.android.internal.R.styleable.Gallery_unselectedAlpha, 0.5f); |
| 225 | setUnselectedAlpha(unselectedAlpha); |
| 226 | |
| 227 | a.recycle(); |
| 228 | |
| 229 | // We draw the selected item last (because otherwise the item to the |
| 230 | // right overlaps it) |
| 231 | mGroupFlags |= FLAG_USE_CHILD_DRAWING_ORDER; |
| 232 | |
| 233 | mGroupFlags |= FLAG_SUPPORT_STATIC_TRANSFORMATIONS; |
| 234 | } |
| 235 | |
| 236 | /** |
| 237 | * Whether or not to callback on any {@link #getOnItemSelectedListener()} |
| 238 | * while the items are being flinged. If false, only the final selected item |
| 239 | * will cause the callback. If true, all items between the first and the |
| 240 | * final will cause callbacks. |
| 241 | * |
| 242 | * @param shouldCallback Whether or not to callback on the listener while |
| 243 | * the items are being flinged. |
| 244 | */ |
| 245 | public void setCallbackDuringFling(boolean shouldCallback) { |
| 246 | mShouldCallbackDuringFling = shouldCallback; |
| 247 | } |
| 248 | |
| 249 | /** |
| 250 | * Whether or not to callback when an item that is not selected is clicked. |
| 251 | * If false, the item will become selected (and re-centered). If true, the |
| 252 | * {@link #getOnItemClickListener()} will get the callback. |
| 253 | * |
| 254 | * @param shouldCallback Whether or not to callback on the listener when a |
| 255 | * item that is not selected is clicked. |
| 256 | * @hide |
| 257 | */ |
| 258 | public void setCallbackOnUnselectedItemClick(boolean shouldCallback) { |
| 259 | mShouldCallbackOnUnselectedItemClick = shouldCallback; |
| 260 | } |
| 261 | |
| 262 | /** |
| 263 | * Sets how long the transition animation should run when a child view |
| 264 | * changes position. Only relevant if animation is turned on. |
| 265 | * |
| 266 | * @param animationDurationMillis The duration of the transition, in |
| 267 | * milliseconds. |
| 268 | * |
| 269 | * @attr ref android.R.styleable#Gallery_animationDuration |
| 270 | */ |
| 271 | public void setAnimationDuration(int animationDurationMillis) { |
| 272 | mAnimationDuration = animationDurationMillis; |
| 273 | } |
| 274 | |
| 275 | /** |
| 276 | * Sets the spacing between items in a Gallery |
| 277 | * |
| 278 | * @param spacing The spacing in pixels between items in the Gallery |
| 279 | * |
| 280 | * @attr ref android.R.styleable#Gallery_spacing |
| 281 | */ |
| 282 | public void setSpacing(int spacing) { |
| 283 | mSpacing = spacing; |
| 284 | } |
| 285 | |
| 286 | /** |
| 287 | * Sets the alpha of items that are not selected in the Gallery. |
| 288 | * |
| 289 | * @param unselectedAlpha the alpha for the items that are not selected. |
| 290 | * |
| 291 | * @attr ref android.R.styleable#Gallery_unselectedAlpha |
| 292 | */ |
| 293 | public void setUnselectedAlpha(float unselectedAlpha) { |
| 294 | mUnselectedAlpha = unselectedAlpha; |
| 295 | } |
| 296 | |
| 297 | @Override |
| 298 | protected boolean getChildStaticTransformation(View child, Transformation t) { |
| 299 | |
| 300 | t.clear(); |
| 301 | t.setAlpha(child == mSelectedChild ? 1.0f : mUnselectedAlpha); |
| 302 | |
| 303 | return true; |
| 304 | } |
| 305 | |
| 306 | @Override |
| 307 | protected int computeHorizontalScrollExtent() { |
| 308 | // Only 1 item is considered to be selected |
| 309 | return 1; |
| 310 | } |
| 311 | |
| 312 | @Override |
| 313 | protected int computeHorizontalScrollOffset() { |
| 314 | // Current scroll position is the same as the selected position |
| 315 | return mSelectedPosition; |
| 316 | } |
| 317 | |
| 318 | @Override |
| 319 | protected int computeHorizontalScrollRange() { |
| 320 | // Scroll range is the same as the item count |
| 321 | return mItemCount; |
| 322 | } |
| 323 | |
| 324 | @Override |
| 325 | protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { |
| 326 | return p instanceof LayoutParams; |
| 327 | } |
| 328 | |
| 329 | @Override |
| 330 | protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { |
| 331 | return new LayoutParams(p); |
| 332 | } |
| 333 | |
| 334 | @Override |
| 335 | public ViewGroup.LayoutParams generateLayoutParams(AttributeSet attrs) { |
| 336 | return new LayoutParams(getContext(), attrs); |
| 337 | } |
| 338 | |
| 339 | @Override |
| 340 | protected ViewGroup.LayoutParams generateDefaultLayoutParams() { |
| 341 | /* |
| 342 | * Gallery expects Gallery.LayoutParams. |
| 343 | */ |
| 344 | return new Gallery.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, |
| 345 | ViewGroup.LayoutParams.WRAP_CONTENT); |
| 346 | } |
| 347 | |
| 348 | @Override |
| 349 | protected void onLayout(boolean changed, int l, int t, int r, int b) { |
| 350 | super.onLayout(changed, l, t, r, b); |
| 351 | |
| 352 | /* |
| 353 | * Remember that we are in layout to prevent more layout request from |
| 354 | * being generated. |
| 355 | */ |
| 356 | mInLayout = true; |
| 357 | layout(0, false); |
| 358 | mInLayout = false; |
| 359 | } |
| 360 | |
| 361 | @Override |
| 362 | int getChildHeight(View child) { |
| 363 | return child.getMeasuredHeight(); |
| 364 | } |
Svetoslav Ganov | a015617 | 2011-06-26 17:55:44 -0700 | [diff] [blame] | 365 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 366 | /** |
| 367 | * Tracks a motion scroll. In reality, this is used to do just about any |
| 368 | * movement to items (touch scroll, arrow-key scroll, set an item as selected). |
| 369 | * |
| 370 | * @param deltaX Change in X from the previous event. |
| 371 | */ |
| 372 | void trackMotionScroll(int deltaX) { |
| 373 | |
| 374 | if (getChildCount() == 0) { |
| 375 | return; |
| 376 | } |
| 377 | |
| 378 | boolean toLeft = deltaX < 0; |
| 379 | |
| 380 | int limitedDeltaX = getLimitedMotionScrollAmount(toLeft, deltaX); |
| 381 | if (limitedDeltaX != deltaX) { |
| 382 | // The above call returned a limited amount, so stop any scrolls/flings |
| 383 | mFlingRunnable.endFling(false); |
| 384 | onFinishedMovement(); |
| 385 | } |
| 386 | |
| 387 | offsetChildrenLeftAndRight(limitedDeltaX); |
| 388 | |
| 389 | detachOffScreenChildren(toLeft); |
| 390 | |
| 391 | if (toLeft) { |
| 392 | // If moved left, there will be empty space on the right |
| 393 | fillToGalleryRight(); |
| 394 | } else { |
| 395 | // Similarly, empty space on the left |
| 396 | fillToGalleryLeft(); |
| 397 | } |
| 398 | |
| 399 | // Clear unused views |
| 400 | mRecycler.clear(); |
| 401 | |
| 402 | setSelectionToCenterChild(); |
Svetoslav Ganov | a015617 | 2011-06-26 17:55:44 -0700 | [diff] [blame] | 403 | |
Adam Powell | 4e8510b | 2012-09-28 14:04:48 -0700 | [diff] [blame] | 404 | final View selChild = mSelectedChild; |
| 405 | if (selChild != null) { |
| 406 | final int childLeft = selChild.getLeft(); |
| 407 | final int childCenter = selChild.getWidth() / 2; |
| 408 | final int galleryCenter = getWidth() / 2; |
| 409 | mSelectedCenterOffset = childLeft + childCenter - galleryCenter; |
| 410 | } |
| 411 | |
Svetoslav Ganov | a015617 | 2011-06-26 17:55:44 -0700 | [diff] [blame] | 412 | onScrollChanged(0, 0, 0, 0); // dummy values, View's implementation does not use these. |
| 413 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 414 | invalidate(); |
| 415 | } |
| 416 | |
| 417 | int getLimitedMotionScrollAmount(boolean motionToLeft, int deltaX) { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 418 | int extremeItemPosition = motionToLeft != mIsRtl ? mItemCount - 1 : 0; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 419 | View extremeChild = getChildAt(extremeItemPosition - mFirstPosition); |
| 420 | |
| 421 | if (extremeChild == null) { |
| 422 | return deltaX; |
| 423 | } |
| 424 | |
| 425 | int extremeChildCenter = getCenterOfView(extremeChild); |
| 426 | int galleryCenter = getCenterOfGallery(); |
| 427 | |
| 428 | if (motionToLeft) { |
| 429 | if (extremeChildCenter <= galleryCenter) { |
| 430 | |
| 431 | // The extreme child is past his boundary point! |
| 432 | return 0; |
| 433 | } |
| 434 | } else { |
| 435 | if (extremeChildCenter >= galleryCenter) { |
| 436 | |
| 437 | // The extreme child is past his boundary point! |
| 438 | return 0; |
| 439 | } |
| 440 | } |
| 441 | |
| 442 | int centerDifference = galleryCenter - extremeChildCenter; |
| 443 | |
| 444 | return motionToLeft |
| 445 | ? Math.max(centerDifference, deltaX) |
| 446 | : Math.min(centerDifference, deltaX); |
| 447 | } |
| 448 | |
| 449 | /** |
| 450 | * Offset the horizontal location of all children of this view by the |
| 451 | * specified number of pixels. |
| 452 | * |
| 453 | * @param offset the number of pixels to offset |
| 454 | */ |
| 455 | private void offsetChildrenLeftAndRight(int offset) { |
| 456 | for (int i = getChildCount() - 1; i >= 0; i--) { |
| 457 | getChildAt(i).offsetLeftAndRight(offset); |
| 458 | } |
| 459 | } |
| 460 | |
| 461 | /** |
| 462 | * @return The center of this Gallery. |
| 463 | */ |
| 464 | private int getCenterOfGallery() { |
| 465 | return (getWidth() - mPaddingLeft - mPaddingRight) / 2 + mPaddingLeft; |
| 466 | } |
| 467 | |
| 468 | /** |
| 469 | * @return The center of the given view. |
| 470 | */ |
| 471 | private static int getCenterOfView(View view) { |
| 472 | return view.getLeft() + view.getWidth() / 2; |
| 473 | } |
| 474 | |
| 475 | /** |
| 476 | * Detaches children that are off the screen (i.e.: Gallery bounds). |
| 477 | * |
| 478 | * @param toLeft Whether to detach children to the left of the Gallery, or |
| 479 | * to the right. |
| 480 | */ |
| 481 | private void detachOffScreenChildren(boolean toLeft) { |
| 482 | int numChildren = getChildCount(); |
| 483 | int firstPosition = mFirstPosition; |
| 484 | int start = 0; |
| 485 | int count = 0; |
| 486 | |
| 487 | if (toLeft) { |
| 488 | final int galleryLeft = mPaddingLeft; |
| 489 | for (int i = 0; i < numChildren; i++) { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 490 | int n = mIsRtl ? (numChildren - 1 - i) : i; |
| 491 | final View child = getChildAt(n); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 492 | if (child.getRight() >= galleryLeft) { |
| 493 | break; |
| 494 | } else { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 495 | start = n; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 496 | count++; |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 497 | mRecycler.put(firstPosition + n, child); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 498 | } |
| 499 | } |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 500 | if (!mIsRtl) { |
| 501 | start = 0; |
| 502 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 503 | } else { |
| 504 | final int galleryRight = getWidth() - mPaddingRight; |
| 505 | for (int i = numChildren - 1; i >= 0; i--) { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 506 | int n = mIsRtl ? numChildren - 1 - i : i; |
| 507 | final View child = getChildAt(n); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 508 | if (child.getLeft() <= galleryRight) { |
| 509 | break; |
| 510 | } else { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 511 | start = n; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 512 | count++; |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 513 | mRecycler.put(firstPosition + n, child); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 514 | } |
| 515 | } |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 516 | if (mIsRtl) { |
| 517 | start = 0; |
| 518 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 519 | } |
| 520 | |
| 521 | detachViewsFromParent(start, count); |
| 522 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 523 | if (toLeft != mIsRtl) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 524 | mFirstPosition += count; |
| 525 | } |
| 526 | } |
| 527 | |
| 528 | /** |
| 529 | * Scrolls the items so that the selected item is in its 'slot' (its center |
| 530 | * is the gallery's center). |
| 531 | */ |
| 532 | private void scrollIntoSlots() { |
| 533 | |
| 534 | if (getChildCount() == 0 || mSelectedChild == null) return; |
| 535 | |
| 536 | int selectedCenter = getCenterOfView(mSelectedChild); |
| 537 | int targetCenter = getCenterOfGallery(); |
| 538 | |
| 539 | int scrollAmount = targetCenter - selectedCenter; |
| 540 | if (scrollAmount != 0) { |
| 541 | mFlingRunnable.startUsingDistance(scrollAmount); |
| 542 | } else { |
| 543 | onFinishedMovement(); |
| 544 | } |
| 545 | } |
| 546 | |
| 547 | private void onFinishedMovement() { |
| 548 | if (mSuppressSelectionChanged) { |
| 549 | mSuppressSelectionChanged = false; |
| 550 | |
| 551 | // We haven't been callbacking during the fling, so do it now |
| 552 | super.selectionChanged(); |
| 553 | } |
Adam Powell | 4e8510b | 2012-09-28 14:04:48 -0700 | [diff] [blame] | 554 | mSelectedCenterOffset = 0; |
Romain Guy | 8c11e31 | 2009-09-14 15:15:30 -0700 | [diff] [blame] | 555 | invalidate(); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 556 | } |
| 557 | |
| 558 | @Override |
| 559 | void selectionChanged() { |
| 560 | if (!mSuppressSelectionChanged) { |
| 561 | super.selectionChanged(); |
| 562 | } |
| 563 | } |
| 564 | |
| 565 | /** |
| 566 | * Looks for the child that is closest to the center and sets it as the |
| 567 | * selected child. |
| 568 | */ |
| 569 | private void setSelectionToCenterChild() { |
| 570 | |
| 571 | View selView = mSelectedChild; |
| 572 | if (mSelectedChild == null) return; |
| 573 | |
| 574 | int galleryCenter = getCenterOfGallery(); |
| 575 | |
Romain Guy | 8c11e31 | 2009-09-14 15:15:30 -0700 | [diff] [blame] | 576 | // Common case where the current selected position is correct |
| 577 | if (selView.getLeft() <= galleryCenter && selView.getRight() >= galleryCenter) { |
| 578 | return; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 579 | } |
| 580 | |
| 581 | // TODO better search |
| 582 | int closestEdgeDistance = Integer.MAX_VALUE; |
| 583 | int newSelectedChildIndex = 0; |
| 584 | for (int i = getChildCount() - 1; i >= 0; i--) { |
| 585 | |
| 586 | View child = getChildAt(i); |
| 587 | |
| 588 | if (child.getLeft() <= galleryCenter && child.getRight() >= galleryCenter) { |
| 589 | // This child is in the center |
| 590 | newSelectedChildIndex = i; |
| 591 | break; |
| 592 | } |
| 593 | |
| 594 | int childClosestEdgeDistance = Math.min(Math.abs(child.getLeft() - galleryCenter), |
| 595 | Math.abs(child.getRight() - galleryCenter)); |
| 596 | if (childClosestEdgeDistance < closestEdgeDistance) { |
| 597 | closestEdgeDistance = childClosestEdgeDistance; |
| 598 | newSelectedChildIndex = i; |
| 599 | } |
| 600 | } |
| 601 | |
| 602 | int newPos = mFirstPosition + newSelectedChildIndex; |
| 603 | |
| 604 | if (newPos != mSelectedPosition) { |
| 605 | setSelectedPositionInt(newPos); |
| 606 | setNextSelectedPositionInt(newPos); |
| 607 | checkSelectionChanged(); |
| 608 | } |
| 609 | } |
| 610 | |
| 611 | /** |
| 612 | * Creates and positions all views for this Gallery. |
| 613 | * <p> |
| 614 | * We layout rarely, most of the time {@link #trackMotionScroll(int)} takes |
| 615 | * care of repositioning, adding, and removing children. |
| 616 | * |
| 617 | * @param delta Change in the selected position. +1 means the selection is |
| 618 | * moving to the right, so views are scrolling to the left. -1 |
| 619 | * means the selection is moving to the left. |
| 620 | */ |
| 621 | @Override |
| 622 | void layout(int delta, boolean animate) { |
| 623 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 624 | mIsRtl = isLayoutRtl(); |
| 625 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 626 | int childrenLeft = mSpinnerPadding.left; |
| 627 | int childrenWidth = mRight - mLeft - mSpinnerPadding.left - mSpinnerPadding.right; |
| 628 | |
| 629 | if (mDataChanged) { |
| 630 | handleDataChanged(); |
| 631 | } |
| 632 | |
| 633 | // Handle an empty gallery by removing all views. |
| 634 | if (mItemCount == 0) { |
| 635 | resetList(); |
| 636 | return; |
| 637 | } |
| 638 | |
| 639 | // Update to the new selected position. |
| 640 | if (mNextSelectedPosition >= 0) { |
| 641 | setSelectedPositionInt(mNextSelectedPosition); |
| 642 | } |
| 643 | |
| 644 | // All views go in recycler while we are in layout |
| 645 | recycleAllViews(); |
| 646 | |
| 647 | // Clear out old views |
| 648 | //removeAllViewsInLayout(); |
| 649 | detachAllViewsFromParent(); |
| 650 | |
| 651 | /* |
| 652 | * These will be used to give initial positions to views entering the |
| 653 | * gallery as we scroll |
| 654 | */ |
| 655 | mRightMost = 0; |
| 656 | mLeftMost = 0; |
| 657 | |
| 658 | // Make selected view and center it |
| 659 | |
| 660 | /* |
| 661 | * mFirstPosition will be decreased as we add views to the left later |
| 662 | * on. The 0 for x will be offset in a couple lines down. |
| 663 | */ |
| 664 | mFirstPosition = mSelectedPosition; |
| 665 | View sel = makeAndAddView(mSelectedPosition, 0, 0, true); |
| 666 | |
| 667 | // Put the selected child in the center |
Adam Powell | 4e8510b | 2012-09-28 14:04:48 -0700 | [diff] [blame] | 668 | int selectedOffset = childrenLeft + (childrenWidth / 2) - (sel.getWidth() / 2) + |
| 669 | mSelectedCenterOffset; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 670 | sel.offsetLeftAndRight(selectedOffset); |
| 671 | |
| 672 | fillToGalleryRight(); |
| 673 | fillToGalleryLeft(); |
| 674 | |
| 675 | // Flush any cached views that did not get reused above |
| 676 | mRecycler.clear(); |
| 677 | |
| 678 | invalidate(); |
| 679 | checkSelectionChanged(); |
| 680 | |
| 681 | mDataChanged = false; |
| 682 | mNeedSync = false; |
| 683 | setNextSelectedPositionInt(mSelectedPosition); |
| 684 | |
| 685 | updateSelectedItemMetadata(); |
| 686 | } |
| 687 | |
| 688 | private void fillToGalleryLeft() { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 689 | if (mIsRtl) { |
| 690 | fillToGalleryLeftRtl(); |
| 691 | } else { |
| 692 | fillToGalleryLeftLtr(); |
| 693 | } |
| 694 | } |
| 695 | |
| 696 | private void fillToGalleryLeftRtl() { |
| 697 | int itemSpacing = mSpacing; |
| 698 | int galleryLeft = mPaddingLeft; |
| 699 | int numChildren = getChildCount(); |
| 700 | int numItems = mItemCount; |
| 701 | |
| 702 | // Set state for initial iteration |
| 703 | View prevIterationView = getChildAt(numChildren - 1); |
| 704 | int curPosition; |
| 705 | int curRightEdge; |
| 706 | |
| 707 | if (prevIterationView != null) { |
| 708 | curPosition = mFirstPosition + numChildren; |
| 709 | curRightEdge = prevIterationView.getLeft() - itemSpacing; |
| 710 | } else { |
| 711 | // No children available! |
| 712 | mFirstPosition = curPosition = mItemCount - 1; |
| 713 | curRightEdge = mRight - mLeft - mPaddingRight; |
| 714 | mShouldStopFling = true; |
| 715 | } |
| 716 | |
| 717 | while (curRightEdge > galleryLeft && curPosition < mItemCount) { |
| 718 | prevIterationView = makeAndAddView(curPosition, curPosition - mSelectedPosition, |
| 719 | curRightEdge, false); |
| 720 | |
| 721 | // Set state for next iteration |
| 722 | curRightEdge = prevIterationView.getLeft() - itemSpacing; |
| 723 | curPosition++; |
| 724 | } |
| 725 | } |
| 726 | |
| 727 | private void fillToGalleryLeftLtr() { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 728 | int itemSpacing = mSpacing; |
| 729 | int galleryLeft = mPaddingLeft; |
| 730 | |
| 731 | // Set state for initial iteration |
| 732 | View prevIterationView = getChildAt(0); |
| 733 | int curPosition; |
| 734 | int curRightEdge; |
| 735 | |
| 736 | if (prevIterationView != null) { |
| 737 | curPosition = mFirstPosition - 1; |
| 738 | curRightEdge = prevIterationView.getLeft() - itemSpacing; |
| 739 | } else { |
| 740 | // No children available! |
| 741 | curPosition = 0; |
| 742 | curRightEdge = mRight - mLeft - mPaddingRight; |
| 743 | mShouldStopFling = true; |
| 744 | } |
| 745 | |
| 746 | while (curRightEdge > galleryLeft && curPosition >= 0) { |
| 747 | prevIterationView = makeAndAddView(curPosition, curPosition - mSelectedPosition, |
| 748 | curRightEdge, false); |
| 749 | |
| 750 | // Remember some state |
| 751 | mFirstPosition = curPosition; |
| 752 | |
| 753 | // Set state for next iteration |
| 754 | curRightEdge = prevIterationView.getLeft() - itemSpacing; |
| 755 | curPosition--; |
| 756 | } |
| 757 | } |
| 758 | |
| 759 | private void fillToGalleryRight() { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 760 | if (mIsRtl) { |
| 761 | fillToGalleryRightRtl(); |
| 762 | } else { |
| 763 | fillToGalleryRightLtr(); |
| 764 | } |
| 765 | } |
| 766 | |
| 767 | private void fillToGalleryRightRtl() { |
| 768 | int itemSpacing = mSpacing; |
| 769 | int galleryRight = mRight - mLeft - mPaddingRight; |
| 770 | |
| 771 | // Set state for initial iteration |
| 772 | View prevIterationView = getChildAt(0); |
| 773 | int curPosition; |
| 774 | int curLeftEdge; |
| 775 | |
| 776 | if (prevIterationView != null) { |
| 777 | curPosition = mFirstPosition -1; |
| 778 | curLeftEdge = prevIterationView.getRight() + itemSpacing; |
| 779 | } else { |
| 780 | curPosition = 0; |
| 781 | curLeftEdge = mPaddingLeft; |
| 782 | mShouldStopFling = true; |
| 783 | } |
| 784 | |
| 785 | while (curLeftEdge < galleryRight && curPosition >= 0) { |
| 786 | prevIterationView = makeAndAddView(curPosition, curPosition - mSelectedPosition, |
| 787 | curLeftEdge, true); |
| 788 | |
| 789 | // Remember some state |
| 790 | mFirstPosition = curPosition; |
| 791 | |
| 792 | // Set state for next iteration |
| 793 | curLeftEdge = prevIterationView.getRight() + itemSpacing; |
| 794 | curPosition--; |
| 795 | } |
| 796 | } |
| 797 | |
| 798 | private void fillToGalleryRightLtr() { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 799 | int itemSpacing = mSpacing; |
| 800 | int galleryRight = mRight - mLeft - mPaddingRight; |
| 801 | int numChildren = getChildCount(); |
| 802 | int numItems = mItemCount; |
| 803 | |
| 804 | // Set state for initial iteration |
| 805 | View prevIterationView = getChildAt(numChildren - 1); |
| 806 | int curPosition; |
| 807 | int curLeftEdge; |
| 808 | |
| 809 | if (prevIterationView != null) { |
| 810 | curPosition = mFirstPosition + numChildren; |
| 811 | curLeftEdge = prevIterationView.getRight() + itemSpacing; |
| 812 | } else { |
| 813 | mFirstPosition = curPosition = mItemCount - 1; |
| 814 | curLeftEdge = mPaddingLeft; |
| 815 | mShouldStopFling = true; |
| 816 | } |
| 817 | |
| 818 | while (curLeftEdge < galleryRight && curPosition < numItems) { |
| 819 | prevIterationView = makeAndAddView(curPosition, curPosition - mSelectedPosition, |
| 820 | curLeftEdge, true); |
| 821 | |
| 822 | // Set state for next iteration |
| 823 | curLeftEdge = prevIterationView.getRight() + itemSpacing; |
| 824 | curPosition++; |
| 825 | } |
| 826 | } |
| 827 | |
| 828 | /** |
| 829 | * Obtain a view, either by pulling an existing view from the recycler or by |
| 830 | * getting a new one from the adapter. If we are animating, make sure there |
| 831 | * is enough information in the view's layout parameters to animate from the |
| 832 | * old to new positions. |
| 833 | * |
| 834 | * @param position Position in the gallery for the view to obtain |
| 835 | * @param offset Offset from the selected position |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 836 | * @param x X-coordinate indicating where this view should be placed. This |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 837 | * will either be the left or right edge of the view, depending on |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 838 | * the fromLeft parameter |
| 839 | * @param fromLeft Are we positioning views based on the left edge? (i.e., |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 840 | * building from left to right)? |
| 841 | * @return A view that has been added to the gallery |
| 842 | */ |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 843 | private View makeAndAddView(int position, int offset, int x, boolean fromLeft) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 844 | |
| 845 | View child; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 846 | if (!mDataChanged) { |
| 847 | child = mRecycler.get(position); |
| 848 | if (child != null) { |
| 849 | // Can reuse an existing view |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 850 | int childLeft = child.getLeft(); |
| 851 | |
| 852 | // Remember left and right edges of where views have been placed |
| 853 | mRightMost = Math.max(mRightMost, childLeft |
| 854 | + child.getMeasuredWidth()); |
| 855 | mLeftMost = Math.min(mLeftMost, childLeft); |
| 856 | |
| 857 | // Position the view |
| 858 | setUpChild(child, offset, x, fromLeft); |
| 859 | |
| 860 | return child; |
| 861 | } |
| 862 | } |
| 863 | |
| 864 | // Nothing found in the recycler -- ask the adapter for a view |
| 865 | child = mAdapter.getView(position, null, this); |
| 866 | |
| 867 | // Position the view |
| 868 | setUpChild(child, offset, x, fromLeft); |
| 869 | |
| 870 | return child; |
| 871 | } |
| 872 | |
| 873 | /** |
| 874 | * Helper for makeAndAddView to set the position of a view and fill out its |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 875 | * layout parameters. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 876 | * |
| 877 | * @param child The view to position |
| 878 | * @param offset Offset from the selected position |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 879 | * @param x X-coordinate indicating where this view should be placed. This |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 880 | * will either be the left or right edge of the view, depending on |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 881 | * the fromLeft parameter |
| 882 | * @param fromLeft Are we positioning views based on the left edge? (i.e., |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 883 | * building from left to right)? |
| 884 | */ |
| 885 | private void setUpChild(View child, int offset, int x, boolean fromLeft) { |
| 886 | |
| 887 | // Respect layout params that are already in the view. Otherwise |
| 888 | // make some up... |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 889 | Gallery.LayoutParams lp = (Gallery.LayoutParams) child.getLayoutParams(); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 890 | if (lp == null) { |
| 891 | lp = (Gallery.LayoutParams) generateDefaultLayoutParams(); |
| 892 | } |
| 893 | |
Chet Haase | bfea76c | 2012-12-11 14:02:55 -0800 | [diff] [blame] | 894 | addViewInLayout(child, fromLeft != mIsRtl ? -1 : 0, lp, true); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 895 | |
| 896 | child.setSelected(offset == 0); |
| 897 | |
| 898 | // Get measure specs |
| 899 | int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec, |
| 900 | mSpinnerPadding.top + mSpinnerPadding.bottom, lp.height); |
| 901 | int childWidthSpec = ViewGroup.getChildMeasureSpec(mWidthMeasureSpec, |
| 902 | mSpinnerPadding.left + mSpinnerPadding.right, lp.width); |
| 903 | |
| 904 | // Measure child |
| 905 | child.measure(childWidthSpec, childHeightSpec); |
| 906 | |
| 907 | int childLeft; |
| 908 | int childRight; |
| 909 | |
| 910 | // Position vertically based on gravity setting |
Romain Guy | 8c11e31 | 2009-09-14 15:15:30 -0700 | [diff] [blame] | 911 | int childTop = calculateTop(child, true); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 912 | int childBottom = childTop + child.getMeasuredHeight(); |
| 913 | |
| 914 | int width = child.getMeasuredWidth(); |
| 915 | if (fromLeft) { |
| 916 | childLeft = x; |
| 917 | childRight = childLeft + width; |
| 918 | } else { |
| 919 | childLeft = x - width; |
| 920 | childRight = x; |
| 921 | } |
| 922 | |
| 923 | child.layout(childLeft, childTop, childRight, childBottom); |
| 924 | } |
| 925 | |
| 926 | /** |
| 927 | * Figure out vertical placement based on mGravity |
| 928 | * |
| 929 | * @param child Child to place |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 930 | * @return Where the top of the child should be |
| 931 | */ |
Romain Guy | 8c11e31 | 2009-09-14 15:15:30 -0700 | [diff] [blame] | 932 | private int calculateTop(View child, boolean duringLayout) { |
Dianne Hackborn | 189ee18 | 2010-12-02 21:48:53 -0800 | [diff] [blame] | 933 | int myHeight = duringLayout ? getMeasuredHeight() : getHeight(); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 934 | int childHeight = duringLayout ? child.getMeasuredHeight() : child.getHeight(); |
| 935 | |
| 936 | int childTop = 0; |
| 937 | |
| 938 | switch (mGravity) { |
| 939 | case Gravity.TOP: |
| 940 | childTop = mSpinnerPadding.top; |
| 941 | break; |
| 942 | case Gravity.CENTER_VERTICAL: |
| 943 | int availableSpace = myHeight - mSpinnerPadding.bottom |
| 944 | - mSpinnerPadding.top - childHeight; |
| 945 | childTop = mSpinnerPadding.top + (availableSpace / 2); |
| 946 | break; |
| 947 | case Gravity.BOTTOM: |
| 948 | childTop = myHeight - mSpinnerPadding.bottom - childHeight; |
| 949 | break; |
| 950 | } |
| 951 | return childTop; |
| 952 | } |
| 953 | |
| 954 | @Override |
| 955 | public boolean onTouchEvent(MotionEvent event) { |
| 956 | |
| 957 | // Give everything to the gesture detector |
| 958 | boolean retValue = mGestureDetector.onTouchEvent(event); |
| 959 | |
| 960 | int action = event.getAction(); |
| 961 | if (action == MotionEvent.ACTION_UP) { |
| 962 | // Helper method for lifted finger |
| 963 | onUp(); |
| 964 | } else if (action == MotionEvent.ACTION_CANCEL) { |
| 965 | onCancel(); |
| 966 | } |
| 967 | |
| 968 | return retValue; |
| 969 | } |
| 970 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 971 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 972 | public boolean onSingleTapUp(MotionEvent e) { |
| 973 | |
| 974 | if (mDownTouchPosition >= 0) { |
| 975 | |
| 976 | // An item tap should make it selected, so scroll to this child. |
| 977 | scrollToChild(mDownTouchPosition - mFirstPosition); |
| 978 | |
| 979 | // Also pass the click so the client knows, if it wants to. |
| 980 | if (mShouldCallbackOnUnselectedItemClick || mDownTouchPosition == mSelectedPosition) { |
| 981 | performItemClick(mDownTouchView, mDownTouchPosition, mAdapter |
| 982 | .getItemId(mDownTouchPosition)); |
| 983 | } |
| 984 | |
| 985 | return true; |
| 986 | } |
| 987 | |
| 988 | return false; |
| 989 | } |
| 990 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 991 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 992 | public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { |
| 993 | |
| 994 | if (!mShouldCallbackDuringFling) { |
| 995 | // We want to suppress selection changes |
| 996 | |
| 997 | // Remove any future code to set mSuppressSelectionChanged = false |
| 998 | removeCallbacks(mDisableSuppressSelectionChangedRunnable); |
| 999 | |
| 1000 | // This will get reset once we scroll into slots |
| 1001 | if (!mSuppressSelectionChanged) mSuppressSelectionChanged = true; |
| 1002 | } |
| 1003 | |
| 1004 | // Fling the gallery! |
| 1005 | mFlingRunnable.startUsingVelocity((int) -velocityX); |
| 1006 | |
| 1007 | return true; |
| 1008 | } |
| 1009 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1010 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1011 | public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { |
| 1012 | |
| 1013 | if (localLOGV) Log.v(TAG, String.valueOf(e2.getX() - e1.getX())); |
| 1014 | |
| 1015 | /* |
| 1016 | * Now's a good time to tell our parent to stop intercepting our events! |
| 1017 | * The user has moved more than the slop amount, since GestureDetector |
| 1018 | * ensures this before calling this method. Also, if a parent is more |
| 1019 | * interested in this touch's events than we are, it would have |
| 1020 | * intercepted them by now (for example, we can assume when a Gallery is |
| 1021 | * in the ListView, a vertical scroll would not end up in this method |
| 1022 | * since a ListView would have intercepted it by now). |
| 1023 | */ |
| 1024 | mParent.requestDisallowInterceptTouchEvent(true); |
| 1025 | |
| 1026 | // As the user scrolls, we want to callback selection changes so related- |
| 1027 | // info on the screen is up-to-date with the gallery's selection |
| 1028 | if (!mShouldCallbackDuringFling) { |
| 1029 | if (mIsFirstScroll) { |
| 1030 | /* |
| 1031 | * We're not notifying the client of selection changes during |
| 1032 | * the fling, and this scroll could possibly be a fling. Don't |
| 1033 | * do selection changes until we're sure it is not a fling. |
| 1034 | */ |
| 1035 | if (!mSuppressSelectionChanged) mSuppressSelectionChanged = true; |
| 1036 | postDelayed(mDisableSuppressSelectionChangedRunnable, SCROLL_TO_FLING_UNCERTAINTY_TIMEOUT); |
| 1037 | } |
| 1038 | } else { |
| 1039 | if (mSuppressSelectionChanged) mSuppressSelectionChanged = false; |
| 1040 | } |
| 1041 | |
| 1042 | // Track the motion |
| 1043 | trackMotionScroll(-1 * (int) distanceX); |
| 1044 | |
| 1045 | mIsFirstScroll = false; |
| 1046 | return true; |
| 1047 | } |
| 1048 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1049 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1050 | public boolean onDown(MotionEvent e) { |
| 1051 | |
| 1052 | // Kill any existing fling/scroll |
| 1053 | mFlingRunnable.stop(false); |
| 1054 | |
| 1055 | // Get the item's view that was touched |
| 1056 | mDownTouchPosition = pointToPosition((int) e.getX(), (int) e.getY()); |
| 1057 | |
| 1058 | if (mDownTouchPosition >= 0) { |
| 1059 | mDownTouchView = getChildAt(mDownTouchPosition - mFirstPosition); |
| 1060 | mDownTouchView.setPressed(true); |
| 1061 | } |
| 1062 | |
| 1063 | // Reset the multiple-scroll tracking state |
| 1064 | mIsFirstScroll = true; |
| 1065 | |
| 1066 | // Must return true to get matching events for this down event. |
| 1067 | return true; |
| 1068 | } |
| 1069 | |
| 1070 | /** |
| 1071 | * Called when a touch event's action is MotionEvent.ACTION_UP. |
| 1072 | */ |
| 1073 | void onUp() { |
| 1074 | |
| 1075 | if (mFlingRunnable.mScroller.isFinished()) { |
| 1076 | scrollIntoSlots(); |
| 1077 | } |
| 1078 | |
| 1079 | dispatchUnpress(); |
| 1080 | } |
| 1081 | |
| 1082 | /** |
| 1083 | * Called when a touch event's action is MotionEvent.ACTION_CANCEL. |
| 1084 | */ |
| 1085 | void onCancel() { |
| 1086 | onUp(); |
| 1087 | } |
| 1088 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1089 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1090 | public void onLongPress(MotionEvent e) { |
| 1091 | |
| 1092 | if (mDownTouchPosition < 0) { |
| 1093 | return; |
| 1094 | } |
| 1095 | |
| 1096 | performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); |
| 1097 | long id = getItemIdAtPosition(mDownTouchPosition); |
| 1098 | dispatchLongPress(mDownTouchView, mDownTouchPosition, id); |
| 1099 | } |
| 1100 | |
| 1101 | // Unused methods from GestureDetector.OnGestureListener below |
| 1102 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1103 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1104 | public void onShowPress(MotionEvent e) { |
| 1105 | } |
| 1106 | |
| 1107 | // Unused methods from GestureDetector.OnGestureListener above |
| 1108 | |
| 1109 | private void dispatchPress(View child) { |
| 1110 | |
| 1111 | if (child != null) { |
| 1112 | child.setPressed(true); |
| 1113 | } |
| 1114 | |
| 1115 | setPressed(true); |
| 1116 | } |
| 1117 | |
| 1118 | private void dispatchUnpress() { |
| 1119 | |
| 1120 | for (int i = getChildCount() - 1; i >= 0; i--) { |
| 1121 | getChildAt(i).setPressed(false); |
| 1122 | } |
| 1123 | |
| 1124 | setPressed(false); |
| 1125 | } |
| 1126 | |
| 1127 | @Override |
| 1128 | public void dispatchSetSelected(boolean selected) { |
| 1129 | /* |
| 1130 | * We don't want to pass the selected state given from its parent to its |
| 1131 | * children since this widget itself has a selected state to give to its |
| 1132 | * children. |
| 1133 | */ |
| 1134 | } |
| 1135 | |
| 1136 | @Override |
| 1137 | protected void dispatchSetPressed(boolean pressed) { |
| 1138 | |
| 1139 | // Show the pressed state on the selected child |
| 1140 | if (mSelectedChild != null) { |
| 1141 | mSelectedChild.setPressed(pressed); |
| 1142 | } |
| 1143 | } |
| 1144 | |
| 1145 | @Override |
| 1146 | protected ContextMenuInfo getContextMenuInfo() { |
| 1147 | return mContextMenuInfo; |
| 1148 | } |
| 1149 | |
| 1150 | @Override |
| 1151 | public boolean showContextMenuForChild(View originalView) { |
| 1152 | |
| 1153 | final int longPressPosition = getPositionForView(originalView); |
| 1154 | if (longPressPosition < 0) { |
| 1155 | return false; |
| 1156 | } |
| 1157 | |
| 1158 | final long longPressId = mAdapter.getItemId(longPressPosition); |
| 1159 | return dispatchLongPress(originalView, longPressPosition, longPressId); |
| 1160 | } |
| 1161 | |
| 1162 | @Override |
| 1163 | public boolean showContextMenu() { |
| 1164 | |
| 1165 | if (isPressed() && mSelectedPosition >= 0) { |
| 1166 | int index = mSelectedPosition - mFirstPosition; |
| 1167 | View v = getChildAt(index); |
| 1168 | return dispatchLongPress(v, mSelectedPosition, mSelectedRowId); |
| 1169 | } |
| 1170 | |
| 1171 | return false; |
| 1172 | } |
| 1173 | |
| 1174 | private boolean dispatchLongPress(View view, int position, long id) { |
| 1175 | boolean handled = false; |
| 1176 | |
| 1177 | if (mOnItemLongClickListener != null) { |
| 1178 | handled = mOnItemLongClickListener.onItemLongClick(this, mDownTouchView, |
| 1179 | mDownTouchPosition, id); |
| 1180 | } |
| 1181 | |
| 1182 | if (!handled) { |
| 1183 | mContextMenuInfo = new AdapterContextMenuInfo(view, position, id); |
| 1184 | handled = super.showContextMenuForChild(this); |
| 1185 | } |
| 1186 | |
| 1187 | if (handled) { |
| 1188 | performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); |
| 1189 | } |
| 1190 | |
| 1191 | return handled; |
| 1192 | } |
| 1193 | |
| 1194 | @Override |
| 1195 | public boolean dispatchKeyEvent(KeyEvent event) { |
| 1196 | // Gallery steals all key events |
Christian Mehlmauer | 746a95a | 2010-05-17 21:16:20 +0200 | [diff] [blame] | 1197 | return event.dispatch(this, null, null); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1198 | } |
| 1199 | |
| 1200 | /** |
| 1201 | * Handles left, right, and clicking |
| 1202 | * @see android.view.View#onKeyDown |
| 1203 | */ |
| 1204 | @Override |
| 1205 | public boolean onKeyDown(int keyCode, KeyEvent event) { |
| 1206 | switch (keyCode) { |
| 1207 | |
| 1208 | case KeyEvent.KEYCODE_DPAD_LEFT: |
| 1209 | if (movePrevious()) { |
| 1210 | playSoundEffect(SoundEffectConstants.NAVIGATION_LEFT); |
David Sobreira Marques | c742c9f | 2012-03-07 18:57:32 -0500 | [diff] [blame] | 1211 | return true; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1212 | } |
David Sobreira Marques | c742c9f | 2012-03-07 18:57:32 -0500 | [diff] [blame] | 1213 | break; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1214 | case KeyEvent.KEYCODE_DPAD_RIGHT: |
| 1215 | if (moveNext()) { |
| 1216 | playSoundEffect(SoundEffectConstants.NAVIGATION_RIGHT); |
David Sobreira Marques | c742c9f | 2012-03-07 18:57:32 -0500 | [diff] [blame] | 1217 | return true; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1218 | } |
David Sobreira Marques | c742c9f | 2012-03-07 18:57:32 -0500 | [diff] [blame] | 1219 | break; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1220 | case KeyEvent.KEYCODE_DPAD_CENTER: |
| 1221 | case KeyEvent.KEYCODE_ENTER: |
| 1222 | mReceivedInvokeKeyDown = true; |
| 1223 | // fallthrough to default handling |
| 1224 | } |
| 1225 | |
| 1226 | return super.onKeyDown(keyCode, event); |
| 1227 | } |
| 1228 | |
| 1229 | @Override |
| 1230 | public boolean onKeyUp(int keyCode, KeyEvent event) { |
Michael Wright | 24d36f5 | 2013-07-19 15:55:14 -0700 | [diff] [blame] | 1231 | if (KeyEvent.isConfirmKey(keyCode)) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1232 | if (mReceivedInvokeKeyDown) { |
| 1233 | if (mItemCount > 0) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1234 | dispatchPress(mSelectedChild); |
| 1235 | postDelayed(new Runnable() { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1236 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1237 | public void run() { |
| 1238 | dispatchUnpress(); |
| 1239 | } |
| 1240 | }, ViewConfiguration.getPressedStateDuration()); |
Michael Wright | 24d36f5 | 2013-07-19 15:55:14 -0700 | [diff] [blame] | 1241 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1242 | int selectedIndex = mSelectedPosition - mFirstPosition; |
| 1243 | performItemClick(getChildAt(selectedIndex), mSelectedPosition, mAdapter |
| 1244 | .getItemId(mSelectedPosition)); |
| 1245 | } |
| 1246 | } |
Michael Wright | 24d36f5 | 2013-07-19 15:55:14 -0700 | [diff] [blame] | 1247 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1248 | // Clear the flag |
| 1249 | mReceivedInvokeKeyDown = false; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1250 | return true; |
| 1251 | } |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1252 | return super.onKeyUp(keyCode, event); |
| 1253 | } |
| 1254 | |
| 1255 | boolean movePrevious() { |
| 1256 | if (mItemCount > 0 && mSelectedPosition > 0) { |
| 1257 | scrollToChild(mSelectedPosition - mFirstPosition - 1); |
| 1258 | return true; |
| 1259 | } else { |
| 1260 | return false; |
| 1261 | } |
| 1262 | } |
| 1263 | |
| 1264 | boolean moveNext() { |
| 1265 | if (mItemCount > 0 && mSelectedPosition < mItemCount - 1) { |
| 1266 | scrollToChild(mSelectedPosition - mFirstPosition + 1); |
| 1267 | return true; |
| 1268 | } else { |
| 1269 | return false; |
| 1270 | } |
| 1271 | } |
| 1272 | |
| 1273 | private boolean scrollToChild(int childPosition) { |
| 1274 | View child = getChildAt(childPosition); |
| 1275 | |
| 1276 | if (child != null) { |
| 1277 | int distance = getCenterOfGallery() - getCenterOfView(child); |
| 1278 | mFlingRunnable.startUsingDistance(distance); |
| 1279 | return true; |
| 1280 | } |
| 1281 | |
| 1282 | return false; |
| 1283 | } |
| 1284 | |
| 1285 | @Override |
| 1286 | void setSelectedPositionInt(int position) { |
| 1287 | super.setSelectedPositionInt(position); |
| 1288 | |
| 1289 | // Updates any metadata we keep about the selected item. |
| 1290 | updateSelectedItemMetadata(); |
| 1291 | } |
| 1292 | |
| 1293 | private void updateSelectedItemMetadata() { |
| 1294 | |
| 1295 | View oldSelectedChild = mSelectedChild; |
| 1296 | |
| 1297 | View child = mSelectedChild = getChildAt(mSelectedPosition - mFirstPosition); |
| 1298 | if (child == null) { |
| 1299 | return; |
| 1300 | } |
| 1301 | |
| 1302 | child.setSelected(true); |
| 1303 | child.setFocusable(true); |
| 1304 | |
| 1305 | if (hasFocus()) { |
| 1306 | child.requestFocus(); |
| 1307 | } |
| 1308 | |
| 1309 | // We unfocus the old child down here so the above hasFocus check |
| 1310 | // returns true |
Romain Guy | 6691fcf | 2010-04-14 14:43:18 -0700 | [diff] [blame] | 1311 | if (oldSelectedChild != null && oldSelectedChild != child) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1312 | |
| 1313 | // Make sure its drawable state doesn't contain 'selected' |
| 1314 | oldSelectedChild.setSelected(false); |
| 1315 | |
| 1316 | // Make sure it is not focusable anymore, since otherwise arrow keys |
| 1317 | // can make this one be focused |
| 1318 | oldSelectedChild.setFocusable(false); |
| 1319 | } |
| 1320 | |
| 1321 | } |
| 1322 | |
| 1323 | /** |
| 1324 | * Describes how the child views are aligned. |
| 1325 | * @param gravity |
| 1326 | * |
| 1327 | * @attr ref android.R.styleable#Gallery_gravity |
| 1328 | */ |
| 1329 | public void setGravity(int gravity) |
| 1330 | { |
| 1331 | if (mGravity != gravity) { |
| 1332 | mGravity = gravity; |
| 1333 | requestLayout(); |
| 1334 | } |
| 1335 | } |
| 1336 | |
| 1337 | @Override |
| 1338 | protected int getChildDrawingOrder(int childCount, int i) { |
| 1339 | int selectedIndex = mSelectedPosition - mFirstPosition; |
| 1340 | |
| 1341 | // Just to be safe |
| 1342 | if (selectedIndex < 0) return i; |
| 1343 | |
| 1344 | if (i == childCount - 1) { |
| 1345 | // Draw the selected child last |
| 1346 | return selectedIndex; |
| 1347 | } else if (i >= selectedIndex) { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1348 | // Move the children after the selected child earlier one |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1349 | return i + 1; |
| 1350 | } else { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1351 | // Keep the children before the selected child the same |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1352 | return i; |
| 1353 | } |
| 1354 | } |
| 1355 | |
| 1356 | @Override |
| 1357 | protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { |
| 1358 | super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); |
| 1359 | |
| 1360 | /* |
| 1361 | * The gallery shows focus by focusing the selected item. So, give |
| 1362 | * focus to our selected item instead. We steal keys from our |
| 1363 | * selected item elsewhere. |
| 1364 | */ |
| 1365 | if (gainFocus && mSelectedChild != null) { |
| 1366 | mSelectedChild.requestFocus(direction); |
Romain Guy | 6691fcf | 2010-04-14 14:43:18 -0700 | [diff] [blame] | 1367 | mSelectedChild.setSelected(true); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1368 | } |
| 1369 | |
| 1370 | } |
| 1371 | |
Svetoslav Ganov | 8a78fd4 | 2012-01-17 14:36:46 -0800 | [diff] [blame] | 1372 | @Override |
| 1373 | public void onInitializeAccessibilityEvent(AccessibilityEvent event) { |
| 1374 | super.onInitializeAccessibilityEvent(event); |
| 1375 | event.setClassName(Gallery.class.getName()); |
| 1376 | } |
| 1377 | |
| 1378 | @Override |
| 1379 | public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { |
| 1380 | super.onInitializeAccessibilityNodeInfo(info); |
| 1381 | info.setClassName(Gallery.class.getName()); |
Svetoslav Ganov | 48d1586 | 2012-05-15 10:10:00 -0700 | [diff] [blame] | 1382 | info.setScrollable(mItemCount > 1); |
Svetoslav Ganov | fb1e80a | 2012-05-16 17:33:19 -0700 | [diff] [blame] | 1383 | if (isEnabled()) { |
| 1384 | if (mItemCount > 0 && mSelectedPosition < mItemCount - 1) { |
| 1385 | info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD); |
| 1386 | } |
| 1387 | if (isEnabled() && mItemCount > 0 && mSelectedPosition > 0) { |
| 1388 | info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD); |
| 1389 | } |
Svetoslav Ganov | 48d1586 | 2012-05-15 10:10:00 -0700 | [diff] [blame] | 1390 | } |
| 1391 | } |
| 1392 | |
| 1393 | @Override |
| 1394 | public boolean performAccessibilityAction(int action, Bundle arguments) { |
| 1395 | if (super.performAccessibilityAction(action, arguments)) { |
| 1396 | return true; |
| 1397 | } |
| 1398 | switch (action) { |
| 1399 | case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: { |
Svetoslav Ganov | fb1e80a | 2012-05-16 17:33:19 -0700 | [diff] [blame] | 1400 | if (isEnabled() && mItemCount > 0 && mSelectedPosition < mItemCount - 1) { |
Svetoslav Ganov | 48d1586 | 2012-05-15 10:10:00 -0700 | [diff] [blame] | 1401 | final int currentChildIndex = mSelectedPosition - mFirstPosition; |
| 1402 | return scrollToChild(currentChildIndex + 1); |
| 1403 | } |
| 1404 | } return false; |
| 1405 | case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: { |
Svetoslav Ganov | fb1e80a | 2012-05-16 17:33:19 -0700 | [diff] [blame] | 1406 | if (isEnabled() && mItemCount > 0 && mSelectedPosition > 0) { |
Svetoslav Ganov | 48d1586 | 2012-05-15 10:10:00 -0700 | [diff] [blame] | 1407 | final int currentChildIndex = mSelectedPosition - mFirstPosition; |
| 1408 | return scrollToChild(currentChildIndex - 1); |
| 1409 | } |
| 1410 | } return false; |
| 1411 | } |
| 1412 | return false; |
Svetoslav Ganov | 8a78fd4 | 2012-01-17 14:36:46 -0800 | [diff] [blame] | 1413 | } |
| 1414 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1415 | /** |
| 1416 | * Responsible for fling behavior. Use {@link #startUsingVelocity(int)} to |
| 1417 | * initiate a fling. Each frame of the fling is handled in {@link #run()}. |
| 1418 | * A FlingRunnable will keep re-posting itself until the fling is done. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1419 | */ |
| 1420 | private class FlingRunnable implements Runnable { |
| 1421 | /** |
| 1422 | * Tracks the decay of a fling scroll |
| 1423 | */ |
| 1424 | private Scroller mScroller; |
| 1425 | |
| 1426 | /** |
| 1427 | * X value reported by mScroller on the previous fling |
| 1428 | */ |
| 1429 | private int mLastFlingX; |
| 1430 | |
| 1431 | public FlingRunnable() { |
| 1432 | mScroller = new Scroller(getContext()); |
| 1433 | } |
| 1434 | |
| 1435 | private void startCommon() { |
| 1436 | // Remove any pending flings |
| 1437 | removeCallbacks(this); |
| 1438 | } |
| 1439 | |
| 1440 | public void startUsingVelocity(int initialVelocity) { |
| 1441 | if (initialVelocity == 0) return; |
| 1442 | |
| 1443 | startCommon(); |
| 1444 | |
| 1445 | int initialX = initialVelocity < 0 ? Integer.MAX_VALUE : 0; |
| 1446 | mLastFlingX = initialX; |
| 1447 | mScroller.fling(initialX, 0, initialVelocity, 0, |
| 1448 | 0, Integer.MAX_VALUE, 0, Integer.MAX_VALUE); |
| 1449 | post(this); |
| 1450 | } |
| 1451 | |
| 1452 | public void startUsingDistance(int distance) { |
| 1453 | if (distance == 0) return; |
| 1454 | |
| 1455 | startCommon(); |
| 1456 | |
| 1457 | mLastFlingX = 0; |
| 1458 | mScroller.startScroll(0, 0, -distance, 0, mAnimationDuration); |
| 1459 | post(this); |
| 1460 | } |
| 1461 | |
| 1462 | public void stop(boolean scrollIntoSlots) { |
| 1463 | removeCallbacks(this); |
| 1464 | endFling(scrollIntoSlots); |
| 1465 | } |
| 1466 | |
| 1467 | private void endFling(boolean scrollIntoSlots) { |
| 1468 | /* |
| 1469 | * Force the scroller's status to finished (without setting its |
| 1470 | * position to the end) |
| 1471 | */ |
| 1472 | mScroller.forceFinished(true); |
| 1473 | |
| 1474 | if (scrollIntoSlots) scrollIntoSlots(); |
| 1475 | } |
| 1476 | |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1477 | @Override |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1478 | public void run() { |
| 1479 | |
| 1480 | if (mItemCount == 0) { |
| 1481 | endFling(true); |
| 1482 | return; |
| 1483 | } |
| 1484 | |
| 1485 | mShouldStopFling = false; |
| 1486 | |
| 1487 | final Scroller scroller = mScroller; |
| 1488 | boolean more = scroller.computeScrollOffset(); |
| 1489 | final int x = scroller.getCurrX(); |
| 1490 | |
| 1491 | // Flip sign to convert finger direction to list items direction |
| 1492 | // (e.g. finger moving down means list is moving towards the top) |
| 1493 | int delta = mLastFlingX - x; |
| 1494 | |
| 1495 | // Pretend that each frame of a fling scroll is a touch scroll |
| 1496 | if (delta > 0) { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1497 | // Moving towards the left. Use leftmost view as mDownTouchPosition |
| 1498 | mDownTouchPosition = mIsRtl ? (mFirstPosition + getChildCount() - 1) : |
| 1499 | mFirstPosition; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1500 | |
| 1501 | // Don't fling more than 1 screen |
| 1502 | delta = Math.min(getWidth() - mPaddingLeft - mPaddingRight - 1, delta); |
| 1503 | } else { |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1504 | // Moving towards the right. Use rightmost view as mDownTouchPosition |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1505 | int offsetToLast = getChildCount() - 1; |
Doug Felt | 3d0124f | 2011-07-14 13:55:11 -0700 | [diff] [blame] | 1506 | mDownTouchPosition = mIsRtl ? mFirstPosition : |
| 1507 | (mFirstPosition + getChildCount() - 1); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1508 | |
| 1509 | // Don't fling more than 1 screen |
| 1510 | delta = Math.max(-(getWidth() - mPaddingRight - mPaddingLeft - 1), delta); |
| 1511 | } |
| 1512 | |
| 1513 | trackMotionScroll(delta); |
| 1514 | |
| 1515 | if (more && !mShouldStopFling) { |
| 1516 | mLastFlingX = x; |
| 1517 | post(this); |
| 1518 | } else { |
| 1519 | endFling(true); |
| 1520 | } |
| 1521 | } |
| 1522 | |
| 1523 | } |
| 1524 | |
| 1525 | /** |
| 1526 | * Gallery extends LayoutParams to provide a place to hold current |
| 1527 | * Transformation information along with previous position/transformation |
| 1528 | * info. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1529 | */ |
| 1530 | public static class LayoutParams extends ViewGroup.LayoutParams { |
| 1531 | public LayoutParams(Context c, AttributeSet attrs) { |
| 1532 | super(c, attrs); |
| 1533 | } |
| 1534 | |
| 1535 | public LayoutParams(int w, int h) { |
| 1536 | super(w, h); |
| 1537 | } |
| 1538 | |
| 1539 | public LayoutParams(ViewGroup.LayoutParams source) { |
| 1540 | super(source); |
| 1541 | } |
| 1542 | } |
| 1543 | } |