1 /* 2 * Copyright 2006, Haiku. 3 * Distributed under the terms of the MIT License. 4 * 5 * Authors: 6 * Ingo Weinhold <bonefish@cs.tu-berlin.de> 7 */ 8 9 #include "ScrollableView.h" 10 11 #include <View.h> 12 13 // constructor ScrollableView()14ScrollableView::ScrollableView() 15 : Scrollable() 16 { 17 } 18 19 // destructor ~ScrollableView()20ScrollableView::~ScrollableView() 21 { 22 } 23 24 // ScrollOffsetChanged 25 void ScrollOffsetChanged(BPoint oldOffset,BPoint newOffset)26ScrollableView::ScrollOffsetChanged(BPoint oldOffset, BPoint newOffset) 27 { 28 if (BView* view = dynamic_cast<BView*>(this)) { 29 // We keep it simple: The part of the data rect we shall show now 30 // has existed before as well (even if partially or completely 31 // obscured), so we let CopyBits() do the messy details. 32 BRect bounds(view->Bounds()); 33 view->CopyBits(bounds.OffsetByCopy(newOffset - oldOffset), bounds); 34 // move our children 35 for (int32 i = 0; BView* child = view->ChildAt(i); i++) 36 child->MoveTo(child->Frame().LeftTop() + oldOffset - newOffset); 37 } 38 } 39 40