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     ItemPool::reverse_iterator lastIter = mItemPool.rbegin();
 732     if ( lastIter != mItemPool.rend() )
 733     {
 734       ItemId lastId = lastIter->first;
 735       Item lastItem( lastId + 1, displacedActor );
 736       mItemPool.insert( lastItem );
 737
 738       lastItem.second.RemoveConstraints();
 739       mActiveLayout->ApplyConstraints( lastItem.second, lastItem.first, durationSeconds, mScrollPositionObject, Self() );
 740     }
 741   }
 742
 743   CalculateDomainSize(Self().GetCurrentSize());
 744
 745   mAddingItems = false;
 746 }
 747
 748 void ItemView::InsertItems( const ItemContainer& newItems, float durationSeconds )
 749 {
 750   mAddingItems = true;
 751
 752   // Insert from lowest id to highest
 753   std::set<Item> sortedItems;
 754   for( ConstItemIter iter = newItems.begin(); newItems.end() != iter; ++iter )
 755   {
 756     sortedItems.insert( *iter );
 757   }
 758
 759   for( std::set<Item>::iterator iter = sortedItems.begin(); sortedItems.end() != iter; ++iter )
 760   {
 761     Self().Add( iter->second );
 762
 763     ItemPoolIter foundIter = mItemPool.find( iter->first );
 764     if( mItemPool.end() != foundIter )
 765     {
 766       Actor moveMe = foundIter->second;
 767       foundIter->second = iter->second;
 768
 769       // Move the existing actors to make room
 770       for( ItemPoolIter iter = ++foundIter; mItemPool.end() != iter; ++iter )
 771       {
 772         Actor temp = iter->second;
 773         iter->second = moveMe;
 774         moveMe = temp;
 775       }
 776
 777       // Create last item
 778       ItemId lastId = mItemPool.rbegin()->first;
 779       Item lastItem( lastId + 1, moveMe );
 780       mItemPool.insert( lastItem );
 781     }
 782     else
 783     {
 784       mItemPool.insert( *iter );
 785     }
 786   }
 787
 788   // Relayout everything
 789   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 790   {
 791     // If newly inserted
 792     if( FindById( newItems, iter->first ) )
 793     {
 794       SetupActor( *iter, durationSeconds );
 795     }
 796     else
 797     {
 798       iter->second.RemoveConstraints();
 799       mActiveLayout->ApplyConstraints( iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 800     }
 801   }
 802
 803   CalculateDomainSize(Self().GetCurrentSize());
 804
 805   mAddingItems = false;
 806 }
 807
 808 void ItemView::RemoveItem( unsigned int itemId, float durationSeconds )
 809 {
 810   bool actorsReordered = RemoveActor( itemId );
 811   if( actorsReordered )
 812   {
 813     ReapplyAllConstraints( durationSeconds );
 814
 815     OnItemsRemoved();
 816   }
 817 }
 818
 819 void ItemView::RemoveItems( const ItemIdContainer& itemIds, float durationSeconds )
 820 {
 821   bool actorsReordered( false );
 822
 823   // Remove from highest id to lowest
 824   set<ItemId> sortedItems;
 825   for( ConstItemIdIter iter = itemIds.begin(); itemIds.end() != iter; ++iter )
 826   {
 827     sortedItems.insert( *iter );
 828   }
 829
 830   for( set<ItemId>::reverse_iterator iter = sortedItems.rbegin(); sortedItems.rend() != iter; ++iter )
 831   {
 832     if( RemoveActor( *iter ) )
 833     {
 834       actorsReordered = true;
 835     }
 836   }
 837
 838   if( actorsReordered )
 839   {
 840     ReapplyAllConstraints( durationSeconds );
 841
 842     OnItemsRemoved();
 843   }
 844 }
 845
 846 bool ItemView::RemoveActor(unsigned int itemId)
 847 {
 848   bool reordered( false );
 849
 850   ItemPoolIter removeIter = mItemPool.find( itemId );
 851   if( removeIter != mItemPool.end() )
 852   {
 853     ReleaseActor(itemId, removeIter->second);
 854   }
 855   else
 856   {
 857     // Removing before the existing item range?
 858     ItemPoolIter iter = mItemPool.begin();
 859     if( iter != mItemPool.end() &&
 860         iter->first > itemId )
 861     {
 862       // In order to decrement the first visible item ID
 863       mItemPool.insert( Item(iter->first - 1, Actor()) );
 864
 865       removeIter = mItemPool.begin();
 866     }
 867   }
 868
 869   if( removeIter != mItemPool.end() )
 870   {
 871     reordered = true;
 872
 873     // Adjust the remaining item IDs, for example if item 2 is removed:
 874     //   Initial actors:     After insert:
 875     //     ID 1 - ActorA       ID 1 - ActorA
 876     //     ID 2 - ActorB       ID 2 - ActorC (previously ID 3)
 877     //     ID 3 - ActorC       ID 3 - ActorB (previously ID 4)
 878     //     ID 4 - ActorD
 879     for (ItemPoolIter iter = removeIter; iter != mItemPool.end(); ++iter)
 880     {
 881       if( iter->first < mItemPool.rbegin()->first )
 882       {
 883         iter->second = mItemPool[ iter->first + 1 ];
 884       }
 885       else
 886       {
 887         mItemPool.erase( iter );
 888         break;
 889       }
 890     }
 891   }
 892
 893   return reordered;
 894 }
 895
 896 void ItemView::ReplaceItem( Item replacementItem, float durationSeconds )
 897 {
 898   mAddingItems = true;
 899
 900   SetupActor( replacementItem, durationSeconds );
 901   Self().Add( replacementItem.second );
 902
 903   const ItemPoolIter iter = mItemPool.find( replacementItem.first );
 904   if( mItemPool.end() != iter )
 905   {
 906     ReleaseActor(iter->first, iter->second);
 907     iter->second = replacementItem.second;
 908   }
 909   else
 910   {
 911     mItemPool.insert( replacementItem );
 912   }
 913
 914   CalculateDomainSize(Self().GetCurrentSize());
 915
 916   mAddingItems = false;
 917 }
 918
 919 void ItemView::ReplaceItems( const ItemContainer& replacementItems, float durationSeconds )
 920 {
 921   for( ConstItemIter iter = replacementItems.begin(); replacementItems.end() != iter; ++iter )
 922   {
 923     ReplaceItem( *iter, durationSeconds );
 924   }
 925 }
 926
 927 void ItemView::RemoveActorsOutsideRange( ItemRange range )
 928 {
 929   // Remove unwanted actors from the ItemView & ItemPool
 930   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); )
 931   {
 932     unsigned int current = iter->first;
 933
 934     if( ! range.Within( current ) )
 935     {
 936       ReleaseActor(iter->first, iter->second);
 937
 938       mItemPool.erase( iter++ ); // erase invalidates the return value of post-increment; iter remains valid
 939     }
 940     else
 941     {
 942       ++iter;
 943     }
 944   }
 945 }
 946
 947 void ItemView::AddActorsWithinRange( ItemRange range, float durationSeconds )
 948 {
 949   range.end = std::min(mItemFactory.GetNumberOfItems(), range.end);
 950
 951   // The order of addition depends on the scroll direction.
 952   if (mRefreshOrderHint)
 953   {
 954     for (unsigned int itemId = range.begin; itemId < range.end; ++itemId)
 955     {
 956       AddNewActor( itemId, durationSeconds );
 957     }
 958   }
 959   else
 960   {
 961     for (unsigned int itemId = range.end; itemId > range.begin; --itemId)
 962     {
 963       AddNewActor( itemId-1, durationSeconds );
 964     }
 965   }
 966
 967   // Total number of items may change dynamically.
 968   // Always recalculate the domain size to reflect that.
 969   CalculateDomainSize(Self().GetCurrentSize());
 970 }
 971
 972 void ItemView::AddNewActor( unsigned int itemId, float durationSeconds )
 973 {
 974   mAddingItems = true;
 975
 976   if( mItemPool.end() == mItemPool.find( itemId ) )
 977   {
 978     Actor actor = mItemFactory.NewItem( itemId );
 979
 980     if( actor )
 981     {
 982       Item newItem( itemId, actor );
 983
 984       mItemPool.insert( newItem );
 985
 986       SetupActor( newItem, durationSeconds );
 987       Self().Add( actor );
 988     }
 989   }
 990
 991   mAddingItems = false;
 992 }
 993
 994 void ItemView::SetupActor( Item item, float durationSeconds )
 995 {
 996   item.second.SetParentOrigin( mItemsParentOrigin );
 997   item.second.SetAnchorPoint( mItemsAnchorPoint );
 998
 999   if( mActiveLayout )
1000   {
1001     Vector3 size;
1002     if( mActiveLayout->GetItemSize( item.first, mActiveLayoutTargetSize, size ) )
1003     {
1004       item.second.SetSize( size );
1005     }
1006
1007     mActiveLayout->ApplyConstraints( item.second, item.first, durationSeconds, mScrollPositionObject, Self() );
1008   }
1009 }
1010
1011 void ItemView::ReleaseActor( ItemId item, Actor actor )
1012 {
1013   Self().Remove( actor );
1014   mItemFactory.ItemReleased(item, actor);
1015 }
1016
1017 ItemRange ItemView::GetItemRange(ItemLayout& layout, const Vector3& layoutSize, float layoutPosition, bool reserveExtra)
1018 {
1019   unsigned int itemCount = mItemFactory.GetNumberOfItems();
1020
1021   ItemRange available(0u, itemCount);
1022
1023   ItemRange range = layout.GetItemsWithinArea( layoutPosition, layoutSize );
1024
1025   if (reserveExtra)
1026   {
1027     // Add the reserve items for scrolling
1028     unsigned int extra = layout.GetReserveItemCount(layoutSize);
1029     range.begin = (range.begin >= extra) ? (range.begin - extra) : 0u;
1030     range.end += extra;
1031   }
1032
1033   return range.Intersection(available);
1034 }
1035
1036 void ItemView::OnChildAdd(Actor& child)
1037 {
1038   if(!mAddingItems)
1039   {
1040     // We don't want to do this downcast check for any item added by ItemView itself.
1041     Dali::Toolkit::ScrollComponent scrollComponent = Dali::Toolkit::ScrollComponent::DownCast(child);
1042     if(scrollComponent)
1043     {
1044       // Set the scroll connector when scroll bar is being added
1045       scrollComponent.SetScrollConnector(mScrollConnector);
1046     }
1047   }
1048 }
1049
1050 bool ItemView::OnTouchEvent(const TouchEvent& event)
1051 {
1052   // Ignore events with multiple-touch points
1053   if (event.GetPointCount() != 1)
1054   {
1055     return false;
1056   }
1057
1058   if (event.GetPoint(0).state == TouchPoint::Down)
1059   {
1060     // Cancel ongoing scrolling etc.
1061     mGestureState = Gesture::Clear;
1062
1063     mScrollDistance = 0.0f;
1064     mScrollSpeed = 0.0f;
1065     Self().SetProperty(mPropertyScrollSpeed, mScrollSpeed);
1066
1067     mScrollOvershoot = 0.0f;
1068     AnimateScrollOvershoot(0.0f);
1069
1070     if(mScrollAnimation)
1071     {
1072       mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1073     }
1074
1075     RemoveAnimation(mScrollAnimation);
1076   }
1077
1078   return true; // consume since we're potentially scrolling
1079 }
1080
1081 bool ItemView::OnMouseWheelEvent(const MouseWheelEvent& event)
1082 {
1083   // Respond the mouse wheel event to scroll
1084   if (mActiveLayout)
1085   {
1086     Actor self = Self();
1087     const Vector3 layoutSize = Self().GetCurrentSize();
1088     float layoutPositionDelta = GetCurrentLayoutPosition(0) - (event.z * mMouseWheelScrollDistanceStep * mActiveLayout->GetScrollSpeedFactor());
1089     float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1090
1091     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1092     self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1093     mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1094     mRefreshEnabled = true;
1095   }
1096
1097   if (mMouseWheelEventFinishedTimer.IsRunning())
1098   {
1099     mMouseWheelEventFinishedTimer.Stop();
1100   }
1101
1102   mMouseWheelEventFinishedTimer.Start();
1103
1104   return true;
1105 }
1106
1107 bool ItemView::OnMouseWheelEventFinished()
1108 {
1109   if (mActiveLayout)
1110   {
1111     RemoveAnimation(mScrollAnimation);
1112
1113     // No more mouse wheel events coming. Do the anchoring if enabled.
1114     mScrollAnimation = DoAnchoring();
1115     if (mScrollAnimation)
1116     {
1117       mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1118       mScrollAnimation.Play();
1119     }
1120     else
1121     {
1122       mScrollOvershoot = 0.0f;
1123       AnimateScrollOvershoot(0.0f);
1124
1125       mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1126     }
1127   }
1128
1129   return false;
1130 }
1131
1132 void ItemView::ReapplyAllConstraints( float durationSeconds )
1133 {
1134   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1135   {
1136     unsigned int id = iter->first;
1137     Actor actor = iter->second;
1138
1139     actor.RemoveConstraints();
1140     mActiveLayout->ApplyConstraints(actor, id, durationSeconds, mScrollPositionObject, Self());
1141   }
1142 }
1143
1144 void ItemView::OnItemsRemoved()
1145 {
1146   CalculateDomainSize(Self().GetCurrentSize());
1147
1148   // Adjust scroll-position after an item is removed
1149   if( mActiveLayout )
1150   {
1151     float firstItemScrollPosition = ClampFirstItemPosition(GetCurrentLayoutPosition(0), Self().GetCurrentSize(), *mActiveLayout);
1152
1153     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1154   }
1155 }
1156
1157 float ItemView::ClampFirstItemPosition(float targetPosition, const Vector3& targetSize, ItemLayout& layout)
1158 {
1159   Actor self = Self();
1160   float minLayoutPosition = layout.GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize);
1161   float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, targetPosition));
1162   mScrollOvershoot = targetPosition - clamppedPosition;
1163   self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1164
1165   return clamppedPosition;
1166 }
1167
1168 void ItemView::OnPan( const PanGesture& gesture )
1169 {
1170   Actor self = Self();
1171   const Vector3 layoutSize = Self().GetCurrentSize();
1172
1173   RemoveAnimation(mScrollAnimation);
1174
1175   // Short-circuit if there is no active layout
1176   if (!mActiveLayout)
1177   {
1178     mGestureState = Gesture::Clear;
1179     return;
1180   }
1181
1182   mGestureState = gesture.state;
1183
1184   switch (mGestureState)
1185   {
1186     case Gesture::Finished:
1187     {
1188       // Swipe Detection
1189       if (fabsf(mScrollDistance) > mMinimumSwipeDistance &&
1190           mScrollSpeed > mMinimumSwipeSpeed)
1191       {
1192         float direction = (mScrollDistance < 0.0f) ? -1.0f : 1.0f;
1193
1194         mRefreshOrderHint = true;
1195
1196         float currentLayoutPosition = GetCurrentLayoutPosition(0);
1197         float firstItemScrollPosition = ClampFirstItemPosition(currentLayoutPosition + mScrollSpeed * direction,
1198                                                                layoutSize,
1199                                                                *mActiveLayout);
1200
1201         if (mAnchoringEnabled)
1202         {
1203           firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(firstItemScrollPosition);
1204         }
1205
1206         RemoveAnimation(mScrollAnimation);
1207
1208         float flickAnimationDuration = Clamp( mActiveLayout->GetItemFlickAnimationDuration() * std::max(1.0f, fabsf(firstItemScrollPosition - GetCurrentLayoutPosition(0)))
1209                                        , DEFAULT_MINIMUM_SWIPE_DURATION, DEFAULT_MAXIMUM_SWIPE_DURATION);
1210
1211         mScrollAnimation = Animation::New(flickAnimationDuration);
1212         mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1213         mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1214         mScrollAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1215
1216         mIsFlicking = true;
1217         // Check whether it has already scrolled to the end
1218         if(fabs(currentLayoutPosition - firstItemScrollPosition) > Math::MACHINE_EPSILON_0)
1219         {
1220           AnimateScrollOvershoot(0.0f);
1221         }
1222       }
1223
1224       // Anchoring may be triggered when there was no swipe
1225       if (!mScrollAnimation)
1226       {
1227         mScrollAnimation = DoAnchoring();
1228       }
1229
1230       // Reset the overshoot if no scroll animation.
1231       if (!mScrollAnimation)
1232       {
1233         mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1234
1235         AnimateScrollOvershoot(0.0f, false);
1236       }
1237     }
1238     break;
1239
1240     case Gesture::Started: // Fall through
1241     {
1242       mTotalPanDisplacement = Vector2::ZERO;
1243       mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1244       mRefreshEnabled = true;
1245     }
1246
1247     case Gesture::Continuing:
1248     {
1249       mScrollDistance = CalculateScrollDistance(gesture.displacement, *mActiveLayout);
1250       mScrollSpeed = Clamp((gesture.GetSpeed() * gesture.GetSpeed() * mActiveLayout->GetFlickSpeedFactor() * MILLISECONDS_PER_SECONDS), 0.0f, mActiveLayout->GetMaximumSwipeSpeed());
1251
1252       // Refresh order depends on the direction of the scroll; negative is towards the last item.
1253       mRefreshOrderHint = mScrollDistance < 0.0f;
1254
1255       float layoutPositionDelta = GetCurrentLayoutPosition(0) + (mScrollDistance * mActiveLayout->GetScrollSpeedFactor());
1256
1257       float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1258
1259       mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1260       self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1261
1262       mTotalPanDisplacement += gesture.displacement;
1263       mScrollOvershoot = layoutPositionDelta - firstItemScrollPosition;
1264       if( mScrollOvershoot > Math::MACHINE_EPSILON_1 )
1265       {
1266         AnimateScrollOvershoot(1.0f);
1267       }
1268       else if( mScrollOvershoot < -Math::MACHINE_EPSILON_1 )
1269       {
1270         AnimateScrollOvershoot(-1.0f);
1271       }
1272       else
1273       {
1274         AnimateScrollOvershoot(0.0f);
1275       }
1276     }
1277     break;
1278
1279     case Gesture::Cancelled:
1280     {
1281       mScrollAnimation = DoAnchoring();
1282     }
1283     break;
1284
1285     default:
1286       break;
1287   }
1288
1289   if (mScrollAnimation)
1290   {
1291     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1292     mScrollAnimation.Play();
1293   }
1294 }
1295
1296 bool ItemView::OnAccessibilityPan(PanGesture gesture)
1297 {
1298   OnPan(gesture);
1299   return true;
1300 }
1301
1302 Actor ItemView::GetNextKeyboardFocusableActor(Actor actor, Toolkit::Control::KeyboardFocusNavigationDirection direction, bool loopEnabled)
1303 {
1304   Actor nextFocusActor;
1305   if(mActiveLayout)
1306   {
1307     int nextItemID = 0;
1308     if(!actor || actor == this->Self())
1309     {
1310       nextFocusActor = GetItem(nextItemID);
1311     }
1312     else if(actor && actor.GetParent() == this->Self())
1313     {
1314       int itemID = GetItemId(actor);
1315       nextItemID = mActiveLayout->GetNextFocusItemID(itemID, mItemFactory.GetNumberOfItems(), direction, loopEnabled);
1316       nextFocusActor = GetItem(nextItemID);
1317       if(nextFocusActor == actor)
1318       {
1319         // need to pass NULL actor back to focus manager
1320         nextFocusActor.Reset();
1321         return nextFocusActor;
1322       }
1323     }
1324     float layoutPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1325     Vector3 layoutSize = Self().GetCurrentSize();
1326     if(!nextFocusActor)
1327     {
1328       // likely the current item is not buffered, so not in our item pool, probably best to get first viewable item
1329       ItemRange viewableItems = mActiveLayout->GetItemsWithinArea(layoutPosition, layoutSize);
1330       nextItemID = viewableItems.begin;
1331       nextFocusActor = GetItem(nextItemID);
1332     }
1333   }
1334   return nextFocusActor;
1335 }
1336
1337 void ItemView::OnKeyboardFocusChangeCommitted(Actor commitedFocusableActor)
1338 {
1339   // only in this function if our chosen focus actor was actually used
1340   if(commitedFocusableActor)
1341   {
1342     int nextItemID = GetItemId(commitedFocusableActor);
1343     float layoutPosition = GetCurrentLayoutPosition(0);
1344     Vector3 layoutSize = Self().GetCurrentSize();
1345
1346     float scrollTo = mActiveLayout->GetClosestOnScreenLayoutPosition(nextItemID, layoutPosition, layoutSize);
1347     ScrollTo(Vector3(0.0f, scrollTo, 0.0f), DEFAULT_KEYBOARD_FOCUS_SCROLL_DURATION);
1348   }
1349 }
1350
1351 Animation ItemView::DoAnchoring()
1352 {
1353   Animation anchoringAnimation;
1354   Actor self = Self();
1355
1356   if (mActiveLayout && mAnchoringEnabled)
1357   {
1358     float anchorPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1359
1360     anchoringAnimation = Animation::New(mAnchoringDuration);
1361     anchoringAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), anchorPosition, AlphaFunctions::EaseOut );
1362     anchoringAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(anchorPosition, self.GetCurrentSize()), AlphaFunctions::EaseOut );
1363     anchoringAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1364     if(!mIsFlicking)
1365     {
1366       AnimateScrollOvershoot(0.0f);
1367     }
1368   }
1369
1370   return anchoringAnimation;
1371 }
1372
1373 void ItemView::OnScrollFinished(Animation& source)
1374 {
1375   Actor self = Self();
1376
1377   RemoveAnimation(mScrollAnimation); // mScrollAnimation is used to query whether we're scrolling
1378
1379   mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1380
1381   if(mIsFlicking && fabsf(mScrollOvershoot) > Math::MACHINE_EPSILON_1)
1382   {
1383     AnimateScrollOvershoot( mScrollOvershoot > 0.0f ? 1.0f : -1.0f, true);
1384   }
1385   else
1386   {
1387     // Reset the overshoot
1388     AnimateScrollOvershoot( 0.0f );
1389   }
1390   mIsFlicking = false;
1391
1392   mScrollOvershoot = 0.0f;
1393 }
1394
1395 void ItemView::OnLayoutActivationScrollFinished(Animation& source)
1396 {
1397   RemoveAnimation(mScrollAnimation);
1398   mRefreshEnabled = true;
1399   DoRefresh(GetCurrentLayoutPosition(0), true);
1400 }
1401
1402 void ItemView::OnOvershootOnFinished(Animation& animation)
1403 {
1404   mAnimatingOvershootOn = false;
1405   mScrollOvershootAnimation.FinishedSignal().Disconnect(this, &ItemView::OnOvershootOnFinished);
1406   RemoveAnimation(mScrollOvershootAnimation);
1407   if(mAnimateOvershootOff)
1408   {
1409     AnimateScrollOvershoot(0.0f);
1410   }
1411 }
1412
1413 void ItemView::ScrollToItem(unsigned int itemId, float durationSeconds)
1414 {
1415   Actor self = Self();
1416   const Vector3 layoutSize = Self().GetCurrentSize();
1417   float firstItemScrollPosition = ClampFirstItemPosition(mActiveLayout->GetItemScrollToPosition(itemId), layoutSize, *mActiveLayout);
1418
1419   if(durationSeconds > 0.0f)
1420   {
1421     RemoveAnimation(mScrollAnimation);
1422     mScrollAnimation = Animation::New(durationSeconds);
1423     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1424     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1425     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1426     mScrollAnimation.Play();
1427   }
1428   else
1429   {
1430     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1431     AnimateScrollOvershoot(0.0f);
1432   }
1433
1434   mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1435   mRefreshEnabled = true;
1436 }
1437
1438 void ItemView::RemoveAnimation(Animation& animation)
1439 {
1440   if(animation)
1441   {
1442     // Cease animating, and reset handle.
1443     animation.Clear();
1444     animation.Reset();
1445   }
1446 }
1447
1448 void ItemView::CalculateDomainSize(const Vector3& layoutSize)
1449 {
1450   Actor self = Self();
1451
1452   Vector3 firstItemPosition(Vector3::ZERO);
1453   Vector3 lastItemPosition(Vector3::ZERO);
1454
1455   if(mActiveLayout)
1456   {
1457     firstItemPosition = mActiveLayout->GetItemPosition( 0,0,layoutSize );
1458
1459     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), layoutSize);
1460     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1461     lastItemPosition = mActiveLayout->GetItemPosition( fabs(minLayoutPosition),fabs(minLayoutPosition),layoutSize );
1462
1463     float domainSize;
1464
1465     if(IsHorizontal(mActiveLayout->GetOrientation()))
1466     {
1467       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.x, 0.0f));
1468       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.x, 0.0f));
1469       domainSize = fabs(firstItemPosition.x - lastItemPosition.x);
1470     }
1471     else
1472     {
1473       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.y, 0.0f));
1474       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.y, 0.0f));
1475       domainSize = fabs(firstItemPosition.y - lastItemPosition.y);
1476     }
1477
1478     mScrollConnector.SetScrollDomain(minLayoutPosition, 0.0f, domainSize);
1479
1480     bool isLayoutScrollable = IsLayoutScrollable(layoutSize);
1481     self.SetProperty(mPropertyCanScrollVertical, isLayoutScrollable);
1482     self.SetProperty(mPropertyCanScrollHorizontal, false);
1483   }
1484 }
1485
1486 Vector3 ItemView::GetDomainSize() const
1487 {
1488   Actor self = Self();
1489
1490   float minScrollPosition = self.GetProperty<float>(mPropertyPositionMin);
1491   float maxScrollPosition = self.GetProperty<float>(mPropertyPositionMax);
1492
1493   return Vector3(0.0f, fabs(maxScrollPosition - minScrollPosition), 0.0f);
1494 }
1495
1496 bool ItemView::IsLayoutScrollable(const Vector3& layoutSize)
1497 {
1498   Actor self = Self();
1499
1500   float currentLayoutPosition = ClampFirstItemPosition( GetCurrentLayoutPosition(0), layoutSize, *mActiveLayout );
1501   float forwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition + 1.0, layoutSize, *mActiveLayout);
1502   float backwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition - 1.0, layoutSize, *mActiveLayout);
1503
1504   return (fabs(forwardClampedPosition - backwardClampedPosition) > Math::MACHINE_EPSILON_0);
1505 }
1506
1507 float ItemView::GetScrollPosition(float layoutPosition, const Vector3& layoutSize) const
1508 {
1509   Vector3 firstItemPosition( mActiveLayout->GetItemPosition(0, layoutPosition, layoutSize ) );
1510   return IsHorizontal(mActiveLayout->GetOrientation()) ? firstItemPosition.x: firstItemPosition.y;
1511 }
1512
1513 Vector3 ItemView::GetCurrentScrollPosition() const
1514 {
1515   float currentLayoutPosition = GetCurrentLayoutPosition(0);
1516   return Vector3(0.0f, GetScrollPosition(currentLayoutPosition, Self().GetCurrentSize()), 0.0f);
1517 }
1518
1519 void ItemView::AddOverlay(Actor actor)
1520 {
1521   Self().Add(actor);
1522 }
1523
1524 void ItemView::RemoveOverlay(Actor actor)
1525 {
1526   Self().Remove(actor);
1527 }
1528
1529 void ItemView::ScrollTo(const Vector3& position, float duration)
1530 {
1531   Actor self = Self();
1532   const Vector3 layoutSize = Self().GetCurrentSize();
1533
1534   float firstItemScrollPosition = ClampFirstItemPosition(position.y, layoutSize, *mActiveLayout);
1535
1536   if(duration > 0.0f)
1537   {
1538     RemoveAnimation(mScrollAnimation);
1539     mScrollAnimation = Animation::New(duration);
1540     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1541     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1542     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1543     mScrollAnimation.Play();
1544   }
1545   else
1546   {
1547     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1548     AnimateScrollOvershoot(0.0f);
1549   }
1550
1551   mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1552   mRefreshEnabled = true;
1553 }
1554
1555 void ItemView::SetOvershootEffectColor( const Vector4& color )
1556 {
1557   mOvershootEffectColor = color;
1558   if( mOvershootOverlay )
1559   {
1560     mOvershootOverlay.SetColor( color );
1561   }
1562 }
1563
1564 void ItemView::SetOvershootEnabled( bool enable )
1565 {
1566   Actor self = Self();
1567   if( enable )
1568   {
1569     Property::Index effectOvershootPropertyIndex = Property::INVALID_INDEX;
1570     mOvershootOverlay = CreateBouncingEffectActor( effectOvershootPropertyIndex );
1571     mOvershootOverlay.SetColor(mOvershootEffectColor);
1572     mOvershootOverlay.SetParentOrigin(ParentOrigin::TOP_LEFT);
1573     mOvershootOverlay.SetAnchorPoint(AnchorPoint::TOP_LEFT);
1574     mOvershootOverlay.SetDrawMode(DrawMode::OVERLAY);
1575     self.Add(mOvershootOverlay);
1576
1577     Constraint constraint = Constraint::New<Vector3>( Actor::SIZE,
1578                                                       ParentSource( mPropertyScrollDirection ),
1579                                                       Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1580                                                       ParentSource( Actor::SIZE ),
1581                                                       OvershootOverlaySizeConstraint() );
1582     mOvershootOverlay.ApplyConstraint(constraint);
1583     mOvershootOverlay.SetSize(OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.width, OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height);
1584
1585     constraint = Constraint::New<Quaternion>( Actor::ROTATION,
1586                                               ParentSource( mPropertyScrollDirection ),
1587                                               Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1588                                               OvershootOverlayRotationConstraint() );
1589     mOvershootOverlay.ApplyConstraint(constraint);
1590
1591     constraint = Constraint::New<Vector3>( Actor::POSITION,
1592                                            ParentSource( Actor::SIZE ),
1593                                            ParentSource( mPropertyScrollDirection ),
1594                                            Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1595                                            OvershootOverlayPositionConstraint() );
1596     mOvershootOverlay.ApplyConstraint(constraint);
1597
1598     constraint = Constraint::New<bool>( Actor::VISIBLE,
1599                                         ParentSource( mPropertyCanScrollVertical ),
1600                                         OvershootOverlayVisibilityConstraint() );
1601     mOvershootOverlay.ApplyConstraint(constraint);
1602
1603     Actor self = Self();
1604     constraint = Constraint::New<float>( effectOvershootPropertyIndex,
1605                                          Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1606                                          EqualToConstraint() );
1607     mOvershootOverlay.ApplyConstraint(constraint);
1608   }
1609   else
1610   {
1611     if( mOvershootOverlay )
1612     {
1613       self.Remove(mOvershootOverlay);
1614       mOvershootOverlay.Reset();
1615     }
1616   }
1617 }
1618
1619 float ItemView::CalculateScrollOvershoot()
1620 {
1621   float overshoot = 0.0f;
1622
1623   if(mActiveLayout)
1624   {
1625     // The overshoot must be calculated from the accumulated pan gesture displacement
1626     // since the pan gesture starts.
1627     Actor self = Self();
1628     float scrollDistance = CalculateScrollDistance(mTotalPanDisplacement, *mActiveLayout) * mActiveLayout->GetScrollSpeedFactor();
1629     float positionDelta = GetCurrentLayoutPosition(0) + scrollDistance;
1630     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), Self().GetCurrentSize());
1631     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1632     float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, positionDelta));
1633     overshoot = positionDelta - clamppedPosition;
1634   }
1635
1636   return overshoot;
1637 }
1638
1639 void ItemView::AnimateScrollOvershoot(float overshootAmount, bool animateBack)
1640 {
1641   bool animatingOn = fabsf(overshootAmount) > Math::MACHINE_EPSILON_1;
1642
1643   // make sure we animate back if needed
1644   mAnimateOvershootOff = animateBack || (!animatingOn && mAnimatingOvershootOn);
1645
1646   if( mAnimatingOvershootOn )
1647   {
1648     // animating on, do not allow animate off
1649     return;
1650   }
1651
1652   Actor self = Self();
1653   float currentOvershoot = mScrollPositionObject.GetProperty<float>(ScrollConnector::OVERSHOOT);
1654   float duration = DEFAULT_OVERSHOOT_ANIMATION_DURATION * (animatingOn ? (1.0f - fabsf(currentOvershoot)) : fabsf(currentOvershoot));
1655
1656   RemoveAnimation(mScrollOvershootAnimation);
1657   mScrollOvershootAnimation = Animation::New(duration);
1658   mScrollOvershootAnimation.FinishedSignal().Connect(this, &ItemView::OnOvershootOnFinished);
1659   mScrollOvershootAnimation.AnimateTo( Property(mScrollPositionObject, ScrollConnector::OVERSHOOT), overshootAmount, TimePeriod(0.0f, duration) );
1660   mScrollOvershootAnimation.Play();
1661
1662   mAnimatingOvershootOn = animatingOn;
1663 }
1664
1665 void ItemView::SetItemsParentOrigin( const Vector3& parentOrigin )
1666 {
1667   if( parentOrigin != mItemsParentOrigin )
1668   {
1669     mItemsParentOrigin = parentOrigin;
1670     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1671     {
1672       iter->second.SetParentOrigin(parentOrigin);
1673     }
1674   }
1675 }
1676
1677 Vector3 ItemView::GetItemsParentOrigin() const
1678 {
1679   return mItemsParentOrigin;
1680 }
1681
1682 void ItemView::SetItemsAnchorPoint( const Vector3& anchorPoint )
1683 {
1684   if( anchorPoint != mItemsAnchorPoint )
1685   {
1686     mItemsAnchorPoint = anchorPoint;
1687     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1688     {
1689       iter->second.SetAnchorPoint(anchorPoint);
1690     }
1691   }
1692 }
1693
1694 Vector3 ItemView::GetItemsAnchorPoint() const
1695 {
1696   return mItemsAnchorPoint;
1697 }
1698
1699 void ItemView::GetItemsRange(ItemRange& range)
1700 {
1701   if( !mItemPool.empty() )
1702   {
1703     range.begin = mItemPool.begin()->first;
1704     range.end = mItemPool.rbegin()->first + 1;
1705   }
1706   else
1707   {
1708     range.begin = 0;
1709     range.end = 0;
1710   }
1711 }
1712
1713 void ItemView::OnScrollPositionChanged( float position )
1714 {
1715   // Cancel scroll animation to prevent any fighting of setting the scroll position property.
1716   RemoveAnimation(mScrollAnimation);
1717
1718   // Refresh the cache immediately when the scroll position is changed.
1719   DoRefresh(position, false); // No need to cache extra items.
1720 }
1721
1722 } // namespace Internal
1723
1724 } // namespace Toolkit
1725
1726 } // namespace Dali