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   mScrollDistance(0.0f),
 341   mScrollSpeed(0.0f),
 342   mTotalPanDisplacement(Vector2::ZERO),
 343   mScrollOvershoot(0.0f),
 344   mIsFlicking(false),
 345   mGestureState(Gesture::Clear),
 346   mAddingItems(false),
 347   mRefreshEnabled(true),
 348   mItemsParentOrigin( ParentOrigin::CENTER),
 349   mItemsAnchorPoint( AnchorPoint::CENTER)
 350 {
 351   SetRequiresMouseWheelEvents(true);
 352   SetKeyboardNavigationSupport(true);
 353 }
 354
 355 void ItemView::OnInitialize()
 356 {
 357   SetSizePolicy( Toolkit::Control::Fixed, Toolkit::Control::Fixed );
 358
 359   RegisterCommonProperties();
 360
 361   Actor self = Self();
 362
 363   mScrollConnector = Dali::Toolkit::ScrollConnector::New();
 364   mScrollPositionObject = mScrollConnector.GetScrollPositionObject();
 365   mScrollConnector.ScrollPositionChangedSignal().Connect( this, &ItemView::OnScrollPositionChanged );
 366
 367   mPropertyMinimumLayoutPosition = self.RegisterProperty(MINIMUM_LAYOUT_POSITION_PROPERTY_NAME, 0.0f);
 368   mPropertyPosition = self.RegisterProperty(POSITION_PROPERTY_NAME, 0.0f);
 369   mPropertyScrollSpeed = self.RegisterProperty(SCROLL_SPEED_PROPERTY_NAME, 0.0f);
 370
 371   EnableScrollComponent(Toolkit::Scrollable::OvershootIndicator);
 372
 373   Constraint constraint = Constraint::New<Vector3>(mPropertyRelativePosition,
 374                                                    LocalSource(mPropertyPosition),
 375                                                    LocalSource(mPropertyPositionMin),
 376                                                    LocalSource(mPropertyPositionMax),
 377                                                    LocalSource(Actor::SIZE),
 378                                                    RelativePositionConstraint);
 379   self.ApplyConstraint(constraint);
 380
 381   Vector2 stageSize = Stage::GetCurrent().GetSize();
 382   mMouseWheelScrollDistanceStep = stageSize.y * DEFAULT_MOUSE_WHEEL_SCROLL_DISTANCE_STEP_PROPORTION;
 383
 384   EnableGestureDetection(Gesture::Type(Gesture::Pan));
 385
 386   mMouseWheelEventFinishedTimer = Timer::New( MOUSE_WHEEL_EVENT_FINISHED_TIME_OUT );
 387   mMouseWheelEventFinishedTimer.TickSignal().Connect( this, &ItemView::OnMouseWheelEventFinished );
 388
 389   SetRefreshInterval(DEFAULT_REFRESH_INTERVAL_LAYOUT_POSITIONS);
 390 }
 391
 392 ItemView::~ItemView()
 393 {
 394 }
 395
 396 Dali::Toolkit::ScrollConnector ItemView::GetScrollConnector() const
 397 {
 398   return mScrollConnector;
 399 }
 400
 401 unsigned int ItemView::GetLayoutCount() const
 402 {
 403   return mLayouts.size();
 404 }
 405
 406 void ItemView::AddLayout(ItemLayout& layout)
 407 {
 408   mLayouts.push_back(ItemLayoutPtr(&layout));
 409 }
 410
 411 void ItemView::RemoveLayout(unsigned int layoutIndex)
 412 {
 413   DALI_ASSERT_ALWAYS(layoutIndex < mLayouts.size());
 414
 415   if (mActiveLayout == mLayouts[layoutIndex].Get())
 416   {
 417     mActiveLayout = NULL;
 418   }
 419
 420   mLayouts.erase(mLayouts.begin() + layoutIndex);
 421 }
 422
 423 ItemLayoutPtr ItemView::GetLayout(unsigned int layoutIndex) const
 424 {
 425   return mLayouts[layoutIndex];
 426 }
 427
 428 ItemLayoutPtr ItemView::GetActiveLayout() const
 429 {
 430   return ItemLayoutPtr(mActiveLayout);
 431 }
 432
 433 float ItemView::GetCurrentLayoutPosition(unsigned int itemId) const
 434 {
 435   return mScrollConnector.GetScrollPosition() + static_cast<float>( itemId );
 436 }
 437
 438 void ItemView::ActivateLayout(unsigned int layoutIndex, const Vector3& targetSize, float durationSeconds)
 439 {
 440   DALI_ASSERT_ALWAYS(layoutIndex < mLayouts.size());
 441
 442   mRefreshEnabled = false;
 443
 444   Actor self = Self();
 445
 446   // The ItemView size should match the active layout size
 447   self.SetSize(targetSize);
 448   mActiveLayoutTargetSize = targetSize;
 449
 450   // Switch to the new layout
 451   mActiveLayout = mLayouts[layoutIndex].Get();
 452
 453   // Move the items to the new layout positions...
 454
 455   bool resizeAnimationNeeded(false);
 456   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 457   {
 458     unsigned int itemId = iter->first;
 459     Actor actor = iter->second;
 460
 461     // Remove constraints from previous layout
 462     actor.RemoveConstraints();
 463
 464     Vector3 size;
 465     if(mActiveLayout->GetItemSize(itemId, targetSize, size))
 466     {
 467       if( durationSeconds > 0.0f )
 468       {
 469         // Use a size animation
 470         if (!resizeAnimationNeeded)
 471         {
 472           resizeAnimationNeeded = true;
 473           RemoveAnimation(mResizeAnimation);
 474           mResizeAnimation = Animation::New(durationSeconds);
 475         }
 476
 477         // The layout provides its own resize animation
 478         mActiveLayout->GetResizeAnimation(mResizeAnimation, actor, size, durationSeconds);
 479       }
 480       else
 481       {
 482         // resize immediately
 483         actor.SetSize(size);
 484       }
 485     }
 486
 487     mActiveLayout->ApplyConstraints(actor, itemId, durationSeconds, mScrollPositionObject, Self() );
 488   }
 489
 490   if (resizeAnimationNeeded)
 491   {
 492     mResizeAnimation.Play();
 493   }
 494
 495   // Refresh the new layout
 496   ItemRange range = GetItemRange(*mActiveLayout, targetSize, GetCurrentLayoutPosition(0), false/* don't reserve extra*/);
 497   AddActorsWithinRange( range, durationSeconds );
 498
 499   // Scroll to an appropriate layout position
 500
 501   bool scrollAnimationNeeded(false);
 502   float firstItemScrollPosition(0.0f);
 503
 504   float current = GetCurrentLayoutPosition(0);
 505   float minimum = ClampFirstItemPosition(current, targetSize, *mActiveLayout);
 506   self.SetProperty(mPropertyPosition, GetScrollPosition(current, targetSize));
 507
 508   if (current < minimum)
 509   {
 510     scrollAnimationNeeded = true;
 511     firstItemScrollPosition = minimum;
 512   }
 513   else if (mAnchoringEnabled)
 514   {
 515     scrollAnimationNeeded = true;
 516     firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(current);
 517   }
 518
 519   if (scrollAnimationNeeded)
 520   {
 521     RemoveAnimation(mScrollAnimation);
 522     mScrollAnimation = Animation::New(durationSeconds);
 523     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
 524     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, targetSize), AlphaFunctions::EaseOut );
 525     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnLayoutActivationScrollFinished);
 526     mScrollAnimation.Play();
 527   }
 528
 529   self.SetProperty(mPropertyMinimumLayoutPosition, mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize));
 530   AnimateScrollOvershoot(0.0f);
 531   mScrollOvershoot = 0.0f;
 532
 533   Radian scrollDirection(mActiveLayout->GetScrollDirection());
 534   float orientation = static_cast<float>(mActiveLayout->GetOrientation());
 535   self.SetProperty(mPropertyScrollDirection, Vector3(sinf(scrollDirection), cosf(scrollDirection), orientation));
 536
 537   self.SetProperty(mPropertyScrollSpeed, mScrollSpeed);
 538
 539   CalculateDomainSize(targetSize);
 540 }
 541
 542 void ItemView::DeactivateCurrentLayout()
 543 {
 544   if (mActiveLayout)
 545   {
 546     for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 547     {
 548       Actor actor = iter->second;
 549       actor.RemoveConstraints();
 550     }
 551
 552     mActiveLayout = NULL;
 553   }
 554 }
 555
 556 void ItemView::OnRefreshNotification(PropertyNotification& source)
 557 {
 558   if(mRefreshEnabled || mScrollAnimation)
 559   {
 560     // Only refresh the cache during normal scrolling
 561     DoRefresh(GetCurrentLayoutPosition(0), true);
 562   }
 563 }
 564
 565 void ItemView::DoRefresh(float currentLayoutPosition, bool cacheExtra)
 566 {
 567   if (mActiveLayout)
 568   {
 569     ItemRange range = GetItemRange(*mActiveLayout, mActiveLayoutTargetSize, currentLayoutPosition, cacheExtra/*reserve extra*/);
 570     RemoveActorsOutsideRange( range );
 571     AddActorsWithinRange( range, 0.0f/*immediate*/ );
 572
 573     mScrollUpdatedSignalV2.Emit( Vector3(0.0f, currentLayoutPosition, 0.0f) );
 574   }
 575 }
 576
 577 void ItemView::SetMinimumSwipeSpeed(float speed)
 578 {
 579   mMinimumSwipeSpeed = speed;
 580 }
 581
 582 float ItemView::GetMinimumSwipeSpeed() const
 583 {
 584   return mMinimumSwipeSpeed;
 585 }
 586
 587 void ItemView::SetMinimumSwipeDistance(float distance)
 588 {
 589   mMinimumSwipeDistance = distance;
 590 }
 591
 592 float ItemView::GetMinimumSwipeDistance() const
 593 {
 594   return mMinimumSwipeDistance;
 595 }
 596
 597 void ItemView::SetMouseWheelScrollDistanceStep(float step)
 598 {
 599   mMouseWheelScrollDistanceStep = step;
 600 }
 601
 602 float ItemView::GetMouseWheelScrollDistanceStep() const
 603 {
 604   return mMouseWheelScrollDistanceStep;
 605 }
 606
 607 void ItemView::SetAnchoring(bool enabled)
 608 {
 609   mAnchoringEnabled = enabled;
 610 }
 611
 612 bool ItemView::GetAnchoring() const
 613 {
 614   return mAnchoringEnabled;
 615 }
 616
 617 void ItemView::SetAnchoringDuration(float durationSeconds)
 618 {
 619   mAnchoringDuration = durationSeconds;
 620 }
 621
 622 float ItemView::GetAnchoringDuration() const
 623 {
 624   return mAnchoringDuration;
 625 }
 626
 627 void ItemView::SetRefreshInterval(float intervalLayoutPositions)
 628 {
 629   if(mRefreshIntervalLayoutPositions != intervalLayoutPositions)
 630   {
 631     mRefreshIntervalLayoutPositions = intervalLayoutPositions;
 632
 633     if(mRefreshNotification)
 634     {
 635       mScrollPositionObject.RemovePropertyNotification(mRefreshNotification);
 636     }
 637     mRefreshNotification = mScrollPositionObject.AddPropertyNotification( ScrollConnector::SCROLL_POSITION, StepCondition(mRefreshIntervalLayoutPositions, 0.0f) );
 638     mRefreshNotification.NotifySignal().Connect( this, &ItemView::OnRefreshNotification );
 639   }
 640 }
 641
 642 float ItemView::GetRefreshInterval() const
 643 {
 644   return mRefreshIntervalLayoutPositions;
 645 }
 646
 647 void ItemView::SetRefreshEnabled(bool enabled)
 648 {
 649   mRefreshEnabled = enabled;
 650 }
 651
 652 Actor ItemView::GetItem(unsigned int itemId) const
 653 {
 654   Actor actor;
 655
 656   ConstItemPoolIter iter = mItemPool.find( itemId );
 657   if( iter != mItemPool.end() )
 658   {
 659     actor = iter->second;
 660   }
 661
 662   return actor;
 663 }
 664
 665 unsigned int ItemView::GetItemId( Actor actor ) const
 666 {
 667   unsigned int itemId( 0 );
 668
 669   for ( ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter )
 670   {
 671     if( iter->second == actor )
 672     {
 673       itemId = iter->first;
 674       break;
 675     }
 676   }
 677
 678   return itemId;
 679 }
 680
 681 void ItemView::InsertItem( Item newItem, float durationSeconds )
 682 {
 683   mAddingItems = true;
 684
 685   SetupActor( newItem, durationSeconds );
 686   Self().Add( newItem.second );
 687
 688   ItemPoolIter foundIter = mItemPool.find( newItem.first );
 689   if( mItemPool.end() != foundIter )
 690   {
 691     Actor moveMe = foundIter->second;
 692     foundIter->second = newItem.second;
 693
 694     // Move the existing actors to make room
 695     for( ItemPoolIter iter = ++foundIter; mItemPool.end() != iter; ++iter )
 696     {
 697       Actor temp = iter->second;
 698       iter->second = moveMe;
 699       moveMe = temp;
 700
 701       iter->second.RemoveConstraints();
 702       mActiveLayout->ApplyConstraints(iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 703     }
 704
 705     // Create last item
 706     ItemId lastId = mItemPool.rbegin()->first;
 707     Item lastItem( lastId + 1, moveMe );
 708     mItemPool.insert( lastItem );
 709
 710     lastItem.second.RemoveConstraints();
 711     mActiveLayout->ApplyConstraints(lastItem.second, lastItem.first, durationSeconds, mScrollPositionObject, Self() );
 712   }
 713   else
 714   {
 715     mItemPool.insert( newItem );
 716   }
 717
 718   CalculateDomainSize(Self().GetCurrentSize());
 719
 720   mAddingItems = false;
 721 }
 722
 723 void ItemView::InsertItems( const ItemContainer& newItems, float durationSeconds )
 724 {
 725   mAddingItems = true;
 726
 727   // Insert from lowest id to highest
 728   std::set<Item> sortedItems;
 729   for( ConstItemIter iter = newItems.begin(); newItems.end() != iter; ++iter )
 730   {
 731     sortedItems.insert( *iter );
 732   }
 733
 734   for( std::set<Item>::iterator iter = sortedItems.begin(); sortedItems.end() != iter; ++iter )
 735   {
 736     Self().Add( iter->second );
 737
 738     ItemPoolIter foundIter = mItemPool.find( iter->first );
 739     if( mItemPool.end() != foundIter )
 740     {
 741       Actor moveMe = foundIter->second;
 742       foundIter->second = iter->second;
 743
 744       // Move the existing actors to make room
 745       for( ItemPoolIter iter = ++foundIter; mItemPool.end() != iter; ++iter )
 746       {
 747         Actor temp = iter->second;
 748         iter->second = moveMe;
 749         moveMe = temp;
 750       }
 751
 752       // Create last item
 753       ItemId lastId = mItemPool.rbegin()->first;
 754       Item lastItem( lastId + 1, moveMe );
 755       mItemPool.insert( lastItem );
 756     }
 757     else
 758     {
 759       mItemPool.insert( *iter );
 760     }
 761   }
 762
 763   // Relayout everything
 764   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
 765   {
 766     // If newly inserted
 767     if( FindById( newItems, iter->first ) )
 768     {
 769       SetupActor( *iter, durationSeconds );
 770     }
 771     else
 772     {
 773       iter->second.RemoveConstraints();
 774       mActiveLayout->ApplyConstraints( iter->second, iter->first, durationSeconds, mScrollPositionObject, Self() );
 775     }
 776   }
 777
 778   CalculateDomainSize(Self().GetCurrentSize());
 779
 780   mAddingItems = false;
 781 }
 782
 783 void ItemView::RemoveItem( unsigned int itemId, float durationSeconds )
 784 {
 785   bool actorRemoved = RemoveActor( itemId );
 786   if( actorRemoved )
 787   {
 788     ReapplyAllConstraints( durationSeconds );
 789   }
 790 }
 791
 792 void ItemView::RemoveItems( const ItemIdContainer& itemIds, float durationSeconds )
 793 {
 794   bool actorRemoved( false );
 795
 796   // Remove from highest id to lowest
 797   set<ItemId> sortedItems;
 798   for( ConstItemIdIter iter = itemIds.begin(); itemIds.end() != iter; ++iter )
 799   {
 800     sortedItems.insert( *iter );
 801   }
 802
 803   for( set<ItemId>::reverse_iterator iter = sortedItems.rbegin(); sortedItems.rend() != iter; ++iter )
 804   {
 805     if( RemoveActor( *iter ) )
 806     {
 807       actorRemoved = true;
 808     }
 809   }
 810
 811   if( actorRemoved )
 812   {
 813     ReapplyAllConstraints( durationSeconds );
 814   }
 815 }
 816
 817 bool ItemView::RemoveActor(unsigned int itemId)
 818 {
 819   bool removed( false );
 820
 821   const ItemPoolIter removeIter = mItemPool.find( itemId );
 822
 823   if( removeIter != mItemPool.end() )
 824   {
 825     ReleaseActor(itemId, removeIter->second);
 826
 827     removed = true;
 828
 829     // Adjust the remaining item IDs, for example if item 2 is removed:
 830     //   Initial actors:     After insert:
 831     //     ID 1 - ActorA       ID 1 - ActorA
 832     //     ID 2 - ActorB       ID 2 - ActorC (previously ID 3)
 833     //     ID 3 - ActorC       ID 3 - ActorB (previously ID 4)
 834     //     ID 4 - ActorD
 835     for (ItemPoolIter iter = removeIter; iter != mItemPool.end(); ++iter)
 836     {
 837       if( iter->first < mItemPool.rbegin()->first )
 838       {
 839         iter->second = mItemPool[ iter->first + 1 ];
 840       }
 841       else
 842       {
 843         mItemPool.erase( iter );
 844         break;
 845       }
 846     }
 847   }
 848
 849   return removed;
 850 }
 851
 852 void ItemView::ReplaceItem( Item replacementItem, float durationSeconds )
 853 {
 854   mAddingItems = true;
 855
 856   SetupActor( replacementItem, durationSeconds );
 857   Self().Add( replacementItem.second );
 858
 859   const ItemPoolIter iter = mItemPool.find( replacementItem.first );
 860   if( mItemPool.end() != iter )
 861   {
 862     ReleaseActor(iter->first, iter->second);
 863     iter->second = replacementItem.second;
 864   }
 865   else
 866   {
 867     mItemPool.insert( replacementItem );
 868   }
 869
 870   CalculateDomainSize(Self().GetCurrentSize());
 871
 872   mAddingItems = false;
 873 }
 874
 875 void ItemView::ReplaceItems( const ItemContainer& replacementItems, float durationSeconds )
 876 {
 877   for( ConstItemIter iter = replacementItems.begin(); replacementItems.end() != iter; ++iter )
 878   {
 879     ReplaceItem( *iter, durationSeconds );
 880   }
 881 }
 882
 883 void ItemView::RemoveActorsOutsideRange( ItemRange range )
 884 {
 885   // Remove unwanted actors from the ItemView & ItemPool
 886   for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); )
 887   {
 888     unsigned int current = iter->first;
 889
 890     if( ! range.Within( current ) )
 891     {
 892       ReleaseActor(iter->first, iter->second);
 893
 894       mItemPool.erase( iter++ ); // erase invalidates the return value of post-increment; iter remains valid
 895     }
 896     else
 897     {
 898       ++iter;
 899     }
 900   }
 901 }
 902
 903 void ItemView::AddActorsWithinRange( ItemRange range, float durationSeconds )
 904 {
 905   range.end = std::min(mItemFactory.GetNumberOfItems(), range.end);
 906
 907   // The order of addition depends on the scroll direction.
 908   if (mRefreshOrderHint)
 909   {
 910     for (unsigned int itemId = range.begin; itemId < range.end; ++itemId)
 911     {
 912       AddNewActor( itemId, durationSeconds );
 913     }
 914   }
 915   else
 916   {
 917     for (unsigned int itemId = range.end; itemId > range.begin; --itemId)
 918     {
 919       AddNewActor( itemId-1, durationSeconds );
 920     }
 921   }
 922
 923   // Total number of items may change dynamically.
 924   // Always recalculate the domain size to reflect that.
 925   CalculateDomainSize(Self().GetCurrentSize());
 926 }
 927
 928 void ItemView::AddNewActor( unsigned int itemId, float durationSeconds )
 929 {
 930   mAddingItems = true;
 931
 932   if( mItemPool.end() == mItemPool.find( itemId ) )
 933   {
 934     Actor actor = mItemFactory.NewItem( itemId );
 935
 936     if( actor )
 937     {
 938       Item newItem( itemId, actor );
 939
 940       mItemPool.insert( newItem );
 941
 942       SetupActor( newItem, durationSeconds );
 943       Self().Add( actor );
 944     }
 945   }
 946
 947   mAddingItems = false;
 948 }
 949
 950 void ItemView::SetupActor( Item item, float durationSeconds )
 951 {
 952   item.second.SetParentOrigin( mItemsParentOrigin );
 953   item.second.SetAnchorPoint( mItemsAnchorPoint );
 954
 955   if( mActiveLayout )
 956   {
 957     Vector3 size;
 958     if( mActiveLayout->GetItemSize( item.first, mActiveLayoutTargetSize, size ) )
 959     {
 960       item.second.SetSize( size );
 961     }
 962
 963     mActiveLayout->ApplyConstraints( item.second, item.first, durationSeconds, mScrollPositionObject, Self() );
 964   }
 965 }
 966
 967 void ItemView::ReleaseActor( ItemId item, Actor actor )
 968 {
 969   Self().Remove( actor );
 970   mItemFactory.ItemReleased(item, actor);
 971 }
 972
 973 ItemRange ItemView::GetItemRange(ItemLayout& layout, const Vector3& layoutSize, float layoutPosition, bool reserveExtra)
 974 {
 975   unsigned int itemCount = mItemFactory.GetNumberOfItems();
 976
 977   ItemRange available(0u, itemCount);
 978
 979   ItemRange range = layout.GetItemsWithinArea( layoutPosition, layoutSize );
 980
 981   if (reserveExtra)
 982   {
 983     // Add the reserve items for scrolling
 984     unsigned int extra = layout.GetReserveItemCount(layoutSize);
 985     range.begin = (range.begin >= extra) ? (range.begin - extra) : 0u;
 986     range.end += extra;
 987   }
 988
 989   return range.Intersection(available);
 990 }
 991
 992 void ItemView::OnChildAdd(Actor& child)
 993 {
 994   if(!mAddingItems)
 995   {
 996     // We don't want to do this downcast check for any item added by ItemView itself.
 997     Dali::Toolkit::ScrollComponent scrollComponent = Dali::Toolkit::ScrollComponent::DownCast(child);
 998     if(scrollComponent)
 999     {
1000       // Set the scroll connector when scroll bar is being added
1001       scrollComponent.SetScrollConnector(mScrollConnector);
1002     }
1003   }
1004 }
1005
1006 bool ItemView::OnTouchEvent(const TouchEvent& event)
1007 {
1008   // Ignore events with multiple-touch points
1009   if (event.GetPointCount() != 1)
1010   {
1011     return false;
1012   }
1013
1014   if (event.GetPoint(0).state == TouchPoint::Down)
1015   {
1016     // Cancel ongoing scrolling etc.
1017     mGestureState = Gesture::Clear;
1018
1019     mScrollDistance = 0.0f;
1020     mScrollSpeed = 0.0f;
1021     Self().SetProperty(mPropertyScrollSpeed, mScrollSpeed);
1022
1023     mScrollOvershoot = 0.0f;
1024     AnimateScrollOvershoot(0.0f);
1025
1026     if(mScrollAnimation)
1027     {
1028       mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1029     }
1030
1031     RemoveAnimation(mScrollAnimation);
1032   }
1033
1034   return true; // consume since we're potentially scrolling
1035 }
1036
1037 bool ItemView::OnMouseWheelEvent(const MouseWheelEvent& event)
1038 {
1039   // Respond the mouse wheel event to scroll
1040   if (mActiveLayout)
1041   {
1042     Actor self = Self();
1043     const Vector3 layoutSize = Self().GetCurrentSize();
1044     float layoutPositionDelta = GetCurrentLayoutPosition(0) - (event.z * mMouseWheelScrollDistanceStep * mActiveLayout->GetScrollSpeedFactor());
1045     float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1046
1047     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1048     self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1049     mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1050     mRefreshEnabled = true;
1051   }
1052
1053   if (mMouseWheelEventFinishedTimer.IsRunning())
1054   {
1055     mMouseWheelEventFinishedTimer.Stop();
1056   }
1057
1058   mMouseWheelEventFinishedTimer.Start();
1059
1060   return true;
1061 }
1062
1063 bool ItemView::OnMouseWheelEventFinished()
1064 {
1065   if (mActiveLayout)
1066   {
1067     RemoveAnimation(mScrollAnimation);
1068
1069     // No more mouse wheel events coming. Do the anchoring if enabled.
1070     mScrollAnimation = DoAnchoring();
1071     if (mScrollAnimation)
1072     {
1073       mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1074       mScrollAnimation.Play();
1075     }
1076     else
1077     {
1078       mScrollOvershoot = 0.0f;
1079       AnimateScrollOvershoot(0.0f);
1080
1081       mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1082     }
1083   }
1084
1085   return false;
1086 }
1087
1088 void ItemView::ReapplyAllConstraints( float durationSeconds )
1089 {
1090   for (ConstItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1091   {
1092     unsigned int id = iter->first;
1093     Actor actor = iter->second;
1094
1095     actor.RemoveConstraints();
1096     mActiveLayout->ApplyConstraints(actor, id, durationSeconds, mScrollPositionObject, Self());
1097   }
1098
1099   CalculateDomainSize(Self().GetCurrentSize());
1100 }
1101
1102 float ItemView::ClampFirstItemPosition(float targetPosition, const Vector3& targetSize, ItemLayout& layout)
1103 {
1104   Actor self = Self();
1105   float minLayoutPosition = layout.GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), targetSize);
1106   float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, targetPosition));
1107   mScrollOvershoot = targetPosition - clamppedPosition;
1108   self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1109
1110   return clamppedPosition;
1111 }
1112
1113 void ItemView::OnPan(PanGesture gesture)
1114 {
1115   Actor self = Self();
1116   const Vector3 layoutSize = Self().GetCurrentSize();
1117
1118   RemoveAnimation(mScrollAnimation);
1119
1120   // Short-circuit if there is no active layout
1121   if (!mActiveLayout)
1122   {
1123     mGestureState = Gesture::Clear;
1124     return;
1125   }
1126
1127   mGestureState = gesture.state;
1128
1129   switch (mGestureState)
1130   {
1131     case Gesture::Finished:
1132     {
1133       // Swipe Detection
1134       if (fabsf(mScrollDistance) > mMinimumSwipeDistance &&
1135           mScrollSpeed > mMinimumSwipeSpeed)
1136       {
1137         float direction = (mScrollDistance < 0.0f) ? -1.0f : 1.0f;
1138
1139         mRefreshOrderHint = true;
1140
1141         float currentLayoutPosition = GetCurrentLayoutPosition(0);
1142         float firstItemScrollPosition = ClampFirstItemPosition(currentLayoutPosition + mScrollSpeed * direction,
1143                                                                layoutSize,
1144                                                                *mActiveLayout);
1145
1146         if (mAnchoringEnabled)
1147         {
1148           firstItemScrollPosition = mActiveLayout->GetClosestAnchorPosition(firstItemScrollPosition);
1149         }
1150
1151         RemoveAnimation(mScrollAnimation);
1152
1153         float flickAnimationDuration = Clamp( mActiveLayout->GetItemFlickAnimationDuration() * std::max(1.0f, fabsf(firstItemScrollPosition - GetCurrentLayoutPosition(0)))
1154                                        , DEFAULT_MINIMUM_SWIPE_DURATION, DEFAULT_MAXIMUM_SWIPE_DURATION);
1155
1156         mScrollAnimation = Animation::New(flickAnimationDuration);
1157         mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1158         mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1159         mScrollAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1160
1161         mIsFlicking = true;
1162         // Check whether it has already scrolled to the end
1163         if(fabs(currentLayoutPosition - firstItemScrollPosition) > Math::MACHINE_EPSILON_0)
1164         {
1165           AnimateScrollOvershoot(0.0f);
1166         }
1167       }
1168
1169       // Anchoring may be triggered when there was no swipe
1170       if (!mScrollAnimation)
1171       {
1172         mScrollAnimation = DoAnchoring();
1173       }
1174
1175       // Reset the overshoot if no scroll animation.
1176       if (!mScrollAnimation)
1177       {
1178         mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1179
1180         AnimateScrollOvershoot(0.0f, false);
1181       }
1182     }
1183     break;
1184
1185     case Gesture::Started: // Fall through
1186     {
1187       mTotalPanDisplacement = Vector2::ZERO;
1188       mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1189       mRefreshEnabled = true;
1190     }
1191
1192     case Gesture::Continuing:
1193     {
1194       mScrollDistance = CalculateScrollDistance(gesture.displacement, *mActiveLayout);
1195       mScrollSpeed = Clamp((gesture.GetSpeed() * gesture.GetSpeed() * mActiveLayout->GetFlickSpeedFactor() * MILLISECONDS_PER_SECONDS), 0.0f, mActiveLayout->GetMaximumSwipeSpeed());
1196
1197       // Refresh order depends on the direction of the scroll; negative is towards the last item.
1198       mRefreshOrderHint = mScrollDistance < 0.0f;
1199
1200       float layoutPositionDelta = GetCurrentLayoutPosition(0) + (mScrollDistance * mActiveLayout->GetScrollSpeedFactor());
1201
1202       float firstItemScrollPosition = ClampFirstItemPosition(layoutPositionDelta, layoutSize, *mActiveLayout);
1203
1204       mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1205       self.SetProperty(mPropertyPosition, GetScrollPosition(firstItemScrollPosition, layoutSize));
1206
1207       mTotalPanDisplacement += gesture.displacement;
1208       mScrollOvershoot = layoutPositionDelta - firstItemScrollPosition;
1209       if( mScrollOvershoot > Math::MACHINE_EPSILON_1 )
1210       {
1211         AnimateScrollOvershoot(1.0f);
1212       }
1213       else if( mScrollOvershoot < -Math::MACHINE_EPSILON_1 )
1214       {
1215         AnimateScrollOvershoot(-1.0f);
1216       }
1217       else
1218       {
1219         AnimateScrollOvershoot(0.0f);
1220       }
1221     }
1222     break;
1223
1224     case Gesture::Cancelled:
1225     {
1226       mScrollAnimation = DoAnchoring();
1227     }
1228     break;
1229
1230     default:
1231       break;
1232   }
1233
1234   if (mScrollAnimation)
1235   {
1236     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1237     mScrollAnimation.Play();
1238   }
1239 }
1240
1241 bool ItemView::OnAccessibilityPan(PanGesture gesture)
1242 {
1243   OnPan(gesture);
1244   return true;
1245 }
1246
1247 Actor ItemView::GetNextKeyboardFocusableActor(Actor actor, Toolkit::Control::KeyboardFocusNavigationDirection direction, bool loopEnabled)
1248 {
1249   Actor nextFocusActor;
1250   if(mActiveLayout)
1251   {
1252     int nextItemID = 0;
1253     if(!actor || actor == this->Self())
1254     {
1255       nextFocusActor = GetItem(nextItemID);
1256     }
1257     else if(actor && actor.GetParent() == this->Self())
1258     {
1259       int itemID = GetItemId(actor);
1260       nextItemID = mActiveLayout->GetNextFocusItemID(itemID, mItemFactory.GetNumberOfItems(), direction, loopEnabled);
1261       nextFocusActor = GetItem(nextItemID);
1262       if(nextFocusActor == actor)
1263       {
1264         // need to pass NULL actor back to focus manager
1265         nextFocusActor.Reset();
1266         return nextFocusActor;
1267       }
1268     }
1269     float layoutPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1270     Vector3 layoutSize = Self().GetCurrentSize();
1271     if(!nextFocusActor)
1272     {
1273       // likely the current item is not buffered, so not in our item pool, probably best to get first viewable item
1274       ItemRange viewableItems = mActiveLayout->GetItemsWithinArea(layoutPosition, layoutSize);
1275       nextItemID = viewableItems.begin;
1276       nextFocusActor = GetItem(nextItemID);
1277     }
1278   }
1279   return nextFocusActor;
1280 }
1281
1282 void ItemView::OnKeyboardFocusChangeCommitted(Actor commitedFocusableActor)
1283 {
1284   // only in this function if our chosen focus actor was actually used
1285   if(commitedFocusableActor)
1286   {
1287     int nextItemID = GetItemId(commitedFocusableActor);
1288     float layoutPosition = GetCurrentLayoutPosition(0);
1289     Vector3 layoutSize = Self().GetCurrentSize();
1290
1291     float scrollTo = mActiveLayout->GetClosestOnScreenLayoutPosition(nextItemID, layoutPosition, layoutSize);
1292     ScrollTo(Vector3(0.0f, scrollTo, 0.0f), DEFAULT_KEYBOARD_FOCUS_SCROLL_DURATION);
1293   }
1294 }
1295
1296 Animation ItemView::DoAnchoring()
1297 {
1298   Animation anchoringAnimation;
1299   Actor self = Self();
1300
1301   if (mActiveLayout && mAnchoringEnabled)
1302   {
1303     float anchorPosition = mActiveLayout->GetClosestAnchorPosition( GetCurrentLayoutPosition(0) );
1304
1305     anchoringAnimation = Animation::New(mAnchoringDuration);
1306     anchoringAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), anchorPosition, AlphaFunctions::EaseOut );
1307     anchoringAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(anchorPosition, self.GetCurrentSize()), AlphaFunctions::EaseOut );
1308     anchoringAnimation.AnimateTo( Property(self, mPropertyScrollSpeed), 0.0f, AlphaFunctions::EaseOut );
1309     if(!mIsFlicking)
1310     {
1311       AnimateScrollOvershoot(0.0f);
1312     }
1313   }
1314
1315   return anchoringAnimation;
1316 }
1317
1318 void ItemView::OnScrollFinished(Animation& source)
1319 {
1320   Actor self = Self();
1321
1322   RemoveAnimation(mScrollAnimation); // mScrollAnimation is used to query whether we're scrolling
1323
1324   mScrollCompletedSignalV2.Emit(GetCurrentScrollPosition());
1325
1326   if(mIsFlicking && fabsf(mScrollOvershoot) > Math::MACHINE_EPSILON_1)
1327   {
1328     AnimateScrollOvershoot( mScrollOvershoot > 0.0f ? 1.0f : -1.0f, true);
1329   }
1330   else
1331   {
1332     // Reset the overshoot
1333     AnimateScrollOvershoot( 0.0f );
1334   }
1335   mIsFlicking = false;
1336
1337   mScrollOvershoot = 0.0f;
1338 }
1339
1340 void ItemView::OnLayoutActivationScrollFinished(Animation& source)
1341 {
1342   RemoveAnimation(mScrollAnimation);
1343   mRefreshEnabled = true;
1344   DoRefresh(GetCurrentLayoutPosition(0), true);
1345 }
1346
1347 void ItemView::OnOvershootOnFinished(Animation& animation)
1348 {
1349   mAnimatingOvershootOn = false;
1350   mScrollOvershootAnimation.FinishedSignal().Disconnect(this, &ItemView::OnOvershootOnFinished);
1351   RemoveAnimation(mScrollOvershootAnimation);
1352   if(mAnimateOvershootOff)
1353   {
1354     AnimateScrollOvershoot(0.0f);
1355   }
1356 }
1357
1358 void ItemView::ScrollToItem(unsigned int itemId, float durationSeconds)
1359 {
1360   Actor self = Self();
1361   const Vector3 layoutSize = Self().GetCurrentSize();
1362   float firstItemScrollPosition = ClampFirstItemPosition(mActiveLayout->GetItemScrollToPosition(itemId), layoutSize, *mActiveLayout);
1363
1364   if(durationSeconds > 0.0f)
1365   {
1366     RemoveAnimation(mScrollAnimation);
1367     mScrollAnimation = Animation::New(durationSeconds);
1368     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1369     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1370     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1371     mScrollAnimation.Play();
1372   }
1373   else
1374   {
1375     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1376     AnimateScrollOvershoot(0.0f);
1377   }
1378
1379   mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1380   mRefreshEnabled = true;
1381 }
1382
1383 void ItemView::RemoveAnimation(Animation& animation)
1384 {
1385   if(animation)
1386   {
1387     // Cease animating, and reset handle.
1388     animation.Clear();
1389     animation.Reset();
1390   }
1391 }
1392
1393 void ItemView::CalculateDomainSize(const Vector3& layoutSize)
1394 {
1395   Actor self = Self();
1396
1397   Vector3 firstItemPosition(Vector3::ZERO);
1398   Vector3 lastItemPosition(Vector3::ZERO);
1399
1400   if(mActiveLayout)
1401   {
1402     firstItemPosition = mActiveLayout->GetItemPosition( 0,0,layoutSize );
1403
1404     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), layoutSize);
1405     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1406     lastItemPosition = mActiveLayout->GetItemPosition( fabs(minLayoutPosition),fabs(minLayoutPosition),layoutSize );
1407
1408     float domainSize;
1409
1410     if(IsHorizontal(mActiveLayout->GetOrientation()))
1411     {
1412       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.x, 0.0f));
1413       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.x, 0.0f));
1414       domainSize = fabs(firstItemPosition.x - lastItemPosition.x);
1415     }
1416     else
1417     {
1418       self.SetProperty(mPropertyPositionMin, Vector3(0.0f, firstItemPosition.y, 0.0f));
1419       self.SetProperty(mPropertyPositionMax, Vector3(0.0f, lastItemPosition.y, 0.0f));
1420       domainSize = fabs(firstItemPosition.y - lastItemPosition.y);
1421     }
1422
1423     mScrollConnector.SetScrollDomain(minLayoutPosition, 0.0f, domainSize);
1424
1425     bool isLayoutScrollable = IsLayoutScrollable(layoutSize);
1426     self.SetProperty(mPropertyCanScrollVertical, isLayoutScrollable);
1427     self.SetProperty(mPropertyCanScrollHorizontal, false);
1428   }
1429 }
1430
1431 Vector3 ItemView::GetDomainSize() const
1432 {
1433   Actor self = Self();
1434
1435   float minScrollPosition = self.GetProperty<float>(mPropertyPositionMin);
1436   float maxScrollPosition = self.GetProperty<float>(mPropertyPositionMax);
1437
1438   return Vector3(0.0f, fabs(maxScrollPosition - minScrollPosition), 0.0f);
1439 }
1440
1441 bool ItemView::IsLayoutScrollable(const Vector3& layoutSize)
1442 {
1443   Actor self = Self();
1444
1445   float currentLayoutPosition = ClampFirstItemPosition( GetCurrentLayoutPosition(0), layoutSize, *mActiveLayout );
1446   float forwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition + 1.0, layoutSize, *mActiveLayout);
1447   float backwardClampedPosition = ClampFirstItemPosition(currentLayoutPosition - 1.0, layoutSize, *mActiveLayout);
1448
1449   return (fabs(forwardClampedPosition - backwardClampedPosition) > Math::MACHINE_EPSILON_0);
1450 }
1451
1452 float ItemView::GetScrollPosition(float layoutPosition, const Vector3& layoutSize) const
1453 {
1454   Vector3 firstItemPosition( mActiveLayout->GetItemPosition(0, layoutPosition, layoutSize ) );
1455   return IsHorizontal(mActiveLayout->GetOrientation()) ? firstItemPosition.x: firstItemPosition.y;
1456 }
1457
1458 Vector3 ItemView::GetCurrentScrollPosition() const
1459 {
1460   float currentLayoutPosition = GetCurrentLayoutPosition(0);
1461   return Vector3(0.0f, GetScrollPosition(currentLayoutPosition, Self().GetCurrentSize()), 0.0f);
1462 }
1463
1464 void ItemView::AddOverlay(Actor actor)
1465 {
1466   Self().Add(actor);
1467 }
1468
1469 void ItemView::RemoveOverlay(Actor actor)
1470 {
1471   Self().Remove(actor);
1472 }
1473
1474 void ItemView::ScrollTo(const Vector3& position, float duration)
1475 {
1476   Actor self = Self();
1477   const Vector3 layoutSize = Self().GetCurrentSize();
1478
1479   float firstItemScrollPosition = ClampFirstItemPosition(position.y, layoutSize, *mActiveLayout);
1480
1481   if(duration > 0.0f)
1482   {
1483     RemoveAnimation(mScrollAnimation);
1484     mScrollAnimation = Animation::New(duration);
1485     mScrollAnimation.AnimateTo( Property( mScrollPositionObject, ScrollConnector::SCROLL_POSITION ), firstItemScrollPosition, AlphaFunctions::EaseOut );
1486     mScrollAnimation.AnimateTo( Property(self, mPropertyPosition), GetScrollPosition(firstItemScrollPosition, layoutSize), AlphaFunctions::EaseOut );
1487     mScrollAnimation.FinishedSignal().Connect(this, &ItemView::OnScrollFinished);
1488     mScrollAnimation.Play();
1489   }
1490   else
1491   {
1492     mScrollPositionObject.SetProperty( ScrollConnector::SCROLL_POSITION, firstItemScrollPosition );
1493     AnimateScrollOvershoot(0.0f);
1494   }
1495
1496   mScrollStartedSignalV2.Emit(GetCurrentScrollPosition());
1497   mRefreshEnabled = true;
1498 }
1499
1500 void ItemView::SetOvershootEffectColor( const Vector4& color )
1501 {
1502   mOvershootEffectColor = color;
1503   if( mOvershootOverlay )
1504   {
1505     mOvershootOverlay.SetColor( color );
1506   }
1507 }
1508
1509 void ItemView::SetOvershootEnabled( bool enable )
1510 {
1511   Actor self = Self();
1512   if( enable )
1513   {
1514     Property::Index effectOvershootPropertyIndex = Property::INVALID_INDEX;
1515     mOvershootOverlay = CreateBouncingEffectActor( effectOvershootPropertyIndex );
1516     mOvershootOverlay.SetColor(mOvershootEffectColor);
1517     mOvershootOverlay.SetParentOrigin(ParentOrigin::TOP_LEFT);
1518     mOvershootOverlay.SetAnchorPoint(AnchorPoint::TOP_LEFT);
1519     mOvershootOverlay.SetDrawMode(DrawMode::OVERLAY);
1520     self.Add(mOvershootOverlay);
1521
1522     Constraint constraint = Constraint::New<Vector3>( Actor::SIZE,
1523                                                       ParentSource( mPropertyScrollDirection ),
1524                                                       Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1525                                                       ParentSource( Actor::SIZE ),
1526                                                       OvershootOverlaySizeConstraint() );
1527     mOvershootOverlay.ApplyConstraint(constraint);
1528     mOvershootOverlay.SetSize(OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.width, OVERSHOOT_BOUNCE_ACTOR_DEFAULT_SIZE.height);
1529
1530     constraint = Constraint::New<Quaternion>( Actor::ROTATION,
1531                                               ParentSource( mPropertyScrollDirection ),
1532                                               Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1533                                               OvershootOverlayRotationConstraint() );
1534     mOvershootOverlay.ApplyConstraint(constraint);
1535
1536     constraint = Constraint::New<Vector3>( Actor::POSITION,
1537                                            ParentSource( Actor::SIZE ),
1538                                            ParentSource( mPropertyScrollDirection ),
1539                                            Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1540                                            OvershootOverlayPositionConstraint() );
1541     mOvershootOverlay.ApplyConstraint(constraint);
1542
1543     constraint = Constraint::New<bool>( Actor::VISIBLE,
1544                                         ParentSource( mPropertyCanScrollVertical ),
1545                                         OvershootOverlayVisibilityConstraint() );
1546     mOvershootOverlay.ApplyConstraint(constraint);
1547
1548     Actor self = Self();
1549     constraint = Constraint::New<float>( effectOvershootPropertyIndex,
1550                                          Source( mScrollPositionObject, ScrollConnector::OVERSHOOT ),
1551                                          EqualToConstraint() );
1552     mOvershootOverlay.ApplyConstraint(constraint);
1553   }
1554   else
1555   {
1556     if( mOvershootOverlay )
1557     {
1558       self.Remove(mOvershootOverlay);
1559       mOvershootOverlay.Reset();
1560     }
1561   }
1562 }
1563
1564 float ItemView::CalculateScrollOvershoot()
1565 {
1566   float overshoot = 0.0f;
1567
1568   if(mActiveLayout)
1569   {
1570     // The overshoot must be calculated from the accumulated pan gesture displacement
1571     // since the pan gesture starts.
1572     Actor self = Self();
1573     float scrollDistance = CalculateScrollDistance(mTotalPanDisplacement, *mActiveLayout) * mActiveLayout->GetScrollSpeedFactor();
1574     float positionDelta = GetCurrentLayoutPosition(0) + scrollDistance;
1575     float minLayoutPosition = mActiveLayout->GetMinimumLayoutPosition(mItemFactory.GetNumberOfItems(), Self().GetCurrentSize());
1576     self.SetProperty(mPropertyMinimumLayoutPosition, minLayoutPosition);
1577     float clamppedPosition = std::min(0.0f, std::max(minLayoutPosition, positionDelta));
1578     overshoot = positionDelta - clamppedPosition;
1579   }
1580
1581   return overshoot;
1582 }
1583
1584 void ItemView::AnimateScrollOvershoot(float overshootAmount, bool animateBack)
1585 {
1586   bool animatingOn = fabsf(overshootAmount) > Math::MACHINE_EPSILON_1;
1587
1588   // make sure we animate back if needed
1589   mAnimateOvershootOff = animateBack || (!animatingOn && mAnimatingOvershootOn);
1590
1591   if( mAnimatingOvershootOn )
1592   {
1593     // animating on, do not allow animate off
1594     return;
1595   }
1596
1597   Actor self = Self();
1598   float currentOvershoot = mScrollPositionObject.GetProperty<float>(ScrollConnector::OVERSHOOT);
1599   float duration = DEFAULT_OVERSHOOT_ANIMATION_DURATION * (animatingOn ? (1.0f - fabsf(currentOvershoot)) : fabsf(currentOvershoot));
1600
1601   RemoveAnimation(mScrollOvershootAnimation);
1602   mScrollOvershootAnimation = Animation::New(duration);
1603   mScrollOvershootAnimation.FinishedSignal().Connect(this, &ItemView::OnOvershootOnFinished);
1604   mScrollOvershootAnimation.AnimateTo( Property(mScrollPositionObject, ScrollConnector::OVERSHOOT), overshootAmount, TimePeriod(0.0f, duration) );
1605   mScrollOvershootAnimation.Play();
1606
1607   mAnimatingOvershootOn = animatingOn;
1608 }
1609
1610 void ItemView::SetItemsParentOrigin( const Vector3& parentOrigin )
1611 {
1612   if( parentOrigin != mItemsParentOrigin )
1613   {
1614     mItemsParentOrigin = parentOrigin;
1615     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1616     {
1617       iter->second.SetParentOrigin(parentOrigin);
1618     }
1619   }
1620 }
1621
1622 Vector3 ItemView::GetItemsParentOrigin() const
1623 {
1624   return mItemsParentOrigin;
1625 }
1626
1627 void ItemView::SetItemsAnchorPoint( const Vector3& anchorPoint )
1628 {
1629   if( anchorPoint != mItemsAnchorPoint )
1630   {
1631     mItemsAnchorPoint = anchorPoint;
1632     for (ItemPoolIter iter = mItemPool.begin(); iter != mItemPool.end(); ++iter)
1633     {
1634       iter->second.SetAnchorPoint(anchorPoint);
1635     }
1636   }
1637 }
1638
1639 Vector3 ItemView::GetItemsAnchorPoint() const
1640 {
1641   return mItemsAnchorPoint;
1642 }
1643
1644 void ItemView::GetItemsRange(ItemRange& range)
1645 {
1646   range.begin = mItemPool.begin()->first;
1647   range.end = mItemPool.rbegin()->first + 1;
1648 }
1649
1650 void ItemView::OnScrollPositionChanged( float position )
1651 {
1652   // Cancel scroll animation to prevent any fighting of setting the scroll position property.
1653   RemoveAnimation(mScrollAnimation);
1654
1655   // Refresh the cache immediately when the scroll position is changed.
1656   DoRefresh(position, false); // No need to cache extra items.
1657 }
1658
1659 } // namespace Internal
1660
1661 } // namespace Toolkit
1662
1663 } // namespace Dali