dali-toolkit/internal/controls/scrollable/item-view/item-view-impl.cpp

   1 /*
   2  * Copyright (c) 2014 Samsung Electronics Co., Ltd.
   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
  18 // CLASS HEADER
  19 #include <dali-toolkit/internal/controls/scrollable/item-view/item-view-impl.h>
  20
  21 // EXTERNAL INCLUDES
  22 #include <algorithm>
  23 #include <dali/public-api/animation/active-constraint.h>
  24 #include <dali/public-api/animation/constraint.h>
  25 #include <dali/public-api/animation/constraints.h>
  26 #include <dali/public-api/common/set-wrapper.h>
  27 #include <dali/public-api/common/stage.h>
  28 #include <dali/public-api/events/mouse-wheel-event.h>
  29 #include <dali/public-api/events/touch-event.h>
  30 #include <dali/public-api/object/type-registry.h>
  31
  32 // INTERNAL INCLUDES
  33 #include <dali-toolkit/public-api/controls/scrollable/item-view/item-factory.h>
  34 #include <dali-toolkit/internal/controls/scrollable/scroll-connector-impl.h>
  35
  36 using std::string;
  37 using std::set;
  38 using namespace Dali;
  39
  40 namespace // unnamed namespace
  41 {
  42
  43 //Type registration
  44 TypeRegistration mType( typeid(Toolkit::ItemView), typeid(Toolkit::Scrollable), NULL );
  45
  46 const float DEFAULT_MINIMUM_SWIPE_SPEED = 1.0f;
  47 const float DEFAULT_MINIMUM_SWIPE_DISTANCE = 3.0f;
  48 const float DEFAULT_MOUSE_WHEEL_SCROLL_DISTANCE_STEP_PROPORTION = 0.1f;
  49
  50 const float DEFAULT_MINIMUM_SWIPE_DURATION = 0.45f;
  51 const float DEFAULT_MAXIMUM_SWIPE_DURATION = 2.6f;
  52
  53 const float DEFAULT_REFRESH_INTERVAL_LAYOUT_POSITIONS = 20.0f; // 1 updates per 20 items
  54 const int MOUSE_WHEEL_EVENT_FINISHED_TIME_OUT = 500;  // 0.5 second
  55
  56 const float DEFAULT_ANCHORING_DURATION = 1.0f;  // 1 second
  57
  58 const float MILLISECONDS_PER_SECONDS = 1000.0f;
  59
  60 const Vector2 OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE( 720.0f, 42.0f );
  61 const float OVERSHOOT_BOUNCE_ACTOR_RESIZE_THRESHOLD = 180.0f;
  62 const Vector4 OVERSHOOT_OVERLAY_NINE_PATCH_BORDER(0.0f, 0.0f, 1.0f, 12.0f);
  63 const float DEFAULT_KEYBOARD_FOCUS_SCROLL_DURATION = 0.2f;
  64
  65 const string LAYOUT_POSITION_PROPERTY_NAME( "item-view-layout-position" );
  66 const string POSITION_PROPERTY_NAME( "item-view-position" );
  67 const string MINIMUM_LAYOUT_POSITION_PROPERTY_NAME( "item-view-minimum-layout-position" );
  68 const string SCROLL_SPEED_PROPERTY_NAME( "item-view-scroll-speed" );
  69 const string SCROLL_DIRECTION_PROPERTY_NAME( "item-view-scroll-direction" );
  70 const string OVERSHOOT_PROPERTY_NAME( "item-view-overshoot" );
  71
  72 /**
  73  * Local helper to convert pan distance (in actor coordinates) to the layout-specific scrolling direction
  74  */
  75 float CalculateScrollDistance(Vector2 panDistance, Toolkit::ItemLayout& layout)
  76 {
  77   Radian scrollDirection(layout.GetScrollDirection());
  78
  79   float cosTheta = cosf(scrollDirection);
  80   float sinTheta = sinf(scrollDirection);
  81
  82   return panDistance.x * sinTheta + panDistance.y * cosTheta;
  83 }
  84
  85 // Overshoot overlay constraints
  86
  87 struct OvershootOverlaySizeConstraint
  88 {
  89   Vector3 operator()(const Vector3& current,
  90                      const PropertyInput& parentScrollDirectionProperty,
  91                      const PropertyInput& parentOvershootProperty,
  92                      const PropertyInput& parentSizeProperty)
  93   {
  94     const Vector3 parentScrollDirection = parentScrollDirectionProperty.GetVector3();
  95     const Vector3 parentSize = parentSizeProperty.GetVector3();
  96     const Toolkit::ControlOrientation::Type& parentOrientation = static_cast<Toolkit::ControlOrientation::Type>(parentScrollDirection.z);
  97
  98     float overlayWidth;
  99
 100     if(Toolkit::IsVertical(parentOrientation))
 101     {
 102       overlayWidth = fabsf(parentScrollDirection.y) > Math::MACHINE_EPSILON_1 ? parentSize.x : parentSize.y;
 103     }
 104     else
 105     {
 106       overlayWidth = fabsf(parentScrollDirection.x) > Math::MACHINE_EPSILON_1 ? parentSize.y : parentSize.x;
 107     }
 108
 109     float overlayHeight = (overlayWidth > OVERSHOOT_BOUNCE_ACTOR_RESIZE_THRESHOLD) ? OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height : OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height*0.5f;
 110
 111     return Vector3( overlayWidth, overlayHeight, current.depth );
 112   }
 113 };
 114
 115 struct OvershootOverlayRotationConstraint
 116 {
 117   Quaternion operator()(const Quaternion& current,
 118                         const PropertyInput& parentScrollDirectionProperty,
 119                         const PropertyInput& parentOvershootProperty)
 120   {
 121     const Vector3 parentScrollDirection = parentScrollDirectionProperty.GetVector3();
 122     const float parentOvershoot = parentOvershootProperty.GetFloat();
 123     const Toolkit::ControlOrientation::Type& parentOrientation = static_cast<Toolkit::ControlOrientation::Type>(parentScrollDirection.z);
 124
 125     Quaternion rotation;
 126
 127     if(Toolkit::IsVertical(parentOrientation))
 128     {
 129       if(fabsf(parentScrollDirection.y) <= Math::MACHINE_EPSILON_1)
 130       {
 131         if( (parentOrientation == Toolkit::ControlOrientation::Up && parentOvershoot < Math::MACHINE_EPSILON_0)
 132             || (parentOrientation == Toolkit::ControlOrientation::Down && parentOvershoot > Math::MACHINE_EPSILON_0) )
 133         {
 134           rotation = Quaternion(0.5f * Math::PI, Vector3::ZAXIS);
 135         }
 136         else
 137         {
 138           rotation = Quaternion(1.5f * Math::PI, Vector3::ZAXIS);
 139         }
 140       }
 141       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.y > Math::MACHINE_EPSILON_0)
 142             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.y < Math::MACHINE_EPSILON_0) )
 143       {
 144         rotation = Quaternion(0.0f, Vector3::ZAXIS);
 145       }
 146       else
 147       {
 148         rotation = Quaternion(Math::PI, Vector3::ZAXIS);
 149       }
 150     }
 151     else
 152     {
 153       if(fabsf(parentScrollDirection.x) <= Math::MACHINE_EPSILON_1)
 154       {
 155         if( (parentOrientation == Toolkit::ControlOrientation::Left && parentOvershoot > Math::MACHINE_EPSILON_0)
 156             ||(parentOrientation == Toolkit::ControlOrientation::Right && parentOvershoot < Math::MACHINE_EPSILON_0) )
 157         {
 158           rotation = Quaternion(Math::PI, Vector3::ZAXIS);
 159         }
 160         else
 161         {
 162           rotation = Quaternion(0.0f, Vector3::ZAXIS);
 163         }
 164       }
 165       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.x > Math::MACHINE_EPSILON_0)
 166             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.x < Math::MACHINE_EPSILON_0) )
 167       {
 168         rotation = Quaternion(1.5f * Math::PI, Vector3::ZAXIS);
 169       }
 170       else
 171       {
 172         rotation = Quaternion(0.5f * Math::PI, Vector3::ZAXIS);
 173       }
 174     }
 175
 176     return rotation;
 177   }
 178 };
 179
 180 struct OvershootOverlayPositionConstraint
 181 {
 182   Vector3 operator()(const Vector3&    current,
 183                      const PropertyInput& parentSizeProperty,
 184                      const PropertyInput& parentScrollDirectionProperty,
 185                      const PropertyInput& parentOvershootProperty)
 186   {
 187     const Vector3 parentScrollDirection = parentScrollDirectionProperty.GetVector3();
 188     const float parentOvershoot = parentOvershootProperty.GetFloat();
 189     const Vector3 parentSize = parentSizeProperty.GetVector3();
 190     const Toolkit::ControlOrientation::Type& parentOrientation = static_cast<Toolkit::ControlOrientation::Type>(parentScrollDirection.z);
 191
 192     Vector3 relativeOffset;
 193
 194     if(Toolkit::IsVertical(parentOrientation))
 195     {
 196       if(fabsf(parentScrollDirection.y) <= Math::MACHINE_EPSILON_1)
 197       {
 198         if( (parentOrientation == Toolkit::ControlOrientation::Up && parentOvershoot < Math::MACHINE_EPSILON_0)
 199             || (parentOrientation == Toolkit::ControlOrientation::Down && parentOvershoot > Math::MACHINE_EPSILON_0) )
 200         {
 201           relativeOffset = Vector3(1.0f, 0.0f, 0.0f);
 202         }
 203         else
 204         {
 205           relativeOffset =Vector3(0.0f, 1.0f, 0.0f);
 206         }
 207       }
 208       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.y > Math::MACHINE_EPSILON_0)
 209             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.y < Math::MACHINE_EPSILON_0) )
 210       {
 211         relativeOffset = Vector3(0.0f, 0.0f, 0.0f);
 212       }
 213       else
 214       {
 215         relativeOffset = Vector3(1.0f, 1.0f, 0.0f);
 216       }
 217     }
 218     else
 219     {
 220       if(fabsf(parentScrollDirection.x) <= Math::MACHINE_EPSILON_1)
 221       {
 222         if( (parentOrientation == Toolkit::ControlOrientation::Left && parentOvershoot < Math::MACHINE_EPSILON_0)
 223             || (parentOrientation == Toolkit::ControlOrientation::Right && parentOvershoot > Math::MACHINE_EPSILON_0) )
 224         {
 225           relativeOffset = Vector3(0.0f, 0.0f, 0.0f);
 226         }
 227         else
 228         {
 229           relativeOffset = Vector3(1.0f, 1.0f, 0.0f);
 230         }
 231       }
 232       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.x > Math::MACHINE_EPSILON_0)
 233             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.x < Math::MACHINE_EPSILON_0) )
 234       {
 235         relativeOffset = Vector3(0.0f, 1.0f, 0.0f);
 236       }
 237       else
 238       {
 239         relativeOffset = Vector3(1.0f, 0.0f, 0.0f);
 240       }
 241     }
 242
 243     return relativeOffset * parentSize;
 244
 245   }
 246 };
 247
 248 struct OvershootOverlayVisibilityConstraint
 249 {
 250   bool operator()(const bool& current,
 251                   const PropertyInput& parentLayoutScrollableProperty)
 252   {
 253     const bool parentLayoutScrollable = parentLayoutScrollableProperty.GetBoolean();
 254
 255     return parentLayoutScrollable;
 256   }
 257 };
 258
 259 /**
 260  * Relative position Constraint
 261  * Generates the relative position value of the item view based on the layout position,
 262  * and it's relation to the layout domain. This is a value from 0.0f to 1.0f in each axis.
 263  */
 264 Vector3 RelativePositionConstraint(const Vector3& current,
 265                                    const PropertyInput& scrollPositionProperty,
 266                                    const PropertyInput& scrollMinProperty,
 267                                    const PropertyInput& scrollMaxProperty,
 268                                    const PropertyInput& layoutSizeProperty)
 269 {
 270   const Vector3& position = Vector3(0.0f, scrollPositionProperty.GetFloat(), 0.0f);
 271   const Vector3& min = scrollMinProperty.GetVector3();
 272   const Vector3& max = scrollMaxProperty.GetVector3();
 273
 274   Vector3 relativePosition;
 275   Vector3 domainSize = max - min;
 276
 277   relativePosition.x = fabsf(domainSize.x) > Math::MACHINE_EPSILON_1 ? ((min.x - position.x) / fabsf(domainSize.x)) : 0.0f;
 278   relativePosition.y = fabsf(domainSize.y) > Math::MACHINE_EPSILON_1 ? ((min.y - position.y) / fabsf(domainSize.y)) : 0.0f;
 279
 280   return relativePosition;
 281 }
 282
 283 } // unnamed namespace
 284
 285 namespace Dali
 286 {
 287
 288 namespace Toolkit
 289 {
 290
 291 namespace Internal
 292 {
 293
 294 namespace // unnamed namespace
 295 {
 296
 297 bool FindById( const ItemContainer& items, ItemId id )
 298 {
 299   for( ConstItemIter iter = items.begin(); items.end() != iter; ++iter )
 300   {
 301     if( iter->first == id )
 302     {
 303       return true;
 304     }
 305   }
 306
 307   return false;
 308 }
 309
 310 } // unnamed namespace
 311
 312 Dali::Toolkit::ItemView ItemView::New(ItemFactory& factory)
 313 {
 314   // Create the implementation
 315   ItemViewPtr itemView(new ItemView(factory));
 316
 317   // Pass ownership to CustomActor via derived handle
 318   Dali::Toolkit::ItemView handle(*itemView);
 319
 320   // Second-phase init of the implementation
 321   // This can only be done after the CustomActor connection has been made...
 322   itemView->Initialize();
 323
 324   return handle;
 325 }
 326
 327 ItemView::ItemView(ItemFactory& factory)
 328 : Scrollable(),
 329   mItemFactory(factory),
 330   mActiveLayout(NULL),
 331   mAnimatingOvershootOn(false),
 332   mAnimateOvershootOff(false),
 333   mAnchoringEnabled(true),
 334   mAnchoringDuration(DEFAULT_ANCHORING_DURATION),
 335   mRefreshIntervalLayoutPositions(0.0f),
 336   mRefreshOrderHint(true/*Refresh item 0 first*/),
 337   mMinimumSwipeSpeed(DEFAULT_MINIMUM_SWIPE_SPEED),
 338   mMinimumSwipeDistance(DEFAULT_MINIMUM_SWIPE_DISTANCE),
 339   mMouseWheelScrollDistanceStep(0.0f),
 340   mScrollDistance(0.0f),
 341   mScrollSpeed(0.0f),
 342   mTotalPanDisplacement(Vector2::ZERO),
 343   mScrollOvershoot(0.0f),
 344   mIsFlicking(false),
 345   mGestureState(Gesture::Clear),
 346   mAddingItems(false),
 347   mPropertyPosition(Property::INVALID_INDEX),
 348   mPropertyMinimumLayoutPosition(Property::INVALID_INDEX),
 349   mPropertyScrollSpeed(Property::INVALID_INDEX),
 350   mRefreshEnabled(true),
 351   mItemsParentOrigin( ParentOrigin::CENTER),
 352   mItemsAnchorPoint( AnchorPoint::CENTER)
 353 {
 354   SetRequiresMouseWheelEvents(true);
 355   SetKeyboardNavigationSupport(true);
 356 }
 357
 358 void ItemView::OnInitialize()
 359 {
 360   SetSizePolicy( Toolkit::Control::Fixed, Toolkit::Control::Fixed );
 361
 362   RegisterCommonProperties();
 363
 364   Actor self = Self();
 365
 366   mScrollConnector = Dali::Toolkit::ScrollConnector::New();
 367   mScrollPositionObject = mScrollConnector.GetScrollPositionObject();
 368   mScrollConnector.ScrollPositionChangedSignal().Connect( this, &ItemView::OnScrollPositionChanged );
 369
 370   mPropertyMinimumLayoutPosition = self.RegisterProperty(MINIMUM_LAYOUT_POSITION_PROPERTY_NAME, 0.0f);
 371   mPropertyPosition = self.RegisterProperty(POSITION_PROPERTY_NAME, 0.0f);
 372   mPropertyScrollSpeed = self.RegisterProperty(SCROLL_SPEED_PROPERTY_NAME, 0.0f);
 373
 374   EnableScrollComponent(Toolkit::Scrollable::OvershootIndicator);
 375
 376   Constraint constraint = Constraint::New<Vector3>(mPropertyRelativePosition,
 377                                                    LocalSource(mPropertyPosition),
 378                                                    LocalSource(mPropertyPositionMin),
 379                                                    LocalSource(mPropertyPositionMax),
 380                                                    LocalSource(Actor::Property::Size),
 381                                                    RelativePositionConstraint);
 382   self.ApplyConstraint(constraint);
 383
 384   Vector2 stageSize = Stage::GetCurrent().GetSize();
 385   mMouseWheelScrollDistanceStep = stageSize.y * DEFAULT_MOUSE_WHEEL_SCROLL_DISTANCE_STEP_PROPORTION;
 386
 387   EnableGestureDetection(Gesture::Type(Gesture::Pan));
 388
 389   mMouseWheelEventFinishedTimer = Timer::New( MOUSE_WHEEL_EVENT_FINISHED_TIME_OUT );
 390   mMouseWheelEventFinishedTimer.TickSignal().Connect( this, &ItemView::OnMouseWheelEventFinished );
 391
 392   SetRefreshInterval(DEFAULT_REFRESH_INTERVAL_LAYOUT_POSITIONS);
 393 }
 394
 395 ItemView::~ItemView()
 396 {
 397 }
 398
 399 Dali::Toolkit::ScrollConnector ItemView::GetScrollConnector() const
 400 {
 401   return mScrollConnector;
 402 }
 403
 404 unsigned int ItemView::GetLayoutCount() const
 405 {
 406   return mLayouts.size();
 407 }
 408
 409 void ItemView::AddLayout(ItemLayout& layout)
 410 {
 411   mLayouts.push_back(ItemLayoutPtr(&layout));
 412 }
 413
 414 void ItemView::RemoveLayout(unsigned int layoutIndex)
 415 {
 416   DALI_ASSERT_ALWAYS(layoutIndex < mLayouts.size());
 417
 418   if (mActiveLayout == mLayouts[layoutIndex].Get())
 419   {
 420     mActiveLayout = NULL;
 421   }
 422
 423   mLayouts.erase(mLayouts.begin() + layoutIndex);
 424 }
 425
 426 ItemLayoutPtr ItemView::GetLayout(unsigned int layoutIndex) const
 427 {
 428   return mLayouts[layoutIndex];
 429 }
 430
 431 ItemLayoutPtr ItemView::GetActiveLayout() const
 432 {
 433   return ItemLayoutPtr(mActiveLayout);
 434 }
 435
 436 float ItemView::GetCurrentLayoutPosition(unsigned int itemId) const
 437 {
 438   return mScrollConnector.GetScrollPosition() + static_cast<float>( itemId );
 439 }
 440
 441 void ItemView::ActivateLayout(unsigned int layoutIndex, const Vector3& targetSize, float durationSeconds)
 442 {
 443   DALI_ASSERT_ALWAYS(layoutIndex < mLayouts.size());
 444
 445   mRefreshEnabled = false;
 446
 447   Actor self = Self();
 448
 449   // The ItemView size should match the active layout size
 450   self.SetSize(targetSize);
 451   mActiveLayoutTargetSize = targetSize;
 452
 453   // Switch to the new layout
 454   mActiveLayout = mLayouts[layoutIndex].Get();
 455
 456   // Move the items to the new layout positions...
 457
 458   bool resizeAnimationNeeded(false);
 459   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 460   {
 461     unsigned int itemId = iter->first;
 462     Actor actor = iter->second;
 463
 464     // Remove constraints from previous layout
 465     actor.RemoveConstraints();
 466
 467     Vector3 size;
 468     if(mActiveLayout->GetItemSize(itemId, targetSize, size))
 469     {
 470       if( durationSeconds > 0.0f )
 471       {
 472         // Use a size animation
 473         if (!resizeAnimationNeeded)
 474         {
 475           resizeAnimationNeeded = true;
 476           RemoveAnimation(mResizeAnimation);
 477           mResizeAnimation = Animation::New(durationSeconds);
 478         }
 479
 480         // The layout provides its own resize animation
 481         mActiveLayout->GetResizeAnimation(mResizeAnimation, actor, size, durationSeconds);
 482       }
 483       else
 484       {
 485         // resize immediately
 486         actor.SetSize(size);
 487       }
 488     }
 489
 490     mActiveLayout->ApplyConstraints(actor, itemId, durationSeconds, mScrollPositionObject, Self() );
 491   }
 492
 493   if (resizeAnimationNeeded)
 494   {
 495     mResizeAnimation.Play();
 496   }
 497
 498   // Refresh the new layout
 499   ItemRange range = GetItemRange(*mActiveLayout, targetSize, GetCurrentLayoutPosition(0), false/* don't reserve extra*/);
 500   AddActorsWithinRange( range, durationSeconds );
 501
 502   // Scroll to an appropriate layout position
 503
 504   bool scrollAnimationNeeded(false);
 505   float firstItemScrollPosition(0.0f);
 506
 507   float current = GetCurrentLayoutPosition(0);
 508   float minimum = ClampFirstItemPosition(current, targetSize, *mActiveLayout);
 509   self.SetProperty(mPropertyPosition, GetScrollPosition(current, targetSize));
 510
 511   if (current < minimum)
 512   {
 513     scrollAnimationNeeded = true;
 514     firstItemScrollPosition = minimum;
 515   }
 516   else if (mAnchoringEnabled)
 517   {
 518     scrollAnimationNeeded = true;
 519     firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(current);
 520   }
 521
 522   if (scrollAnimationNeeded)
 523   {
 524     RemoveAnimation(mScrollAnimation);
 525     mScrollAnimation = Animation::New(durationSeconds);
 526     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
 527     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, targetSize), AlphaFunctions::EaseOut );
 528     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnLayoutActivationScrollFinished);
 529     mScrollAnimation.Play();
 530   }
 531
 532   self.SetProperty(mPropertyMinimumLayoutPosition, mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize));
 533   AnimateScrollOvershoot(0.0f);
 534   mScrollOvershoot = 0.0f;
 535
 536   Radian scrollDirection(mActiveLayout->GetScrollDirection());
 537   float orientation = static_cast<float>(mActiveLayout->GetOrientation());
 538   self.SetProperty(mPropertyScrollDirection, Vector3(sinf(scrollDirection), cosf(scrollDirection), orientation));
 539
 540   self.SetProperty(mPropertyScrollSpeed, mScrollSpeed);
 541
 542   CalculateDomainSize(targetSize);
 543 }
 544
 545 void ItemView::DeactivateCurrentLayout()
 546 {
 547   if (mActiveLayout)
 548   {
 549     for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 550     {
 551       Actor actor = iter->second;
 552       actor.RemoveConstraints();
 553     }
 554
 555     mActiveLayout = NULL;
 556   }
 557 }
 558
 559 void ItemView::OnRefreshNotification(PropertyNotification& source)
 560 {
 561   if(mRefreshEnabled || mScrollAnimation)
 562   {
 563     // Only refresh the cache during normal scrolling
 564     DoRefresh(GetCurrentLayoutPosition(0), true);
 565   }
 566 }
 567
 568 void ItemView::DoRefresh(float currentLayoutPosition, bool cacheExtra)
 569 {
 570   if (mActiveLayout)
 571   {
 572     ItemRange range = GetItemRange(*mActiveLayout, mActiveLayoutTargetSize, currentLayoutPosition, cacheExtra/*reserve extra*/);
 573     RemoveActorsOutsideRange( range );
 574     AddActorsWithinRange( range, 0.0f/*immediate*/ );
 575
 576     mScrollUpdatedSignal.Emit( Vector3(0.0f, currentLayoutPosition, 0.0f) );
 577   }
 578 }
 579
 580 void ItemView::SetMinimumSwipeSpeed(float speed)
 581 {
 582   mMinimumSwipeSpeed = speed;
 583 }
 584
 585 float ItemView::GetMinimumSwipeSpeed() const
 586 {
 587   return mMinimumSwipeSpeed;
 588 }
 589
 590 void ItemView::SetMinimumSwipeDistance(float distance)
 591 {
 592   mMinimumSwipeDistance = distance;
 593 }
 594
 595 float ItemView::GetMinimumSwipeDistance() const
 596 {
 597   return mMinimumSwipeDistance;
 598 }
 599
 600 void ItemView::SetMouseWheelScrollDistanceStep(float step)
 601 {
 602   mMouseWheelScrollDistanceStep = step;
 603 }
 604
 605 float ItemView::GetMouseWheelScrollDistanceStep() const
 606 {
 607   return mMouseWheelScrollDistanceStep;
 608 }
 609
 610 void ItemView::SetAnchoring(bool enabled)
 611 {
 612   mAnchoringEnabled = enabled;
 613 }
 614
 615 bool ItemView::GetAnchoring() const
 616 {
 617   return mAnchoringEnabled;
 618 }
 619
 620 void ItemView::SetAnchoringDuration(float durationSeconds)
 621 {
 622   mAnchoringDuration = durationSeconds;
 623 }
 624
 625 float ItemView::GetAnchoringDuration() const
 626 {
 627   return mAnchoringDuration;
 628 }
 629
 630 void ItemView::SetRefreshInterval(float intervalLayoutPositions)
 631 {
 632   if( !Equals(mRefreshIntervalLayoutPositions, intervalLayoutPositions) )
 633   {
 634     mRefreshIntervalLayoutPositions = intervalLayoutPositions;
 635
 636     if(mRefreshNotification)
 637     {
 638       mScrollPositionObject.RemovePropertyNotification(mRefreshNotification);
 639     }
 640     mRefreshNotification = mScrollPositionObject.AddPropertyNotification( ScrollConnector::SCROLL_POSITION, StepCondition(mRefreshIntervalLayoutPositions, 0.0f) );
 641     mRefreshNotification.NotifySignal().Connect( this, &ItemView::OnRefreshNotification );
 642   }
 643 }
 644
 645 float ItemView::GetRefreshInterval() const
 646 {
 647   return mRefreshIntervalLayoutPositions;
 648 }
 649
 650 void ItemView::SetRefreshEnabled(bool enabled)
 651 {
 652   mRefreshEnabled = enabled;
 653 }
 654
 655 Actor ItemView::GetItem(unsigned int itemId) const
 656 {
 657   Actor actor;
 658
 659   ConstItemPoolIter iter = mItemPool.find( itemId );
 660   if( iter != mItemPool.end() )
 661   {
 662     actor = iter->second;
 663   }
 664
 665   return actor;
 666 }
 667
 668 unsigned int ItemView::GetItemId( Actor actor ) const
 669 {
 670   unsigned int itemId( 0 );
 671
 672   for ( ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter )
 673   {
 674     if( iter->second == actor )
 675     {
 676       itemId = iter->first;
 677       break;
 678     }
 679   }
 680
 681   return itemId;
 682 }
 683
 684 void ItemView::InsertItem( Item newItem, float durationSeconds )
 685 {
 686   mAddingItems = true;
 687
 688   Actor displacedActor;
 689   ItemPoolIter afterDisplacedIter = mItemPool.end();
 690
 691   ItemPoolIter foundIter = mItemPool.find( newItem.first );
 692   if( mItemPool.end() != foundIter )
 693   {
 694     SetupActor( newItem, durationSeconds );
 695     Self().Add( newItem.second );
 696
 697     displacedActor = foundIter->second;
 698     foundIter->second = newItem.second;
 699
 700     afterDisplacedIter = ++foundIter;
 701   }
 702   else
 703   {
 704     // Inserting before the existing item range?
 705     ItemPoolIter iter = mItemPool.begin();
 706     if( iter != mItemPool.end() &&
 707         iter->first > newItem.first )
 708     {
 709       displacedActor = iter->second;
 710       mItemPool.erase( iter++ ); // iter is still valid after the erase
 711
 712       afterDisplacedIter = iter;
 713     }
 714   }
 715
 716   if( displacedActor )
 717   {
 718     // Move the existing actors to make room
 719     for( ItemPoolIter iter = afterDisplacedIter; mItemPool.end() != iter; ++iter )
 720     {
 721       Actor temp = iter->second;
 722       iter->second = displacedActor;
 723       displacedActor = temp;
 724
 725       iter->second.RemoveConstraints();
 726       mActiveLayout->ApplyConstraints( iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 727     }
 728
 729     // Create last item
 730     ItemPool::reverse_iterator lastIter = mItemPool.rbegin();
 731     if ( lastIter != mItemPool.rend() )
 732     {
 733       ItemId lastId = lastIter->first;
 734       Item lastItem( lastId + 1, displacedActor );
 735       mItemPool.insert( lastItem );
 736
 737       lastItem.second.RemoveConstraints();
 738       mActiveLayout->ApplyConstraints( lastItem.second, lastItem.first, durationSeconds, mScrollPositionObject, Self() );
 739     }
 740   }
 741
 742   CalculateDomainSize(Self().GetCurrentSize());
 743
 744   mAddingItems = false;
 745 }
 746
 747 void ItemView::InsertItems( const ItemContainer& newItems, float durationSeconds )
 748 {
 749   mAddingItems = true;
 750
 751   // Insert from lowest id to highest
 752   std::set<Item> sortedItems;
 753   for( ConstItemIter iter = newItems.begin(); newItems.end() != iter; ++iter )
 754   {
 755     sortedItems.insert( *iter );
 756   }
 757
 758   for( std::set<Item>::iterator iter = sortedItems.begin(); sortedItems.end() != iter; ++iter )
 759   {
 760     Self().Add( iter->second );
 761
 762     ItemPoolIter foundIter = mItemPool.find( iter->first );
 763     if( mItemPool.end() != foundIter )
 764     {
 765       Actor moveMe = foundIter->second;
 766       foundIter->second = iter->second;
 767
 768       // Move the existing actors to make room
 769       for( ItemPoolIter iter = ++foundIter; mItemPool.end() != iter; ++iter )
 770       {
 771         Actor temp = iter->second;
 772         iter->second = moveMe;
 773         moveMe = temp;
 774       }
 775
 776       // Create last item
 777       ItemId lastId = mItemPool.rbegin()->first;
 778       Item lastItem( lastId + 1, moveMe );
 779       mItemPool.insert( lastItem );
 780     }
 781     else
 782     {
 783       mItemPool.insert( *iter );
 784     }
 785   }
 786
 787   // Relayout everything
 788   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 789   {
 790     // If newly inserted
 791     if( FindById( newItems, iter->first ) )
 792     {
 793       SetupActor( *iter, durationSeconds );
 794     }
 795     else
 796     {
 797       iter->second.RemoveConstraints();
 798       mActiveLayout->ApplyConstraints( iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 799     }
 800   }
 801
 802   CalculateDomainSize(Self().GetCurrentSize());
 803
 804   mAddingItems = false;
 805 }
 806
 807 void ItemView::RemoveItem( unsigned int itemId, float durationSeconds )
 808 {
 809   bool actorsReordered = RemoveActor( itemId );
 810   if( actorsReordered )
 811   {
 812     ReapplyAllConstraints( durationSeconds );
 813
 814     OnItemsRemoved();
 815   }
 816 }
 817
 818 void ItemView::RemoveItems( const ItemIdContainer& itemIds, float durationSeconds )
 819 {
 820   bool actorsReordered( false );
 821
 822   // Remove from highest id to lowest
 823   set<ItemId> sortedItems;
 824   for( ConstItemIdIter iter = itemIds.begin(); itemIds.end() != iter; ++iter )
 825   {
 826     sortedItems.insert( *iter );
 827   }
 828
 829   for( set<ItemId>::reverse_iterator iter = sortedItems.rbegin(); sortedItems.rend() != iter; ++iter )
 830   {
 831     if( RemoveActor( *iter ) )
 832     {
 833       actorsReordered = true;
 834     }
 835   }
 836
 837   if( actorsReordered )
 838   {
 839     ReapplyAllConstraints( durationSeconds );
 840
 841     OnItemsRemoved();
 842   }
 843 }
 844
 845 bool ItemView::RemoveActor(unsigned int itemId)
 846 {
 847   bool reordered( false );
 848
 849   ItemPoolIter removeIter = mItemPool.find( itemId );
 850   if( removeIter != mItemPool.end() )
 851   {
 852     ReleaseActor(itemId, removeIter->second);
 853   }
 854   else
 855   {
 856     // Removing before the existing item range?
 857     ItemPoolIter iter = mItemPool.begin();
 858     if( iter != mItemPool.end() &&
 859         iter->first > itemId )
 860     {
 861       // In order to decrement the first visible item ID
 862       mItemPool.insert( Item(iter->first - 1, Actor()) );
 863
 864       removeIter = mItemPool.begin();
 865     }
 866   }
 867
 868   if( removeIter != mItemPool.end() )
 869   {
 870     reordered = true;
 871
 872     // Adjust the remaining item IDs, for example if item 2 is removed:
 873     //   Initial actors:     After insert:
 874     //     ID 1 - ActorA       ID 1 - ActorA
 875     //     ID 2 - ActorB       ID 2 - ActorC (previously ID 3)
 876     //     ID 3 - ActorC       ID 3 - ActorB (previously ID 4)
 877     //     ID 4 - ActorD
 878     for (ItemPoolIter iter = removeIter; iter != mItemPool.end(); ++iter)
 879     {
 880       if( iter->first < mItemPool.rbegin()->first )
 881       {
 882         iter->second = mItemPool[ iter->first + 1 ];
 883       }
 884       else
 885       {
 886         mItemPool.erase( iter );
 887         break;
 888       }
 889     }
 890   }
 891
 892   return reordered;
 893 }
 894
 895 void ItemView::ReplaceItem( Item replacementItem, float durationSeconds )
 896 {
 897   mAddingItems = true;
 898
 899   SetupActor( replacementItem, durationSeconds );
 900   Self().Add( replacementItem.second );
 901
 902   const ItemPoolIter iter = mItemPool.find( replacementItem.first );
 903   if( mItemPool.end() != iter )
 904   {
 905     ReleaseActor(iter->first, iter->second);
 906     iter->second = replacementItem.second;
 907   }
 908   else
 909   {
 910     mItemPool.insert( replacementItem );
 911   }
 912
 913   CalculateDomainSize(Self().GetCurrentSize());
 914
 915   mAddingItems = false;
 916 }
 917
 918 void ItemView::ReplaceItems( const ItemContainer& replacementItems, float durationSeconds )
 919 {
 920   for( ConstItemIter iter = replacementItems.begin(); replacementItems.end() != iter; ++iter )
 921   {
 922     ReplaceItem( *iter, durationSeconds );
 923   }
 924 }
 925
 926 void ItemView::RemoveActorsOutsideRange( ItemRange range )
 927 {
 928   // Remove unwanted actors from the ItemView & ItemPool
 929   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); )
 930   {
 931     unsigned int current = iter->first;
 932
 933     if( ! range.Within( current ) )
 934     {
 935       ReleaseActor(iter->first, iter->second);
 936
 937       mItemPool.erase( iter++ ); // erase invalidates the return value of post-increment; iter remains valid
 938     }
 939     else
 940     {
 941       ++iter;
 942     }
 943   }
 944 }
 945
 946 void ItemView::AddActorsWithinRange( ItemRange range, float durationSeconds )
 947 {
 948   range.end = std::min(mItemFactory.GetNumberOfItems(), range.end);
 949
 950   // The order of addition depends on the scroll direction.
 951   if (mRefreshOrderHint)
 952   {
 953     for (unsigned int itemId = range.begin; itemId < range.end; ++itemId)
 954     {
 955       AddNewActor( itemId, durationSeconds );
 956     }
 957   }
 958   else
 959   {
 960     for (unsigned int itemId = range.end; itemId > range.begin; --itemId)
 961     {
 962       AddNewActor( itemId-1, durationSeconds );
 963     }
 964   }
 965
 966   // Total number of items may change dynamically.
 967   // Always recalculate the domain size to reflect that.
 968   CalculateDomainSize(Self().GetCurrentSize());
 969 }
 970
 971 void ItemView::AddNewActor( unsigned int itemId, float durationSeconds )
 972 {
 973   mAddingItems = true;
 974
 975   if( mItemPool.end() == mItemPool.find( itemId ) )
 976   {
 977     Actor actor = mItemFactory.NewItem( itemId );
 978
 979     if( actor )
 980     {
 981       Item newItem( itemId, actor );
 982
 983       mItemPool.insert( newItem );
 984
 985       SetupActor( newItem, durationSeconds );
 986       Self().Add( actor );
 987     }
 988   }
 989
 990   mAddingItems = false;
 991 }
 992
 993 void ItemView::SetupActor( Item item, float durationSeconds )
 994 {
 995   item.second.SetParentOrigin( mItemsParentOrigin );
 996   item.second.SetAnchorPoint( mItemsAnchorPoint );
 997
 998   if( mActiveLayout )
 999   {
1000     Vector3 size;
1001     if( mActiveLayout->GetItemSize( item.first, mActiveLayoutTargetSize, size ) )
1002     {
1003       item.second.SetSize( size );
1004     }
1005
1006     mActiveLayout->ApplyConstraints( item.second, item.first, durationSeconds, mScrollPositionObject, Self() );
1007   }
1008 }
1009
1010 void ItemView::ReleaseActor( ItemId item, Actor actor )
1011 {
1012   Self().Remove( actor );
1013   mItemFactory.ItemReleased(item, actor);
1014 }
1015
1016 ItemRange ItemView::GetItemRange(ItemLayout& layout, const Vector3& layoutSize, float layoutPosition, bool reserveExtra)
1017 {
1018   unsigned int itemCount = mItemFactory.GetNumberOfItems();
1019
1020   ItemRange available(0u, itemCount);
1021
1022   ItemRange range = layout.GetItemsWithinArea( layoutPosition, layoutSize );
1023
1024   if (reserveExtra)
1025   {
1026     // Add the reserve items for scrolling
1027     unsigned int extra = layout.GetReserveItemCount(layoutSize);
1028     range.begin = (range.begin >= extra) ? (range.begin - extra) : 0u;
1029     range.end += extra;
1030   }
1031
1032   return range.Intersection(available);
1033 }
1034
1035 void ItemView::OnChildAdd(Actor& child)
1036 {
1037   if(!mAddingItems)
1038   {
1039     // We don't want to do this downcast check for any item added by ItemView itself.
1040     Dali::Toolkit::ScrollComponent scrollComponent = Dali::Toolkit::ScrollComponent::DownCast(child);
1041     if(scrollComponent)
1042     {
1043       // Set the scroll connector when scroll bar is being added
1044       scrollComponent.SetScrollConnector(mScrollConnector);
1045     }
1046   }
1047 }
1048
1049 bool ItemView::OnTouchEvent(const TouchEvent& event)
1050 {
1051   // Ignore events with multiple-touch points
1052   if (event.GetPointCount() != 1)
1053   {
1054     return false;
1055   }
1056
1057   if (event.GetPoint(0).state == TouchPoint::Down)
1058   {
1059     // Cancel ongoing scrolling etc.
1060     mGestureState = Gesture::Clear;
1061
1062     mScrollDistance = 0.0f;
1063     mScrollSpeed = 0.0f;
1064     Self().SetProperty(mPropertyScrollSpeed, mScrollSpeed);
1065
1066     mScrollOvershoot = 0.0f;
1067     AnimateScrollOvershoot(0.0f);
1068
1069     if(mScrollAnimation)
1070     {
1071       mScrollCompletedSignal.Emit(GetCurrentScrollPosition());
1072     }
1073
1074     RemoveAnimation(mScrollAnimation);
1075   }
1076
1077   return true; // consume since we're potentially scrolling
1078 }
1079
1080 bool ItemView::OnMouseWheelEvent(const MouseWheelEvent& event)
1081 {
1082   // Respond the mouse wheel event to scroll
1083   if (mActiveLayout)
1084   {
1085     Actor self = Self();
1086     const Vector3 layoutSize = Self().GetCurrentSize();
1087     float layoutPositionDelta = GetCurrentLayoutPosition(0) - (event.z * mMouseWheelScrollDistanceStep * mActiveLayout->GetScrollSpeedFactor());
1088     float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1089
1090     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1091     self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1092     mScrollStartedSignal.Emit(GetCurrentScrollPosition());
1093     mRefreshEnabled = true;
1094   }
1095
1096   if (mMouseWheelEventFinishedTimer.IsRunning())
1097   {
1098     mMouseWheelEventFinishedTimer.Stop();
1099   }
1100
1101   mMouseWheelEventFinishedTimer.Start();
1102
1103   return true;
1104 }
1105
1106 bool ItemView::OnMouseWheelEventFinished()
1107 {
1108   if (mActiveLayout)
1109   {
1110     RemoveAnimation(mScrollAnimation);
1111
1112     // No more mouse wheel events coming. Do the anchoring if enabled.
1113     mScrollAnimation = DoAnchoring();
1114     if (mScrollAnimation)
1115     {
1116       mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1117       mScrollAnimation.Play();
1118     }
1119     else
1120     {
1121       mScrollOvershoot = 0.0f;
1122       AnimateScrollOvershoot(0.0f);
1123
1124       mScrollCompletedSignal.Emit(GetCurrentScrollPosition());
1125     }
1126   }
1127
1128   return false;
1129 }
1130
1131 void ItemView::ReapplyAllConstraints( float durationSeconds )
1132 {
1133   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1134   {
1135     unsigned int id = iter->first;
1136     Actor actor = iter->second;
1137
1138     actor.RemoveConstraints();
1139     mActiveLayout->ApplyConstraints(actor, id, durationSeconds, mScrollPositionObject, Self());
1140   }
1141 }
1142
1143 void ItemView::OnItemsRemoved()
1144 {
1145   CalculateDomainSize(Self().GetCurrentSize());
1146
1147   // Adjust scroll-position after an item is removed
1148   if( mActiveLayout )
1149   {
1150     float firstItemScrollPosition = ClampFirstItemPosition(GetCurrentLayoutPosition(0), Self().GetCurrentSize(), *mActiveLayout);
1151
1152     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1153   }
1154 }
1155
1156 float ItemView::ClampFirstItemPosition(float targetPosition, const Vector3& targetSize, ItemLayout& layout)
1157 {
1158   Actor self = Self();
1159   float minLayoutPosition = layout.GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize);
1160   float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, targetPosition));
1161   mScrollOvershoot = targetPosition - clamppedPosition;
1162   self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1163
1164   return clamppedPosition;
1165 }
1166
1167 void ItemView::OnPan( const PanGesture& gesture )
1168 {
1169   Actor self = Self();
1170   const Vector3 layoutSize = Self().GetCurrentSize();
1171
1172   RemoveAnimation(mScrollAnimation);
1173
1174   // Short-circuit if there is no active layout
1175   if (!mActiveLayout)
1176   {
1177     mGestureState = Gesture::Clear;
1178     return;
1179   }
1180
1181   mGestureState = gesture.state;
1182
1183   switch (mGestureState)
1184   {
1185     case Gesture::Finished:
1186     {
1187       // Swipe Detection
1188       if (fabsf(mScrollDistance) > mMinimumSwipeDistance &&
1189           mScrollSpeed > mMinimumSwipeSpeed)
1190       {
1191         float direction = (mScrollDistance < 0.0f) ? -1.0f : 1.0f;
1192
1193         mRefreshOrderHint = true;
1194
1195         float currentLayoutPosition = GetCurrentLayoutPosition(0);
1196         float firstItemScrollPosition = ClampFirstItemPosition(currentLayoutPosition + mScrollSpeed * direction,
1197                                                                layoutSize,
1198                                                                *mActiveLayout);
1199
1200         if (mAnchoringEnabled)
1201         {
1202           firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(firstItemScrollPosition);
1203         }
1204
1205         RemoveAnimation(mScrollAnimation);
1206
1207         float flickAnimationDuration = Clamp( mActiveLayout->GetItemFlickAnimationDuration() * std::max(1.0f, fabsf(firstItemScrollPosition - GetCurrentLayoutPosition(0)))
1208                                        , DEFAULT_MINIMUM_SWIPE_DURATION, DEFAULT_MAXIMUM_SWIPE_DURATION);
1209
1210         mScrollAnimation = Animation::New(flickAnimationDuration);
1211         mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1212         mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1213         mScrollAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1214
1215         mIsFlicking = true;
1216         // Check whether it has already scrolled to the end
1217         if(fabs(currentLayoutPosition - firstItemScrollPosition) > Math::MACHINE_EPSILON_0)
1218         {
1219           AnimateScrollOvershoot(0.0f);
1220         }
1221       }
1222
1223       // Anchoring may be triggered when there was no swipe
1224       if (!mScrollAnimation)
1225       {
1226         mScrollAnimation = DoAnchoring();
1227       }
1228
1229       // Reset the overshoot if no scroll animation.
1230       if (!mScrollAnimation)
1231       {
1232         mScrollCompletedSignal.Emit(GetCurrentScrollPosition());
1233
1234         AnimateScrollOvershoot(0.0f, false);
1235       }
1236     }
1237     break;
1238
1239     case Gesture::Started: // Fall through
1240     {
1241       mTotalPanDisplacement = Vector2::ZERO;
1242       mScrollStartedSignal.Emit(GetCurrentScrollPosition());
1243       mRefreshEnabled = true;
1244     }
1245
1246     case Gesture::Continuing:
1247     {
1248       mScrollDistance = CalculateScrollDistance(gesture.displacement, *mActiveLayout);
1249       mScrollSpeed = Clamp((gesture.GetSpeed() * gesture.GetSpeed() * mActiveLayout->GetFlickSpeedFactor() * MILLISECONDS_PER_SECONDS), 0.0f, mActiveLayout->GetMaximumSwipeSpeed());
1250
1251       // Refresh order depends on the direction of the scroll; negative is towards the last item.
1252       mRefreshOrderHint = mScrollDistance < 0.0f;
1253
1254       float layoutPositionDelta = GetCurrentLayoutPosition(0) + (mScrollDistance * mActiveLayout->GetScrollSpeedFactor());
1255
1256       float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1257
1258       float currentOvershoot = mScrollPositionObject.GetProperty<float>(ScrollConnector::OVERSHOOT);
1259
1260       mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1261       self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1262
1263       if( (firstItemScrollPosition >= 0.0f && currentOvershoot < 1.0f) || (firstItemScrollPosition <= mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), layoutSize) && currentOvershoot > -1.0f) )
1264       {
1265         mTotalPanDisplacement += gesture.displacement;
1266       }
1267
1268       mScrollOvershoot = CalculateScrollOvershoot();
1269       mScrollPositionObject.SetProperty( ScrollConnector::OVERSHOOT, mScrollOvershoot );
1270     }
1271     break;
1272
1273     case Gesture::Cancelled:
1274     {
1275       mScrollAnimation = DoAnchoring();
1276     }
1277     break;
1278
1279     default:
1280       break;
1281   }
1282
1283   if (mScrollAnimation)
1284   {
1285     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1286     mScrollAnimation.Play();
1287   }
1288 }
1289
1290 bool ItemView::OnAccessibilityPan(PanGesture gesture)
1291 {
1292   OnPan(gesture);
1293   return true;
1294 }
1295
1296 Actor ItemView::GetNextKeyboardFocusableActor(Actor actor, Toolkit::Control::KeyboardFocusNavigationDirection direction, bool loopEnabled)
1297 {
1298   Actor nextFocusActor;
1299   if(mActiveLayout)
1300   {
1301     int nextItemID = 0;
1302     if(!actor || actor == this->Self())
1303     {
1304       nextFocusActor = GetItem(nextItemID);
1305     }
1306     else if(actor && actor.GetParent() == this->Self())
1307     {
1308       int itemID = GetItemId(actor);
1309       nextItemID = mActiveLayout->GetNextFocusItemID(itemID, mItemFactory.GetNumberOfItems(), direction, loopEnabled);
1310       nextFocusActor = GetItem(nextItemID);
1311       if(nextFocusActor == actor)
1312       {
1313         // need to pass NULL actor back to focus manager
1314         nextFocusActor.Reset();
1315         return nextFocusActor;
1316       }
1317     }
1318     float layoutPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1319     Vector3 layoutSize = Self().GetCurrentSize();
1320     if(!nextFocusActor)
1321     {
1322       // likely the current item is not buffered, so not in our item pool, probably best to get first viewable item
1323       ItemRange viewableItems = mActiveLayout->GetItemsWithinArea(layoutPosition, layoutSize);
1324       nextItemID = viewableItems.begin;
1325       nextFocusActor = GetItem(nextItemID);
1326     }
1327   }
1328   return nextFocusActor;
1329 }
1330
1331 void ItemView::OnKeyboardFocusChangeCommitted(Actor commitedFocusableActor)
1332 {
1333   // only in this function if our chosen focus actor was actually used
1334   if(commitedFocusableActor)
1335   {
1336     int nextItemID = GetItemId(commitedFocusableActor);
1337     float layoutPosition = GetCurrentLayoutPosition(0);
1338     Vector3 layoutSize = Self().GetCurrentSize();
1339
1340     float scrollTo = mActiveLayout->GetClosestOnScreenLayoutPosition(nextItemID, layoutPosition, layoutSize);
1341     ScrollTo(Vector3(0.0f, scrollTo, 0.0f), DEFAULT_KEYBOARD_FOCUS_SCROLL_DURATION);
1342   }
1343 }
1344
1345 Animation ItemView::DoAnchoring()
1346 {
1347   Animation anchoringAnimation;
1348   Actor self = Self();
1349
1350   if (mActiveLayout && mAnchoringEnabled)
1351   {
1352     float anchorPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1353
1354     anchoringAnimation = Animation::New(mAnchoringDuration);
1355     anchoringAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), anchorPosition, AlphaFunctions::EaseOut );
1356     anchoringAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(anchorPosition, self.GetCurrentSize()), AlphaFunctions::EaseOut );
1357     anchoringAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1358     if(!mIsFlicking)
1359     {
1360       AnimateScrollOvershoot(0.0f);
1361     }
1362   }
1363
1364   return anchoringAnimation;
1365 }
1366
1367 void ItemView::OnScrollFinished(Animation& source)
1368 {
1369   Actor self = Self();
1370
1371   RemoveAnimation(mScrollAnimation); // mScrollAnimation is used to query whether we're scrolling
1372
1373   mScrollCompletedSignal.Emit(GetCurrentScrollPosition());
1374
1375   if(mIsFlicking && fabsf(mScrollOvershoot) > Math::MACHINE_EPSILON_1)
1376   {
1377     AnimateScrollOvershoot( mScrollOvershoot > 0.0f ? 1.0f : -1.0f, true);
1378   }
1379   else
1380   {
1381     // Reset the overshoot
1382     AnimateScrollOvershoot( 0.0f );
1383   }
1384   mIsFlicking = false;
1385
1386   mScrollOvershoot = 0.0f;
1387 }
1388
1389 void ItemView::OnLayoutActivationScrollFinished(Animation& source)
1390 {
1391   RemoveAnimation(mScrollAnimation);
1392   mRefreshEnabled = true;
1393   DoRefresh(GetCurrentLayoutPosition(0), true);
1394 }
1395
1396 void ItemView::OnOvershootOnFinished(Animation& animation)
1397 {
1398   mAnimatingOvershootOn = false;
1399   mScrollOvershootAnimation.FinishedSignal().Disconnect(this, &ItemView::OnOvershootOnFinished);
1400   RemoveAnimation(mScrollOvershootAnimation);
1401   if(mAnimateOvershootOff)
1402   {
1403     AnimateScrollOvershoot(0.0f);
1404   }
1405 }
1406
1407 void ItemView::ScrollToItem(unsigned int itemId, float durationSeconds)
1408 {
1409   Actor self = Self();
1410   const Vector3 layoutSize = Self().GetCurrentSize();
1411   float firstItemScrollPosition = ClampFirstItemPosition(mActiveLayout->GetItemScrollToPosition(itemId), layoutSize, *mActiveLayout);
1412
1413   if(durationSeconds > 0.0f)
1414   {
1415     RemoveAnimation(mScrollAnimation);
1416     mScrollAnimation = Animation::New(durationSeconds);
1417     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1418     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1419     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1420     mScrollAnimation.Play();
1421   }
1422   else
1423   {
1424     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1425     AnimateScrollOvershoot(0.0f);
1426   }
1427
1428   mScrollStartedSignal.Emit(GetCurrentScrollPosition());
1429   mRefreshEnabled = true;
1430 }
1431
1432 void ItemView::RemoveAnimation(Animation& animation)
1433 {
1434   if(animation)
1435   {
1436     // Cease animating, and reset handle.
1437     animation.Clear();
1438     animation.Reset();
1439   }
1440 }
1441
1442 void ItemView::CalculateDomainSize(const Vector3& layoutSize)
1443 {
1444   Actor self = Self();
1445
1446   Vector3 firstItemPosition(Vector3::ZERO);
1447   Vector3 lastItemPosition(Vector3::ZERO);
1448
1449   if(mActiveLayout)
1450   {
1451     firstItemPosition = mActiveLayout->GetItemPosition( 0,0,layoutSize );
1452
1453     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), layoutSize);
1454     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1455     lastItemPosition = mActiveLayout->GetItemPosition( fabs(minLayoutPosition),fabs(minLayoutPosition),layoutSize );
1456
1457     float domainSize;
1458
1459     if(IsHorizontal(mActiveLayout->GetOrientation()))
1460     {
1461       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.x, 0.0f));
1462       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.x, 0.0f));
1463       domainSize = fabs(firstItemPosition.x - lastItemPosition.x);
1464     }
1465     else
1466     {
1467       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.y, 0.0f));
1468       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.y, 0.0f));
1469       domainSize = fabs(firstItemPosition.y - lastItemPosition.y);
1470     }
1471
1472     mScrollConnector.SetScrollDomain(minLayoutPosition, 0.0f, domainSize);
1473
1474     bool isLayoutScrollable = IsLayoutScrollable(layoutSize);
1475     self.SetProperty(mPropertyCanScrollVertical, isLayoutScrollable);
1476     self.SetProperty(mPropertyCanScrollHorizontal, false);
1477   }
1478 }
1479
1480 Vector3 ItemView::GetDomainSize() const
1481 {
1482   Actor self = Self();
1483
1484   float minScrollPosition = self.GetProperty<float>(mPropertyPositionMin);
1485   float maxScrollPosition = self.GetProperty<float>(mPropertyPositionMax);
1486
1487   return Vector3(0.0f, fabs(maxScrollPosition - minScrollPosition), 0.0f);
1488 }
1489
1490 bool ItemView::IsLayoutScrollable(const Vector3& layoutSize)
1491 {
1492   Actor self = Self();
1493
1494   float currentLayoutPosition = ClampFirstItemPosition( GetCurrentLayoutPosition(0), layoutSize, *mActiveLayout );
1495   float forwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition + 1.0, layoutSize, *mActiveLayout);
1496   float backwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition - 1.0, layoutSize, *mActiveLayout);
1497
1498   return (fabs(forwardClampedPosition - backwardClampedPosition) > Math::MACHINE_EPSILON_0);
1499 }
1500
1501 float ItemView::GetScrollPosition(float layoutPosition, const Vector3& layoutSize) const
1502 {
1503   Vector3 firstItemPosition( mActiveLayout->GetItemPosition(0, layoutPosition, layoutSize ) );
1504   return IsHorizontal(mActiveLayout->GetOrientation()) ? firstItemPosition.x: firstItemPosition.y;
1505 }
1506
1507 Vector3 ItemView::GetCurrentScrollPosition() const
1508 {
1509   float currentLayoutPosition = GetCurrentLayoutPosition(0);
1510   return Vector3(0.0f, GetScrollPosition(currentLayoutPosition, Self().GetCurrentSize()), 0.0f);
1511 }
1512
1513 void ItemView::AddOverlay(Actor actor)
1514 {
1515   Self().Add(actor);
1516 }
1517
1518 void ItemView::RemoveOverlay(Actor actor)
1519 {
1520   Self().Remove(actor);
1521 }
1522
1523 void ItemView::ScrollTo(const Vector3& position, float duration)
1524 {
1525   Actor self = Self();
1526   const Vector3 layoutSize = Self().GetCurrentSize();
1527
1528   float firstItemScrollPosition = ClampFirstItemPosition(position.y, layoutSize, *mActiveLayout);
1529
1530   if(duration > 0.0f)
1531   {
1532     RemoveAnimation(mScrollAnimation);
1533     mScrollAnimation = Animation::New(duration);
1534     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1535     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1536     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1537     mScrollAnimation.Play();
1538   }
1539   else
1540   {
1541     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1542     AnimateScrollOvershoot(0.0f);
1543   }
1544
1545   mScrollStartedSignal.Emit(GetCurrentScrollPosition());
1546   mRefreshEnabled = true;
1547 }
1548
1549 void ItemView::SetOvershootEffectColor( const Vector4& color )
1550 {
1551   mOvershootEffectColor = color;
1552   if( mOvershootOverlay )
1553   {
1554     mOvershootOverlay.SetColor( color );
1555   }
1556 }
1557
1558 void ItemView::SetOvershootEnabled( bool enable )
1559 {
1560   Actor self = Self();
1561   if( enable )
1562   {
1563     Property::Index effectOvershootPropertyIndex = Property::INVALID_INDEX;
1564
1565     Constraint constraint = Constraint::New<Vector3>( Actor::Property::Size,
1566                                                       ParentSource( mPropertyScrollDirection ),
1567                                                       Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1568                                                       ParentSource( Actor::Property::Size ),
1569                                                       OvershootOverlaySizeConstraint() );
1570     mOvershootOverlay.ApplyConstraint(constraint);
1571     mOvershootOverlay.SetSize(OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.width, OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height);
1572
1573     constraint = Constraint::New<Quaternion>( Actor::Property::Rotation,
1574                                               ParentSource( mPropertyScrollDirection ),
1575                                               Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1576                                               OvershootOverlayRotationConstraint() );
1577     mOvershootOverlay.ApplyConstraint(constraint);
1578
1579     constraint = Constraint::New<Vector3>( Actor::Property::Position,
1580                                            ParentSource( Actor::Property::Size ),
1581                                            ParentSource( mPropertyScrollDirection ),
1582                                            Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1583                                            OvershootOverlayPositionConstraint() );
1584     mOvershootOverlay.ApplyConstraint(constraint);
1585
1586     constraint = Constraint::New<bool>( Actor::Property::Visible,
1587                                         ParentSource( mPropertyCanScrollVertical ),
1588                                         OvershootOverlayVisibilityConstraint() );
1589     mOvershootOverlay.ApplyConstraint(constraint);
1590
1591     constraint = Constraint::New<float>( effectOvershootPropertyIndex,
1592                                          Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1593                                          EqualToConstraint() );
1594     mOvershootOverlay.ApplyConstraint(constraint);
1595   }
1596   else
1597   {
1598     if( mOvershootOverlay )
1599     {
1600       self.Remove(mOvershootOverlay);
1601       mOvershootOverlay.Reset();
1602     }
1603   }
1604 }
1605
1606 float ItemView::CalculateScrollOvershoot()
1607 {
1608   float overshoot = 0.0f;
1609
1610   if(mActiveLayout)
1611   {
1612     // The overshoot must be calculated from the accumulated pan gesture displacement
1613     // since the pan gesture starts.
1614     Actor self = Self();
1615     float scrollDistance = CalculateScrollDistance(mTotalPanDisplacement, *mActiveLayout) * mActiveLayout->GetScrollSpeedFactor();
1616     float positionDelta = GetCurrentLayoutPosition(0) + scrollDistance;
1617     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), Self().GetCurrentSize());
1618     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1619     float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, positionDelta));
1620     overshoot = positionDelta - clamppedPosition;
1621   }
1622
1623   return overshoot > 0.0f ? std::min(overshoot, 1.0f) : std::max(overshoot, -1.0f);
1624 }
1625
1626 void ItemView::AnimateScrollOvershoot(float overshootAmount, bool animateBack)
1627 {
1628   bool animatingOn = fabsf(overshootAmount) > Math::MACHINE_EPSILON_1;
1629
1630   // make sure we animate back if needed
1631   mAnimateOvershootOff = animateBack || (!animatingOn && mAnimatingOvershootOn);
1632
1633   if( mAnimatingOvershootOn )
1634   {
1635     // animating on, do not allow animate off
1636     return;
1637   }
1638
1639   if(mOvershootAnimationSpeed > Math::MACHINE_EPSILON_0)
1640   {
1641     float currentOvershoot = mScrollPositionObject.GetProperty<float>(ScrollConnector::OVERSHOOT);
1642     float duration = mOvershootOverlay.GetCurrentSize().height * (animatingOn ? (1.0f - fabsf(currentOvershoot)) : fabsf(currentOvershoot)) / mOvershootAnimationSpeed;
1643
1644     RemoveAnimation(mScrollOvershootAnimation);
1645     mScrollOvershootAnimation = Animation::New(duration);
1646     mScrollOvershootAnimation.FinishedSignal().Connect(this, &ItemView::OnOvershootOnFinished);
1647     mScrollOvershootAnimation.AnimateTo( Property(mScrollPositionObject, ScrollConnector::OVERSHOOT), overshootAmount, TimePeriod(0.0f, duration) );
1648     mScrollOvershootAnimation.Play();
1649
1650     mAnimatingOvershootOn = animatingOn;
1651   }
1652   else
1653   {
1654     mScrollPositionObject.SetProperty( ScrollConnector::OVERSHOOT, overshootAmount );
1655   }
1656 }
1657
1658 void ItemView::SetItemsParentOrigin( const Vector3& parentOrigin )
1659 {
1660   if( parentOrigin != mItemsParentOrigin )
1661   {
1662     mItemsParentOrigin = parentOrigin;
1663     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1664     {
1665       iter->second.SetParentOrigin(parentOrigin);
1666     }
1667   }
1668 }
1669
1670 Vector3 ItemView::GetItemsParentOrigin() const
1671 {
1672   return mItemsParentOrigin;
1673 }
1674
1675 void ItemView::SetItemsAnchorPoint( const Vector3& anchorPoint )
1676 {
1677   if( anchorPoint != mItemsAnchorPoint )
1678   {
1679     mItemsAnchorPoint = anchorPoint;
1680     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1681     {
1682       iter->second.SetAnchorPoint(anchorPoint);
1683     }
1684   }
1685 }
1686
1687 Vector3 ItemView::GetItemsAnchorPoint() const
1688 {
1689   return mItemsAnchorPoint;
1690 }
1691
1692 void ItemView::GetItemsRange(ItemRange& range)
1693 {
1694   if( !mItemPool.empty() )
1695   {
1696     range.begin = mItemPool.begin()->first;
1697     range.end = mItemPool.rbegin()->first + 1;
1698   }
1699   else
1700   {
1701     range.begin = 0;
1702     range.end = 0;
1703   }
1704 }
1705
1706 void ItemView::OnScrollPositionChanged( float position )
1707 {
1708   // Cancel scroll animation to prevent any fighting of setting the scroll position property.
1709   RemoveAnimation(mScrollAnimation);
1710
1711   // Refresh the cache immediately when the scroll position is changed.
1712   DoRefresh(position, false); // No need to cache extra items.
1713 }
1714
1715 } // namespace Internal
1716
1717 } // namespace Toolkit
1718
1719 } // namespace Dali