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