base/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/constraints.h>
  24 #include <dali/public-api/common/set-wrapper.h>
  25 #include <dali/public-api/common/stage.h>
  26 #include <dali/public-api/events/mouse-wheel-event.h>
  27 #include <dali/public-api/events/touch-event.h>
  28 #include <dali/public-api/object/type-registry.h>
  29
  30 // INTERNAL INCLUDES
  31 #include <dali-toolkit/public-api/controls/scrollable/item-view/item-factory.h>
  32 #include <dali-toolkit/internal/controls/scrollable/scroll-connector-impl.h>
  33 #include <dali-toolkit/internal/controls/scrollable/bouncing-effect-actor.h>
  34
  35 using std::string;
  36 using std::set;
  37 using namespace Dali;
  38
  39 namespace // unnamed namespace
  40 {
  41
  42 //Type registration
  43 TypeRegistration mType( typeid(Toolkit::ItemView), typeid(Toolkit::Scrollable), NULL );
  44
  45 const float DEFAULT_MINIMUM_SWIPE_SPEED = 1.0f;
  46 const float DEFAULT_MINIMUM_SWIPE_DISTANCE = 3.0f;
  47 const float DEFAULT_MOUSE_WHEEL_SCROLL_DISTANCE_STEP_PROPORTION = 0.1f;
  48
  49 const float DEFAULT_MINIMUM_SWIPE_DURATION = 0.45f;
  50 const float DEFAULT_MAXIMUM_SWIPE_DURATION = 2.6f;
  51
  52 const float DEFAULT_REFRESH_INTERVAL_LAYOUT_POSITIONS = 20.0f; // 1 updates per 20 items
  53 const int MOUSE_WHEEL_EVENT_FINISHED_TIME_OUT = 500;  // 0.5 second
  54
  55 const float DEFAULT_ANCHORING_DURATION = 1.0f;  // 1 second
  56
  57 const float MILLISECONDS_PER_SECONDS = 1000.0f;
  58
  59 const Vector2 OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE( 720.0f, 42.0f );
  60 const float OVERSHOOT_BOUNCE_ACTOR_RESIZE_THRESHOLD = 180.0f;
  61 const Vector4 OVERSHOOT_OVERLAY_NINE_PATCH_BORDER(0.0f, 0.0f, 1.0f, 12.0f);
  62 const float MAXIMUM_OVERSHOOT_HEIGHT = 36.0f;  // 36 pixels
  63 const float DEFAULT_OVERSHOOT_ANIMATION_DURATION = 0.5f;  // 0.5 second
  64 const float DEFAULT_KEYBOARD_FOCUS_SCROLL_DURATION = 0.2f;
  65
  66 const string LAYOUT_POSITION_PROPERTY_NAME( "item-view-layout-position" );
  67 const string POSITION_PROPERTY_NAME( "item-view-position" );
  68 const string MINIMUM_LAYOUT_POSITION_PROPERTY_NAME( "item-view-minimum-layout-position" );
  69 const string SCROLL_SPEED_PROPERTY_NAME( "item-view-scroll-speed" );
  70 const string SCROLL_DIRECTION_PROPERTY_NAME( "item-view-scroll-direction" );
  71 const string OVERSHOOT_PROPERTY_NAME( "item-view-overshoot" );
  72
  73 /**
  74  * Local helper to convert pan distance (in actor coordinates) to the layout-specific scrolling direction
  75  */
  76 float CalculateScrollDistance(Vector2 panDistance, Toolkit::ItemLayout& layout)
  77 {
  78   Radian scrollDirection(layout.GetScrollDirection());
  79
  80   float cosTheta = cosf(scrollDirection);
  81   float sinTheta = sinf(scrollDirection);
  82
  83   return panDistance.x * sinTheta + panDistance.y * cosTheta;
  84 }
  85
  86 // Overshoot overlay constraints
  87
  88 struct OvershootOverlaySizeConstraint
  89 {
  90   Vector3 operator()(const Vector3& current,
  91                      const PropertyInput& parentScrollDirectionProperty,
  92                      const PropertyInput& parentOvershootProperty,
  93                      const PropertyInput& parentSizeProperty)
  94   {
  95     const Vector3 parentScrollDirection = parentScrollDirectionProperty.GetVector3();
  96     const Vector3 parentSize = parentSizeProperty.GetVector3();
  97     const Toolkit::ControlOrientation::Type& parentOrientation = static_cast<Toolkit::ControlOrientation::Type>(parentScrollDirection.z);
  98
  99     float overlayWidth;
 100
 101     if(Toolkit::IsVertical(parentOrientation))
 102     {
 103       overlayWidth = fabsf(parentScrollDirection.y) > Math::MACHINE_EPSILON_1 ? parentSize.x : parentSize.y;
 104     }
 105     else
 106     {
 107       overlayWidth = fabsf(parentScrollDirection.x) > Math::MACHINE_EPSILON_1 ? parentSize.y : parentSize.x;
 108     }
 109
 110     float overlayHeight = (overlayWidth > OVERSHOOT_BOUNCE_ACTOR_RESIZE_THRESHOLD) ? OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height : OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height*0.5f;
 111
 112     return Vector3( overlayWidth, overlayHeight, current.depth );
 113   }
 114 };
 115
 116 struct OvershootOverlayRotationConstraint
 117 {
 118   Quaternion operator()(const Quaternion& current,
 119                         const PropertyInput& parentScrollDirectionProperty,
 120                         const PropertyInput& parentOvershootProperty)
 121   {
 122     const Vector3 parentScrollDirection = parentScrollDirectionProperty.GetVector3();
 123     const float parentOvershoot = parentOvershootProperty.GetFloat();
 124     const Toolkit::ControlOrientation::Type& parentOrientation = static_cast<Toolkit::ControlOrientation::Type>(parentScrollDirection.z);
 125
 126     Quaternion rotation;
 127
 128     if(Toolkit::IsVertical(parentOrientation))
 129     {
 130       if(fabsf(parentScrollDirection.y) <= Math::MACHINE_EPSILON_1)
 131       {
 132         if( (parentOrientation == Toolkit::ControlOrientation::Up && parentOvershoot < Math::MACHINE_EPSILON_0)
 133             || (parentOrientation == Toolkit::ControlOrientation::Down && parentOvershoot > Math::MACHINE_EPSILON_0) )
 134         {
 135           rotation = Quaternion(0.5f * Math::PI, Vector3::ZAXIS);
 136         }
 137         else
 138         {
 139           rotation = Quaternion(1.5f * Math::PI, Vector3::ZAXIS);
 140         }
 141       }
 142       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.y > Math::MACHINE_EPSILON_0)
 143             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.y < Math::MACHINE_EPSILON_0) )
 144       {
 145         rotation = Quaternion(0.0f, Vector3::ZAXIS);
 146       }
 147       else
 148       {
 149         rotation = Quaternion(Math::PI, Vector3::ZAXIS);
 150       }
 151     }
 152     else
 153     {
 154       if(fabsf(parentScrollDirection.x) <= Math::MACHINE_EPSILON_1)
 155       {
 156         if( (parentOrientation == Toolkit::ControlOrientation::Left && parentOvershoot > Math::MACHINE_EPSILON_0)
 157             ||(parentOrientation == Toolkit::ControlOrientation::Right && parentOvershoot < Math::MACHINE_EPSILON_0) )
 158         {
 159           rotation = Quaternion(Math::PI, Vector3::ZAXIS);
 160         }
 161         else
 162         {
 163           rotation = Quaternion(0.0f, Vector3::ZAXIS);
 164         }
 165       }
 166       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.x > Math::MACHINE_EPSILON_0)
 167             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.x < Math::MACHINE_EPSILON_0) )
 168       {
 169         rotation = Quaternion(1.5f * Math::PI, Vector3::ZAXIS);
 170       }
 171       else
 172       {
 173         rotation = Quaternion(0.5f * Math::PI, Vector3::ZAXIS);
 174       }
 175     }
 176
 177     return rotation;
 178   }
 179 };
 180
 181 struct OvershootOverlayPositionConstraint
 182 {
 183   Vector3 operator()(const Vector3&    current,
 184                      const PropertyInput& parentSizeProperty,
 185                      const PropertyInput& parentScrollDirectionProperty,
 186                      const PropertyInput& parentOvershootProperty)
 187   {
 188     const Vector3 parentScrollDirection = parentScrollDirectionProperty.GetVector3();
 189     const float parentOvershoot = parentOvershootProperty.GetFloat();
 190     const Vector3 parentSize = parentSizeProperty.GetVector3();
 191     const Toolkit::ControlOrientation::Type& parentOrientation = static_cast<Toolkit::ControlOrientation::Type>(parentScrollDirection.z);
 192
 193     Vector3 relativeOffset;
 194
 195     if(Toolkit::IsVertical(parentOrientation))
 196     {
 197       if(fabsf(parentScrollDirection.y) <= Math::MACHINE_EPSILON_1)
 198       {
 199         if( (parentOrientation == Toolkit::ControlOrientation::Up && parentOvershoot < Math::MACHINE_EPSILON_0)
 200             || (parentOrientation == Toolkit::ControlOrientation::Down && parentOvershoot > Math::MACHINE_EPSILON_0) )
 201         {
 202           relativeOffset = Vector3(1.0f, 0.0f, 0.0f);
 203         }
 204         else
 205         {
 206           relativeOffset =Vector3(0.0f, 1.0f, 0.0f);
 207         }
 208       }
 209       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.y > Math::MACHINE_EPSILON_0)
 210             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.y < Math::MACHINE_EPSILON_0) )
 211       {
 212         relativeOffset = Vector3(0.0f, 0.0f, 0.0f);
 213       }
 214       else
 215       {
 216         relativeOffset = Vector3(1.0f, 1.0f, 0.0f);
 217       }
 218     }
 219     else
 220     {
 221       if(fabsf(parentScrollDirection.x) <= Math::MACHINE_EPSILON_1)
 222       {
 223         if( (parentOrientation == Toolkit::ControlOrientation::Left && parentOvershoot < Math::MACHINE_EPSILON_0)
 224             || (parentOrientation == Toolkit::ControlOrientation::Right && parentOvershoot > Math::MACHINE_EPSILON_0) )
 225         {
 226           relativeOffset = Vector3(0.0f, 0.0f, 0.0f);
 227         }
 228         else
 229         {
 230           relativeOffset = Vector3(1.0f, 1.0f, 0.0f);
 231         }
 232       }
 233       else if( (parentOvershoot > Math::MACHINE_EPSILON_0 && parentScrollDirection.x > Math::MACHINE_EPSILON_0)
 234             || (parentOvershoot < Math::MACHINE_EPSILON_0 && parentScrollDirection.x < Math::MACHINE_EPSILON_0) )
 235       {
 236         relativeOffset = Vector3(0.0f, 1.0f, 0.0f);
 237       }
 238       else
 239       {
 240         relativeOffset = Vector3(1.0f, 0.0f, 0.0f);
 241       }
 242     }
 243
 244     return relativeOffset * parentSize;
 245
 246   }
 247 };
 248
 249 struct OvershootOverlayVisibilityConstraint
 250 {
 251   bool operator()(const bool& current,
 252                   const PropertyInput& parentLayoutScrollableProperty)
 253   {
 254     const bool parentLayoutScrollable = parentLayoutScrollableProperty.GetBoolean();
 255
 256     return parentLayoutScrollable;
 257   }
 258 };
 259
 260 /**
 261  * Relative position Constraint
 262  * Generates the relative position value of the item view based on the layout position,
 263  * and it's relation to the layout domain. This is a value from 0.0f to 1.0f in each axis.
 264  */
 265 Vector3 RelativePositionConstraint(const Vector3& current,
 266                                    const PropertyInput& scrollPositionProperty,
 267                                    const PropertyInput& scrollMinProperty,
 268                                    const PropertyInput& scrollMaxProperty,
 269                                    const PropertyInput& layoutSizeProperty)
 270 {
 271   const Vector3& position = Vector3(0.0f, scrollPositionProperty.GetFloat(), 0.0f);
 272   const Vector3& min = scrollMinProperty.GetVector3();
 273   const Vector3& max = scrollMaxProperty.GetVector3();
 274
 275   Vector3 relativePosition;
 276   Vector3 domainSize = max - min;
 277
 278   relativePosition.x = fabsf(domainSize.x) > Math::MACHINE_EPSILON_1 ? ((min.x - position.x) / fabsf(domainSize.x)) : 0.0f;
 279   relativePosition.y = fabsf(domainSize.y) > Math::MACHINE_EPSILON_1 ? ((min.y - position.y) / fabsf(domainSize.y)) : 0.0f;
 280
 281   return relativePosition;
 282 }
 283
 284 } // unnamed namespace
 285
 286 namespace Dali
 287 {
 288
 289 namespace Toolkit
 290 {
 291
 292 namespace Internal
 293 {
 294
 295 namespace // unnamed namespace
 296 {
 297
 298 bool FindById( const ItemContainer& items, ItemId id )
 299 {
 300   for( ConstItemIter iter = items.begin(); items.end() != iter; ++iter )
 301   {
 302     if( iter->first == id )
 303     {
 304       return true;
 305     }
 306   }
 307
 308   return false;
 309 }
 310
 311 } // unnamed namespace
 312
 313 Dali::Toolkit::ItemView ItemView::New(ItemFactory& factory)
 314 {
 315   // Create the implementation
 316   ItemViewPtr itemView(new ItemView(factory));
 317
 318   // Pass ownership to CustomActor via derived handle
 319   Dali::Toolkit::ItemView handle(*itemView);
 320
 321   // Second-phase init of the implementation
 322   // This can only be done after the CustomActor connection has been made...
 323   itemView->Initialize();
 324
 325   return handle;
 326 }
 327
 328 ItemView::ItemView(ItemFactory& factory)
 329 : Scrollable(),
 330   mItemFactory(factory),
 331   mActiveLayout(NULL),
 332   mAnimatingOvershootOn(false),
 333   mAnimateOvershootOff(false),
 334   mAnchoringEnabled(true),
 335   mAnchoringDuration(DEFAULT_ANCHORING_DURATION),
 336   mRefreshIntervalLayoutPositions(0.0f),
 337   mRefreshOrderHint(true/*Refresh item 0 first*/),
 338   mMinimumSwipeSpeed(DEFAULT_MINIMUM_SWIPE_SPEED),
 339   mMinimumSwipeDistance(DEFAULT_MINIMUM_SWIPE_DISTANCE),
 340   mMouseWheelScrollDistanceStep(0.0f),
 341   mScrollDistance(0.0f),
 342   mScrollSpeed(0.0f),
 343   mTotalPanDisplacement(Vector2::ZERO),
 344   mScrollOvershoot(0.0f),
 345   mIsFlicking(false),
 346   mGestureState(Gesture::Clear),
 347   mAddingItems(false),
 348   mPropertyPosition(Property::INVALID_INDEX),
 349   mPropertyMinimumLayoutPosition(Property::INVALID_INDEX),
 350   mPropertyScrollSpeed(Property::INVALID_INDEX),
 351   mRefreshEnabled(true),
 352   mItemsParentOrigin( ParentOrigin::CENTER),
 353   mItemsAnchorPoint( AnchorPoint::CENTER)
 354 {
 355   SetRequiresMouseWheelEvents(true);
 356   SetKeyboardNavigationSupport(true);
 357 }
 358
 359 void ItemView::OnInitialize()
 360 {
 361   SetSizePolicy( Toolkit::Control::Fixed, Toolkit::Control::Fixed );
 362
 363   RegisterCommonProperties();
 364
 365   Actor self = Self();
 366
 367   mScrollConnector = Dali::Toolkit::ScrollConnector::New();
 368   mScrollPositionObject = mScrollConnector.GetScrollPositionObject();
 369   mScrollConnector.ScrollPositionChangedSignal().Connect( this, &ItemView::OnScrollPositionChanged );
 370
 371   mPropertyMinimumLayoutPosition = self.RegisterProperty(MINIMUM_LAYOUT_POSITION_PROPERTY_NAME, 0.0f);
 372   mPropertyPosition = self.RegisterProperty(POSITION_PROPERTY_NAME, 0.0f);
 373   mPropertyScrollSpeed = self.RegisterProperty(SCROLL_SPEED_PROPERTY_NAME, 0.0f);
 374
 375   EnableScrollComponent(Toolkit::Scrollable::OvershootIndicator);
 376
 377   Constraint constraint = Constraint::New<Vector3>(mPropertyRelativePosition,
 378                                                    LocalSource(mPropertyPosition),
 379                                                    LocalSource(mPropertyPositionMin),
 380                                                    LocalSource(mPropertyPositionMax),
 381                                                    LocalSource(Actor::SIZE),
 382                                                    RelativePositionConstraint);
 383   self.ApplyConstraint(constraint);
 384
 385   Vector2 stageSize = Stage::GetCurrent().GetSize();
 386   mMouseWheelScrollDistanceStep = stageSize.y * DEFAULT_MOUSE_WHEEL_SCROLL_DISTANCE_STEP_PROPORTION;
 387
 388   EnableGestureDetection(Gesture::Type(Gesture::Pan));
 389
 390   mMouseWheelEventFinishedTimer = Timer::New( MOUSE_WHEEL_EVENT_FINISHED_TIME_OUT );
 391   mMouseWheelEventFinishedTimer.TickSignal().Connect( this, &ItemView::OnMouseWheelEventFinished );
 392
 393   SetRefreshInterval(DEFAULT_REFRESH_INTERVAL_LAYOUT_POSITIONS);
 394 }
 395
 396 ItemView::~ItemView()
 397 {
 398 }
 399
 400 Dali::Toolkit::ScrollConnector ItemView::GetScrollConnector() const
 401 {
 402   return mScrollConnector;
 403 }
 404
 405 unsigned int ItemView::GetLayoutCount() const
 406 {
 407   return mLayouts.size();
 408 }
 409
 410 void ItemView::AddLayout(ItemLayout& layout)
 411 {
 412   mLayouts.push_back(ItemLayoutPtr(&layout));
 413 }
 414
 415 void ItemView::RemoveLayout(unsigned int layoutIndex)
 416 {
 417   DALI_ASSERT_ALWAYS(layoutIndex < mLayouts.size());
 418
 419   if (mActiveLayout == mLayouts[layoutIndex].Get())
 420   {
 421     mActiveLayout = NULL;
 422   }
 423
 424   mLayouts.erase(mLayouts.begin() + layoutIndex);
 425 }
 426
 427 ItemLayoutPtr ItemView::GetLayout(unsigned int layoutIndex) const
 428 {
 429   return mLayouts[layoutIndex];
 430 }
 431
 432 ItemLayoutPtr ItemView::GetActiveLayout() const
 433 {
 434   return ItemLayoutPtr(mActiveLayout);
 435 }
 436
 437 float ItemView::GetCurrentLayoutPosition(unsigned int itemId) const
 438 {
 439   return mScrollConnector.GetScrollPosition() + static_cast<float>( itemId );
 440 }
 441
 442 void ItemView::ActivateLayout(unsigned int layoutIndex, const Vector3& targetSize, float durationSeconds)
 443 {
 444   DALI_ASSERT_ALWAYS(layoutIndex < mLayouts.size());
 445
 446   mRefreshEnabled = false;
 447
 448   Actor self = Self();
 449
 450   // The ItemView size should match the active layout size
 451   self.SetSize(targetSize);
 452   mActiveLayoutTargetSize = targetSize;
 453
 454   // Switch to the new layout
 455   mActiveLayout = mLayouts[layoutIndex].Get();
 456
 457   // Move the items to the new layout positions...
 458
 459   bool resizeAnimationNeeded(false);
 460   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 461   {
 462     unsigned int itemId = iter->first;
 463     Actor actor = iter->second;
 464
 465     // Remove constraints from previous layout
 466     actor.RemoveConstraints();
 467
 468     Vector3 size;
 469     if(mActiveLayout->GetItemSize(itemId, targetSize, size))
 470     {
 471       if( durationSeconds > 0.0f )
 472       {
 473         // Use a size animation
 474         if (!resizeAnimationNeeded)
 475         {
 476           resizeAnimationNeeded = true;
 477           RemoveAnimation(mResizeAnimation);
 478           mResizeAnimation = Animation::New(durationSeconds);
 479         }
 480
 481         // The layout provides its own resize animation
 482         mActiveLayout->GetResizeAnimation(mResizeAnimation, actor, size, durationSeconds);
 483       }
 484       else
 485       {
 486         // resize immediately
 487         actor.SetSize(size);
 488       }
 489     }
 490
 491     mActiveLayout->ApplyConstraints(actor, itemId, durationSeconds, mScrollPositionObject, Self() );
 492   }
 493
 494   if (resizeAnimationNeeded)
 495   {
 496     mResizeAnimation.Play();
 497   }
 498
 499   // Refresh the new layout
 500   ItemRange range = GetItemRange(*mActiveLayout, targetSize, GetCurrentLayoutPosition(0), false/* don't reserve extra*/);
 501   AddActorsWithinRange( range, durationSeconds );
 502
 503   // Scroll to an appropriate layout position
 504
 505   bool scrollAnimationNeeded(false);
 506   float firstItemScrollPosition(0.0f);
 507
 508   float current = GetCurrentLayoutPosition(0);
 509   float minimum = ClampFirstItemPosition(current, targetSize, *mActiveLayout);
 510   self.SetProperty(mPropertyPosition, GetScrollPosition(current, targetSize));
 511
 512   if (current < minimum)
 513   {
 514     scrollAnimationNeeded = true;
 515     firstItemScrollPosition = minimum;
 516   }
 517   else if (mAnchoringEnabled)
 518   {
 519     scrollAnimationNeeded = true;
 520     firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(current);
 521   }
 522
 523   if (scrollAnimationNeeded)
 524   {
 525     RemoveAnimation(mScrollAnimation);
 526     mScrollAnimation = Animation::New(durationSeconds);
 527     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
 528     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, targetSize), AlphaFunctions::EaseOut );
 529     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnLayoutActivationScrollFinished);
 530     mScrollAnimation.Play();
 531   }
 532
 533   self.SetProperty(mPropertyMinimumLayoutPosition, mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize));
 534   AnimateScrollOvershoot(0.0f);
 535   mScrollOvershoot = 0.0f;
 536
 537   Radian scrollDirection(mActiveLayout->GetScrollDirection());
 538   float orientation = static_cast<float>(mActiveLayout->GetOrientation());
 539   self.SetProperty(mPropertyScrollDirection, Vector3(sinf(scrollDirection), cosf(scrollDirection), orientation));
 540
 541   self.SetProperty(mPropertyScrollSpeed, mScrollSpeed);
 542
 543   CalculateDomainSize(targetSize);
 544 }
 545
 546 void ItemView::DeactivateCurrentLayout()
 547 {
 548   if (mActiveLayout)
 549   {
 550     for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 551     {
 552       Actor actor = iter->second;
 553       actor.RemoveConstraints();
 554     }
 555
 556     mActiveLayout = NULL;
 557   }
 558 }
 559
 560 void ItemView::OnRefreshNotification(PropertyNotification& source)
 561 {
 562   if(mRefreshEnabled || mScrollAnimation)
 563   {
 564     // Only refresh the cache during normal scrolling
 565     DoRefresh(GetCurrentLayoutPosition(0), true);
 566   }
 567 }
 568
 569 void ItemView::DoRefresh(float currentLayoutPosition, bool cacheExtra)
 570 {
 571   if (mActiveLayout)
 572   {
 573     ItemRange range = GetItemRange(*mActiveLayout, mActiveLayoutTargetSize, currentLayoutPosition, cacheExtra/*reserve extra*/);
 574     RemoveActorsOutsideRange( range );
 575     AddActorsWithinRange( range, 0.0f/*immediate*/ );
 576
 577     mScrollUpdatedSignalV2.Emit( Vector3(0.0f, currentLayoutPosition, 0.0f) );
 578   }
 579 }
 580
 581 void ItemView::SetMinimumSwipeSpeed(float speed)
 582 {
 583   mMinimumSwipeSpeed = speed;
 584 }
 585
 586 float ItemView::GetMinimumSwipeSpeed() const
 587 {
 588   return mMinimumSwipeSpeed;
 589 }
 590
 591 void ItemView::SetMinimumSwipeDistance(float distance)
 592 {
 593   mMinimumSwipeDistance = distance;
 594 }
 595
 596 float ItemView::GetMinimumSwipeDistance() const
 597 {
 598   return mMinimumSwipeDistance;
 599 }
 600
 601 void ItemView::SetMouseWheelScrollDistanceStep(float step)
 602 {
 603   mMouseWheelScrollDistanceStep = step;
 604 }
 605
 606 float ItemView::GetMouseWheelScrollDistanceStep() const
 607 {
 608   return mMouseWheelScrollDistanceStep;
 609 }
 610
 611 void ItemView::SetAnchoring(bool enabled)
 612 {
 613   mAnchoringEnabled = enabled;
 614 }
 615
 616 bool ItemView::GetAnchoring() const
 617 {
 618   return mAnchoringEnabled;
 619 }
 620
 621 void ItemView::SetAnchoringDuration(float durationSeconds)
 622 {
 623   mAnchoringDuration = durationSeconds;
 624 }
 625
 626 float ItemView::GetAnchoringDuration() const
 627 {
 628   return mAnchoringDuration;
 629 }
 630
 631 void ItemView::SetRefreshInterval(float intervalLayoutPositions)
 632 {
 633   if( !Equals(mRefreshIntervalLayoutPositions, intervalLayoutPositions) )
 634   {
 635     mRefreshIntervalLayoutPositions = intervalLayoutPositions;
 636
 637     if(mRefreshNotification)
 638     {
 639       mScrollPositionObject.RemovePropertyNotification(mRefreshNotification);
 640     }
 641     mRefreshNotification = mScrollPositionObject.AddPropertyNotification( ScrollConnector::SCROLL_POSITION, StepCondition(mRefreshIntervalLayoutPositions, 0.0f) );
 642     mRefreshNotification.NotifySignal().Connect( this, &ItemView::OnRefreshNotification );
 643   }
 644 }
 645
 646 float ItemView::GetRefreshInterval() const
 647 {
 648   return mRefreshIntervalLayoutPositions;
 649 }
 650
 651 void ItemView::SetRefreshEnabled(bool enabled)
 652 {
 653   mRefreshEnabled = enabled;
 654 }
 655
 656 Actor ItemView::GetItem(unsigned int itemId) const
 657 {
 658   Actor actor;
 659
 660   ConstItemPoolIter iter = mItemPool.find( itemId );
 661   if( iter != mItemPool.end() )
 662   {
 663     actor = iter->second;
 664   }
 665
 666   return actor;
 667 }
 668
 669 unsigned int ItemView::GetItemId( Actor actor ) const
 670 {
 671   unsigned int itemId( 0 );
 672
 673   for ( ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter )
 674   {
 675     if( iter->second == actor )
 676     {
 677       itemId = iter->first;
 678       break;
 679     }
 680   }
 681
 682   return itemId;
 683 }
 684
 685 void ItemView::InsertItem( Item newItem, float durationSeconds )
 686 {
 687   mAddingItems = true;
 688
 689   Actor displacedActor;
 690   ItemPoolIter afterDisplacedIter = mItemPool.end();
 691
 692   ItemPoolIter foundIter = mItemPool.find( newItem.first );
 693   if( mItemPool.end() != foundIter )
 694   {
 695     SetupActor( newItem, durationSeconds );
 696     Self().Add( newItem.second );
 697
 698     displacedActor = foundIter->second;
 699     foundIter->second = newItem.second;
 700
 701     afterDisplacedIter = ++foundIter;
 702   }
 703   else
 704   {
 705     // Inserting before the existing item range?
 706     ItemPoolIter iter = mItemPool.begin();
 707     if( iter != mItemPool.end() &&
 708         iter->first > newItem.first )
 709     {
 710       displacedActor = iter->second;
 711       mItemPool.erase( iter++ ); // iter is still valid after the erase
 712
 713       afterDisplacedIter = iter;
 714     }
 715   }
 716
 717   if( displacedActor )
 718   {
 719     // Move the existing actors to make room
 720     for( ItemPoolIter iter = afterDisplacedIter; mItemPool.end() != iter; ++iter )
 721     {
 722       Actor temp = iter->second;
 723       iter->second = displacedActor;
 724       displacedActor = temp;
 725
 726       iter->second.RemoveConstraints();
 727       mActiveLayout->ApplyConstraints(iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 728     }
 729
 730     // Create last item
 731     ItemId lastId = mItemPool.rbegin()->first;
 732     Item lastItem( lastId + 1, displacedActor );
 733     mItemPool.insert( lastItem );
 734
 735     lastItem.second.RemoveConstraints();
 736     mActiveLayout->ApplyConstraints(lastItem.second, lastItem.first, durationSeconds, mScrollPositionObject, Self() );
 737   }
 738
 739   CalculateDomainSize(Self().GetCurrentSize());
 740
 741   mAddingItems = false;
 742 }
 743
 744 void ItemView::InsertItems( const ItemContainer& newItems, float durationSeconds )
 745 {
 746   mAddingItems = true;
 747
 748   // Insert from lowest id to highest
 749   std::set<Item> sortedItems;
 750   for( ConstItemIter iter = newItems.begin(); newItems.end() != iter; ++iter )
 751   {
 752     sortedItems.insert( *iter );
 753   }
 754
 755   for( std::set<Item>::iterator iter = sortedItems.begin(); sortedItems.end() != iter; ++iter )
 756   {
 757     Self().Add( iter->second );
 758
 759     ItemPoolIter foundIter = mItemPool.find( iter->first );
 760     if( mItemPool.end() != foundIter )
 761     {
 762       Actor moveMe = foundIter->second;
 763       foundIter->second = iter->second;
 764
 765       // Move the existing actors to make room
 766       for( ItemPoolIter iter = ++foundIter; mItemPool.end() != iter; ++iter )
 767       {
 768         Actor temp = iter->second;
 769         iter->second = moveMe;
 770         moveMe = temp;
 771       }
 772
 773       // Create last item
 774       ItemId lastId = mItemPool.rbegin()->first;
 775       Item lastItem( lastId + 1, moveMe );
 776       mItemPool.insert( lastItem );
 777     }
 778     else
 779     {
 780       mItemPool.insert( *iter );
 781     }
 782   }
 783
 784   // Relayout everything
 785   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 786   {
 787     // If newly inserted
 788     if( FindById( newItems, iter->first ) )
 789     {
 790       SetupActor( *iter, durationSeconds );
 791     }
 792     else
 793     {
 794       iter->second.RemoveConstraints();
 795       mActiveLayout->ApplyConstraints( iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 796     }
 797   }
 798
 799   CalculateDomainSize(Self().GetCurrentSize());
 800
 801   mAddingItems = false;
 802 }
 803
 804 void ItemView::RemoveItem( unsigned int itemId, float durationSeconds )
 805 {
 806   bool actorsReordered = RemoveActor( itemId );
 807   if( actorsReordered )
 808   {
 809     ReapplyAllConstraints( durationSeconds );
 810
 811     OnItemsRemoved();
 812   }
 813 }
 814
 815 void ItemView::RemoveItems( const ItemIdContainer& itemIds, float durationSeconds )
 816 {
 817   bool actorsReordered( false );
 818
 819   // Remove from highest id to lowest
 820   set<ItemId> sortedItems;
 821   for( ConstItemIdIter iter = itemIds.begin(); itemIds.end() != iter; ++iter )
 822   {
 823     sortedItems.insert( *iter );
 824   }
 825
 826   for( set<ItemId>::reverse_iterator iter = sortedItems.rbegin(); sortedItems.rend() != iter; ++iter )
 827   {
 828     if( RemoveActor( *iter ) )
 829     {
 830       actorsReordered = true;
 831     }
 832   }
 833
 834   if( actorsReordered )
 835   {
 836     ReapplyAllConstraints( durationSeconds );
 837
 838     OnItemsRemoved();
 839   }
 840 }
 841
 842 bool ItemView::RemoveActor(unsigned int itemId)
 843 {
 844   bool reordered( false );
 845
 846   ItemPoolIter removeIter = mItemPool.find( itemId );
 847   if( removeIter != mItemPool.end() )
 848   {
 849     ReleaseActor(itemId, removeIter->second);
 850   }
 851   else
 852   {
 853     // Removing before the existing item range?
 854     ItemPoolIter iter = mItemPool.begin();
 855     if( iter != mItemPool.end() &&
 856         iter->first > itemId )
 857     {
 858       // In order to decrement the first visible item ID
 859       mItemPool.insert( Item(iter->first - 1, Actor()) );
 860
 861       removeIter = mItemPool.begin();
 862     }
 863   }
 864
 865   if( removeIter != mItemPool.end() )
 866   {
 867     reordered = true;
 868
 869     // Adjust the remaining item IDs, for example if item 2 is removed:
 870     //   Initial actors:     After insert:
 871     //     ID 1 - ActorA       ID 1 - ActorA
 872     //     ID 2 - ActorB       ID 2 - ActorC (previously ID 3)
 873     //     ID 3 - ActorC       ID 3 - ActorB (previously ID 4)
 874     //     ID 4 - ActorD
 875     for (ItemPoolIter iter = removeIter; iter != mItemPool.end(); ++iter)
 876     {
 877       if( iter->first < mItemPool.rbegin()->first )
 878       {
 879         iter->second = mItemPool[ iter->first + 1 ];
 880       }
 881       else
 882       {
 883         mItemPool.erase( iter );
 884         break;
 885       }
 886     }
 887   }
 888
 889   return reordered;
 890 }
 891
 892 void ItemView::ReplaceItem( Item replacementItem, float durationSeconds )
 893 {
 894   mAddingItems = true;
 895
 896   SetupActor( replacementItem, durationSeconds );
 897   Self().Add( replacementItem.second );
 898
 899   const ItemPoolIter iter = mItemPool.find( replacementItem.first );
 900   if( mItemPool.end() != iter )
 901   {
 902     ReleaseActor(iter->first, iter->second);
 903     iter->second = replacementItem.second;
 904   }
 905   else
 906   {
 907     mItemPool.insert( replacementItem );
 908   }
 909
 910   CalculateDomainSize(Self().GetCurrentSize());
 911
 912   mAddingItems = false;
 913 }
 914
 915 void ItemView::ReplaceItems( const ItemContainer& replacementItems, float durationSeconds )
 916 {
 917   for( ConstItemIter iter = replacementItems.begin(); replacementItems.end() != iter; ++iter )
 918   {
 919     ReplaceItem( *iter, durationSeconds );
 920   }
 921 }
 922
 923 void ItemView::RemoveActorsOutsideRange( ItemRange range )
 924 {
 925   // Remove unwanted actors from the ItemView & ItemPool
 926   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); )
 927   {
 928     unsigned int current = iter->first;
 929
 930     if( ! range.Within( current ) )
 931     {
 932       ReleaseActor(iter->first, iter->second);
 933
 934       mItemPool.erase( iter++ ); // erase invalidates the return value of post-increment; iter remains valid
 935     }
 936     else
 937     {
 938       ++iter;
 939     }
 940   }
 941 }
 942
 943 void ItemView::AddActorsWithinRange( ItemRange range, float durationSeconds )
 944 {
 945   range.end = std::min(mItemFactory.GetNumberOfItems(), range.end);
 946
 947   // The order of addition depends on the scroll direction.
 948   if (mRefreshOrderHint)
 949   {
 950     for (unsigned int itemId = range.begin; itemId < range.end; ++itemId)
 951     {
 952       AddNewActor( itemId, durationSeconds );
 953     }
 954   }
 955   else
 956   {
 957     for (unsigned int itemId = range.end; itemId > range.begin; --itemId)
 958     {
 959       AddNewActor( itemId-1, durationSeconds );
 960     }
 961   }
 962
 963   // Total number of items may change dynamically.
 964   // Always recalculate the domain size to reflect that.
 965   CalculateDomainSize(Self().GetCurrentSize());
 966 }
 967
 968 void ItemView::AddNewActor( unsigned int itemId, float durationSeconds )
 969 {
 970   mAddingItems = true;
 971
 972   if( mItemPool.end() == mItemPool.find( itemId ) )
 973   {
 974     Actor actor = mItemFactory.NewItem( itemId );
 975
 976     if( actor )
 977     {
 978       Item newItem( itemId, actor );
 979
 980       mItemPool.insert( newItem );
 981
 982       SetupActor( newItem, durationSeconds );
 983       Self().Add( actor );
 984     }
 985   }
 986
 987   mAddingItems = false;
 988 }
 989
 990 void ItemView::SetupActor( Item item, float durationSeconds )
 991 {
 992   item.second.SetParentOrigin( mItemsParentOrigin );
 993   item.second.SetAnchorPoint( mItemsAnchorPoint );
 994
 995   if( mActiveLayout )
 996   {
 997     Vector3 size;
 998     if( mActiveLayout->GetItemSize( item.first, mActiveLayoutTargetSize, size ) )
 999     {
1000       item.second.SetSize( size );
1001     }
1002
1003     mActiveLayout->ApplyConstraints( item.second, item.first, durationSeconds, mScrollPositionObject, Self() );
1004   }
1005 }
1006
1007 void ItemView::ReleaseActor( ItemId item, Actor actor )
1008 {
1009   Self().Remove( actor );
1010   mItemFactory.ItemReleased(item, actor);
1011 }
1012
1013 ItemRange ItemView::GetItemRange(ItemLayout& layout, const Vector3& layoutSize, float layoutPosition, bool reserveExtra)
1014 {
1015   unsigned int itemCount = mItemFactory.GetNumberOfItems();
1016
1017   ItemRange available(0u, itemCount);
1018
1019   ItemRange range = layout.GetItemsWithinArea( layoutPosition, layoutSize );
1020
1021   if (reserveExtra)
1022   {
1023     // Add the reserve items for scrolling
1024     unsigned int extra = layout.GetReserveItemCount(layoutSize);
1025     range.begin = (range.begin >= extra) ? (range.begin - extra) : 0u;
1026     range.end += extra;
1027   }
1028
1029   return range.Intersection(available);
1030 }
1031
1032 void ItemView::OnChildAdd(Actor& child)
1033 {
1034   if(!mAddingItems)
1035   {
1036     // We don't want to do this downcast check for any item added by ItemView itself.
1037     Dali::Toolkit::ScrollComponent scrollComponent = Dali::Toolkit::ScrollComponent::DownCast(child);
1038     if(scrollComponent)
1039     {
1040       // Set the scroll connector when scroll bar is being added
1041       scrollComponent.SetScrollConnector(mScrollConnector);
1042     }
1043   }
1044 }
1045
1046 bool ItemView::OnTouchEvent(const TouchEvent& event)
1047 {
1048   // Ignore events with multiple-touch points
1049   if (event.GetPointCount() != 1)
1050   {
1051     return false;
1052   }
1053
1054   if (event.GetPoint(0).state == TouchPoint::Down)
1055   {
1056     // Cancel ongoing scrolling etc.
1057     mGestureState = Gesture::Clear;
1058
1059     mScrollDistance = 0.0f;
1060     mScrollSpeed = 0.0f;
1061     Self().SetProperty(mPropertyScrollSpeed, mScrollSpeed);
1062
1063     mScrollOvershoot = 0.0f;
1064     AnimateScrollOvershoot(0.0f);
1065
1066     if(mScrollAnimation)
1067     {
1068       mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1069     }
1070
1071     RemoveAnimation(mScrollAnimation);
1072   }
1073
1074   return true; // consume since we're potentially scrolling
1075 }
1076
1077 bool ItemView::OnMouseWheelEvent(const MouseWheelEvent& event)
1078 {
1079   // Respond the mouse wheel event to scroll
1080   if (mActiveLayout)
1081   {
1082     Actor self = Self();
1083     const Vector3 layoutSize = Self().GetCurrentSize();
1084     float layoutPositionDelta = GetCurrentLayoutPosition(0) - (event.z * mMouseWheelScrollDistanceStep * mActiveLayout->GetScrollSpeedFactor());
1085     float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1086
1087     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1088     self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1089     mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1090     mRefreshEnabled = true;
1091   }
1092
1093   if (mMouseWheelEventFinishedTimer.IsRunning())
1094   {
1095     mMouseWheelEventFinishedTimer.Stop();
1096   }
1097
1098   mMouseWheelEventFinishedTimer.Start();
1099
1100   return true;
1101 }
1102
1103 bool ItemView::OnMouseWheelEventFinished()
1104 {
1105   if (mActiveLayout)
1106   {
1107     RemoveAnimation(mScrollAnimation);
1108
1109     // No more mouse wheel events coming. Do the anchoring if enabled.
1110     mScrollAnimation = DoAnchoring();
1111     if (mScrollAnimation)
1112     {
1113       mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1114       mScrollAnimation.Play();
1115     }
1116     else
1117     {
1118       mScrollOvershoot = 0.0f;
1119       AnimateScrollOvershoot(0.0f);
1120
1121       mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1122     }
1123   }
1124
1125   return false;
1126 }
1127
1128 void ItemView::ReapplyAllConstraints( float durationSeconds )
1129 {
1130   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1131   {
1132     unsigned int id = iter->first;
1133     Actor actor = iter->second;
1134
1135     actor.RemoveConstraints();
1136     mActiveLayout->ApplyConstraints(actor, id, durationSeconds, mScrollPositionObject, Self());
1137   }
1138 }
1139
1140 void ItemView::OnItemsRemoved()
1141 {
1142   CalculateDomainSize(Self().GetCurrentSize());
1143
1144   // Adjust scroll-position after an item is removed
1145   if( mActiveLayout )
1146   {
1147     float firstItemScrollPosition = ClampFirstItemPosition(GetCurrentLayoutPosition(0), Self().GetCurrentSize(), *mActiveLayout);
1148
1149     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1150   }
1151 }
1152
1153 float ItemView::ClampFirstItemPosition(float targetPosition, const Vector3& targetSize, ItemLayout& layout)
1154 {
1155   Actor self = Self();
1156   float minLayoutPosition = layout.GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize);
1157   float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, targetPosition));
1158   mScrollOvershoot = targetPosition - clamppedPosition;
1159   self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1160
1161   return clamppedPosition;
1162 }
1163
1164 void ItemView::OnPan( const PanGesture& gesture )
1165 {
1166   Actor self = Self();
1167   const Vector3 layoutSize = Self().GetCurrentSize();
1168
1169   RemoveAnimation(mScrollAnimation);
1170
1171   // Short-circuit if there is no active layout
1172   if (!mActiveLayout)
1173   {
1174     mGestureState = Gesture::Clear;
1175     return;
1176   }
1177
1178   mGestureState = gesture.state;
1179
1180   switch (mGestureState)
1181   {
1182     case Gesture::Finished:
1183     {
1184       // Swipe Detection
1185       if (fabsf(mScrollDistance) > mMinimumSwipeDistance &&
1186           mScrollSpeed > mMinimumSwipeSpeed)
1187       {
1188         float direction = (mScrollDistance < 0.0f) ? -1.0f : 1.0f;
1189
1190         mRefreshOrderHint = true;
1191
1192         float currentLayoutPosition = GetCurrentLayoutPosition(0);
1193         float firstItemScrollPosition = ClampFirstItemPosition(currentLayoutPosition + mScrollSpeed * direction,
1194                                                                layoutSize,
1195                                                                *mActiveLayout);
1196
1197         if (mAnchoringEnabled)
1198         {
1199           firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(firstItemScrollPosition);
1200         }
1201
1202         RemoveAnimation(mScrollAnimation);
1203
1204         float flickAnimationDuration = Clamp( mActiveLayout->GetItemFlickAnimationDuration() * std::max(1.0f, fabsf(firstItemScrollPosition - GetCurrentLayoutPosition(0)))
1205                                        , DEFAULT_MINIMUM_SWIPE_DURATION, DEFAULT_MAXIMUM_SWIPE_DURATION);
1206
1207         mScrollAnimation = Animation::New(flickAnimationDuration);
1208         mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1209         mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1210         mScrollAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1211
1212         mIsFlicking = true;
1213         // Check whether it has already scrolled to the end
1214         if(fabs(currentLayoutPosition - firstItemScrollPosition) > Math::MACHINE_EPSILON_0)
1215         {
1216           AnimateScrollOvershoot(0.0f);
1217         }
1218       }
1219
1220       // Anchoring may be triggered when there was no swipe
1221       if (!mScrollAnimation)
1222       {
1223         mScrollAnimation = DoAnchoring();
1224       }
1225
1226       // Reset the overshoot if no scroll animation.
1227       if (!mScrollAnimation)
1228       {
1229         mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1230
1231         AnimateScrollOvershoot(0.0f, false);
1232       }
1233     }
1234     break;
1235
1236     case Gesture::Started: // Fall through
1237     {
1238       mTotalPanDisplacement = Vector2::ZERO;
1239       mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1240       mRefreshEnabled = true;
1241     }
1242
1243     case Gesture::Continuing:
1244     {
1245       mScrollDistance = CalculateScrollDistance(gesture.displacement, *mActiveLayout);
1246       mScrollSpeed = Clamp((gesture.GetSpeed() * gesture.GetSpeed() * mActiveLayout->GetFlickSpeedFactor() * MILLISECONDS_PER_SECONDS), 0.0f, mActiveLayout->GetMaximumSwipeSpeed());
1247
1248       // Refresh order depends on the direction of the scroll; negative is towards the last item.
1249       mRefreshOrderHint = mScrollDistance < 0.0f;
1250
1251       float layoutPositionDelta = GetCurrentLayoutPosition(0) + (mScrollDistance * mActiveLayout->GetScrollSpeedFactor());
1252
1253       float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1254
1255       mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1256       self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1257
1258       mTotalPanDisplacement += gesture.displacement;
1259       mScrollOvershoot = layoutPositionDelta - firstItemScrollPosition;
1260       if( mScrollOvershoot > Math::MACHINE_EPSILON_1 )
1261       {
1262         AnimateScrollOvershoot(1.0f);
1263       }
1264       else if( mScrollOvershoot < -Math::MACHINE_EPSILON_1 )
1265       {
1266         AnimateScrollOvershoot(-1.0f);
1267       }
1268       else
1269       {
1270         AnimateScrollOvershoot(0.0f);
1271       }
1272     }
1273     break;
1274
1275     case Gesture::Cancelled:
1276     {
1277       mScrollAnimation = DoAnchoring();
1278     }
1279     break;
1280
1281     default:
1282       break;
1283   }
1284
1285   if (mScrollAnimation)
1286   {
1287     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1288     mScrollAnimation.Play();
1289   }
1290 }
1291
1292 bool ItemView::OnAccessibilityPan(PanGesture gesture)
1293 {
1294   OnPan(gesture);
1295   return true;
1296 }
1297
1298 Actor ItemView::GetNextKeyboardFocusableActor(Actor actor, Toolkit::Control::KeyboardFocusNavigationDirection direction, bool loopEnabled)
1299 {
1300   Actor nextFocusActor;
1301   if(mActiveLayout)
1302   {
1303     int nextItemID = 0;
1304     if(!actor || actor == this->Self())
1305     {
1306       nextFocusActor = GetItem(nextItemID);
1307     }
1308     else if(actor && actor.GetParent() == this->Self())
1309     {
1310       int itemID = GetItemId(actor);
1311       nextItemID = mActiveLayout->GetNextFocusItemID(itemID, mItemFactory.GetNumberOfItems(), direction, loopEnabled);
1312       nextFocusActor = GetItem(nextItemID);
1313       if(nextFocusActor == actor)
1314       {
1315         // need to pass NULL actor back to focus manager
1316         nextFocusActor.Reset();
1317         return nextFocusActor;
1318       }
1319     }
1320     float layoutPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1321     Vector3 layoutSize = Self().GetCurrentSize();
1322     if(!nextFocusActor)
1323     {
1324       // likely the current item is not buffered, so not in our item pool, probably best to get first viewable item
1325       ItemRange viewableItems = mActiveLayout->GetItemsWithinArea(layoutPosition, layoutSize);
1326       nextItemID = viewableItems.begin;
1327       nextFocusActor = GetItem(nextItemID);
1328     }
1329   }
1330   return nextFocusActor;
1331 }
1332
1333 void ItemView::OnKeyboardFocusChangeCommitted(Actor commitedFocusableActor)
1334 {
1335   // only in this function if our chosen focus actor was actually used
1336   if(commitedFocusableActor)
1337   {
1338     int nextItemID = GetItemId(commitedFocusableActor);
1339     float layoutPosition = GetCurrentLayoutPosition(0);
1340     Vector3 layoutSize = Self().GetCurrentSize();
1341
1342     float scrollTo = mActiveLayout->GetClosestOnScreenLayoutPosition(nextItemID, layoutPosition, layoutSize);
1343     ScrollTo(Vector3(0.0f, scrollTo, 0.0f), DEFAULT_KEYBOARD_FOCUS_SCROLL_DURATION);
1344   }
1345 }
1346
1347 Animation ItemView::DoAnchoring()
1348 {
1349   Animation anchoringAnimation;
1350   Actor self = Self();
1351
1352   if (mActiveLayout && mAnchoringEnabled)
1353   {
1354     float anchorPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1355
1356     anchoringAnimation = Animation::New(mAnchoringDuration);
1357     anchoringAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), anchorPosition, AlphaFunctions::EaseOut );
1358     anchoringAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(anchorPosition, self.GetCurrentSize()), AlphaFunctions::EaseOut );
1359     anchoringAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1360     if(!mIsFlicking)
1361     {
1362       AnimateScrollOvershoot(0.0f);
1363     }
1364   }
1365
1366   return anchoringAnimation;
1367 }
1368
1369 void ItemView::OnScrollFinished(Animation& source)
1370 {
1371   Actor self = Self();
1372
1373   RemoveAnimation(mScrollAnimation); // mScrollAnimation is used to query whether we're scrolling
1374
1375   mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1376
1377   if(mIsFlicking && fabsf(mScrollOvershoot) > Math::MACHINE_EPSILON_1)
1378   {
1379     AnimateScrollOvershoot( mScrollOvershoot > 0.0f ? 1.0f : -1.0f, true);
1380   }
1381   else
1382   {
1383     // Reset the overshoot
1384     AnimateScrollOvershoot( 0.0f );
1385   }
1386   mIsFlicking = false;
1387
1388   mScrollOvershoot = 0.0f;
1389 }
1390
1391 void ItemView::OnLayoutActivationScrollFinished(Animation& source)
1392 {
1393   RemoveAnimation(mScrollAnimation);
1394   mRefreshEnabled = true;
1395   DoRefresh(GetCurrentLayoutPosition(0), true);
1396 }
1397
1398 void ItemView::OnOvershootOnFinished(Animation& animation)
1399 {
1400   mAnimatingOvershootOn = false;
1401   mScrollOvershootAnimation.FinishedSignal().Disconnect(this, &ItemView::OnOvershootOnFinished);
1402   RemoveAnimation(mScrollOvershootAnimation);
1403   if(mAnimateOvershootOff)
1404   {
1405     AnimateScrollOvershoot(0.0f);
1406   }
1407 }
1408
1409 void ItemView::ScrollToItem(unsigned int itemId, float durationSeconds)
1410 {
1411   Actor self = Self();
1412   const Vector3 layoutSize = Self().GetCurrentSize();
1413   float firstItemScrollPosition = ClampFirstItemPosition(mActiveLayout->GetItemScrollToPosition(itemId), layoutSize, *mActiveLayout);
1414
1415   if(durationSeconds > 0.0f)
1416   {
1417     RemoveAnimation(mScrollAnimation);
1418     mScrollAnimation = Animation::New(durationSeconds);
1419     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1420     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1421     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1422     mScrollAnimation.Play();
1423   }
1424   else
1425   {
1426     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1427     AnimateScrollOvershoot(0.0f);
1428   }
1429
1430   mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1431   mRefreshEnabled = true;
1432 }
1433
1434 void ItemView::RemoveAnimation(Animation& animation)
1435 {
1436   if(animation)
1437   {
1438     // Cease animating, and reset handle.
1439     animation.Clear();
1440     animation.Reset();
1441   }
1442 }
1443
1444 void ItemView::CalculateDomainSize(const Vector3& layoutSize)
1445 {
1446   Actor self = Self();
1447
1448   Vector3 firstItemPosition(Vector3::ZERO);
1449   Vector3 lastItemPosition(Vector3::ZERO);
1450
1451   if(mActiveLayout)
1452   {
1453     firstItemPosition = mActiveLayout->GetItemPosition( 0,0,layoutSize );
1454
1455     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), layoutSize);
1456     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1457     lastItemPosition = mActiveLayout->GetItemPosition( fabs(minLayoutPosition),fabs(minLayoutPosition),layoutSize );
1458
1459     float domainSize;
1460
1461     if(IsHorizontal(mActiveLayout->GetOrientation()))
1462     {
1463       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.x, 0.0f));
1464       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.x, 0.0f));
1465       domainSize = fabs(firstItemPosition.x - lastItemPosition.x);
1466     }
1467     else
1468     {
1469       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.y, 0.0f));
1470       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.y, 0.0f));
1471       domainSize = fabs(firstItemPosition.y - lastItemPosition.y);
1472     }
1473
1474     mScrollConnector.SetScrollDomain(minLayoutPosition, 0.0f, domainSize);
1475
1476     bool isLayoutScrollable = IsLayoutScrollable(layoutSize);
1477     self.SetProperty(mPropertyCanScrollVertical, isLayoutScrollable);
1478     self.SetProperty(mPropertyCanScrollHorizontal, false);
1479   }
1480 }
1481
1482 Vector3 ItemView::GetDomainSize() const
1483 {
1484   Actor self = Self();
1485
1486   float minScrollPosition = self.GetProperty<float>(mPropertyPositionMin);
1487   float maxScrollPosition = self.GetProperty<float>(mPropertyPositionMax);
1488
1489   return Vector3(0.0f, fabs(maxScrollPosition - minScrollPosition), 0.0f);
1490 }
1491
1492 bool ItemView::IsLayoutScrollable(const Vector3& layoutSize)
1493 {
1494   Actor self = Self();
1495
1496   float currentLayoutPosition = ClampFirstItemPosition( GetCurrentLayoutPosition(0), layoutSize, *mActiveLayout );
1497   float forwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition + 1.0, layoutSize, *mActiveLayout);
1498   float backwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition - 1.0, layoutSize, *mActiveLayout);
1499
1500   return (fabs(forwardClampedPosition - backwardClampedPosition) > Math::MACHINE_EPSILON_0);
1501 }
1502
1503 float ItemView::GetScrollPosition(float layoutPosition, const Vector3& layoutSize) const
1504 {
1505   Vector3 firstItemPosition( mActiveLayout->GetItemPosition(0, layoutPosition, layoutSize ) );
1506   return IsHorizontal(mActiveLayout->GetOrientation()) ? firstItemPosition.x: firstItemPosition.y;
1507 }
1508
1509 Vector3 ItemView::GetCurrentScrollPosition() const
1510 {
1511   float currentLayoutPosition = GetCurrentLayoutPosition(0);
1512   return Vector3(0.0f, GetScrollPosition(currentLayoutPosition, Self().GetCurrentSize()), 0.0f);
1513 }
1514
1515 void ItemView::AddOverlay(Actor actor)
1516 {
1517   Self().Add(actor);
1518 }
1519
1520 void ItemView::RemoveOverlay(Actor actor)
1521 {
1522   Self().Remove(actor);
1523 }
1524
1525 void ItemView::ScrollTo(const Vector3& position, float duration)
1526 {
1527   Actor self = Self();
1528   const Vector3 layoutSize = Self().GetCurrentSize();
1529
1530   float firstItemScrollPosition = ClampFirstItemPosition(position.y, layoutSize, *mActiveLayout);
1531
1532   if(duration > 0.0f)
1533   {
1534     RemoveAnimation(mScrollAnimation);
1535     mScrollAnimation = Animation::New(duration);
1536     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1537     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1538     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1539     mScrollAnimation.Play();
1540   }
1541   else
1542   {
1543     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1544     AnimateScrollOvershoot(0.0f);
1545   }
1546
1547   mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1548   mRefreshEnabled = true;
1549 }
1550
1551 void ItemView::SetOvershootEffectColor( const Vector4& color )
1552 {
1553   mOvershootEffectColor = color;
1554   if( mOvershootOverlay )
1555   {
1556     mOvershootOverlay.SetColor( color );
1557   }
1558 }
1559
1560 void ItemView::SetOvershootEnabled( bool enable )
1561 {
1562   Actor self = Self();
1563   if( enable )
1564   {
1565     Property::Index effectOvershootPropertyIndex = Property::INVALID_INDEX;
1566     mOvershootOverlay = CreateBouncingEffectActor( effectOvershootPropertyIndex );
1567     mOvershootOverlay.SetColor(mOvershootEffectColor);
1568     mOvershootOverlay.SetParentOrigin(ParentOrigin::TOP_LEFT);
1569     mOvershootOverlay.SetAnchorPoint(AnchorPoint::TOP_LEFT);
1570     mOvershootOverlay.SetDrawMode(DrawMode::OVERLAY);
1571     self.Add(mOvershootOverlay);
1572
1573     Constraint constraint = Constraint::New<Vector3>( Actor::SIZE,
1574                                                       ParentSource( mPropertyScrollDirection ),
1575                                                       Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1576                                                       ParentSource( Actor::SIZE ),
1577                                                       OvershootOverlaySizeConstraint() );
1578     mOvershootOverlay.ApplyConstraint(constraint);
1579     mOvershootOverlay.SetSize(OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.width, OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height);
1580
1581     constraint = Constraint::New<Quaternion>( Actor::ROTATION,
1582                                               ParentSource( mPropertyScrollDirection ),
1583                                               Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1584                                               OvershootOverlayRotationConstraint() );
1585     mOvershootOverlay.ApplyConstraint(constraint);
1586
1587     constraint = Constraint::New<Vector3>( Actor::POSITION,
1588                                            ParentSource( Actor::SIZE ),
1589                                            ParentSource( mPropertyScrollDirection ),
1590                                            Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1591                                            OvershootOverlayPositionConstraint() );
1592     mOvershootOverlay.ApplyConstraint(constraint);
1593
1594     constraint = Constraint::New<bool>( Actor::VISIBLE,
1595                                         ParentSource( mPropertyCanScrollVertical ),
1596                                         OvershootOverlayVisibilityConstraint() );
1597     mOvershootOverlay.ApplyConstraint(constraint);
1598
1599     Actor self = Self();
1600     constraint = Constraint::New<float>( effectOvershootPropertyIndex,
1601                                          Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1602                                          EqualToConstraint() );
1603     mOvershootOverlay.ApplyConstraint(constraint);
1604   }
1605   else
1606   {
1607     if( mOvershootOverlay )
1608     {
1609       self.Remove(mOvershootOverlay);
1610       mOvershootOverlay.Reset();
1611     }
1612   }
1613 }
1614
1615 float ItemView::CalculateScrollOvershoot()
1616 {
1617   float overshoot = 0.0f;
1618
1619   if(mActiveLayout)
1620   {
1621     // The overshoot must be calculated from the accumulated pan gesture displacement
1622     // since the pan gesture starts.
1623     Actor self = Self();
1624     float scrollDistance = CalculateScrollDistance(mTotalPanDisplacement, *mActiveLayout) * mActiveLayout->GetScrollSpeedFactor();
1625     float positionDelta = GetCurrentLayoutPosition(0) + scrollDistance;
1626     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), Self().GetCurrentSize());
1627     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1628     float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, positionDelta));
1629     overshoot = positionDelta - clamppedPosition;
1630   }
1631
1632   return overshoot;
1633 }
1634
1635 void ItemView::AnimateScrollOvershoot(float overshootAmount, bool animateBack)
1636 {
1637   bool animatingOn = fabsf(overshootAmount) > Math::MACHINE_EPSILON_1;
1638
1639   // make sure we animate back if needed
1640   mAnimateOvershootOff = animateBack || (!animatingOn && mAnimatingOvershootOn);
1641
1642   if( mAnimatingOvershootOn )
1643   {
1644     // animating on, do not allow animate off
1645     return;
1646   }
1647
1648   Actor self = Self();
1649   float currentOvershoot = mScrollPositionObject.GetProperty<float>(ScrollConnector::OVERSHOOT);
1650   float duration = DEFAULT_OVERSHOOT_ANIMATION_DURATION * (animatingOn ? (1.0f - fabsf(currentOvershoot)) : fabsf(currentOvershoot));
1651
1652   RemoveAnimation(mScrollOvershootAnimation);
1653   mScrollOvershootAnimation = Animation::New(duration);
1654   mScrollOvershootAnimation.FinishedSignal().Connect(this, &ItemView::OnOvershootOnFinished);
1655   mScrollOvershootAnimation.AnimateTo( Property(mScrollPositionObject, ScrollConnector::OVERSHOOT), overshootAmount, TimePeriod(0.0f, duration) );
1656   mScrollOvershootAnimation.Play();
1657
1658   mAnimatingOvershootOn = animatingOn;
1659 }
1660
1661 void ItemView::SetItemsParentOrigin( const Vector3& parentOrigin )
1662 {
1663   if( parentOrigin != mItemsParentOrigin )
1664   {
1665     mItemsParentOrigin = parentOrigin;
1666     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1667     {
1668       iter->second.SetParentOrigin(parentOrigin);
1669     }
1670   }
1671 }
1672
1673 Vector3 ItemView::GetItemsParentOrigin() const
1674 {
1675   return mItemsParentOrigin;
1676 }
1677
1678 void ItemView::SetItemsAnchorPoint( const Vector3& anchorPoint )
1679 {
1680   if( anchorPoint != mItemsAnchorPoint )
1681   {
1682     mItemsAnchorPoint = anchorPoint;
1683     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1684     {
1685       iter->second.SetAnchorPoint(anchorPoint);
1686     }
1687   }
1688 }
1689
1690 Vector3 ItemView::GetItemsAnchorPoint() const
1691 {
1692   return mItemsAnchorPoint;
1693 }
1694
1695 void ItemView::GetItemsRange(ItemRange& range)
1696 {
1697   if( !mItemPool.empty() )
1698   {
1699     range.begin = mItemPool.begin()->first;
1700     range.end = mItemPool.rbegin()->first + 1;
1701   }
1702   else
1703   {
1704     range.begin = 0;
1705     range.end = 0;
1706   }
1707 }
1708
1709 void ItemView::OnScrollPositionChanged( float position )
1710 {
1711   // Cancel scroll animation to prevent any fighting of setting the scroll position property.
1712   RemoveAnimation(mScrollAnimation);
1713
1714   // Refresh the cache immediately when the scroll position is changed.
1715   DoRefresh(position, false); // No need to cache extra items.
1716 }
1717
1718 } // namespace Internal
1719
1720 } // namespace Toolkit
1721
1722 } // namespace Dali