1 /* 2 * Copyright (C) 2004, 2006, 2007, 2008 Apple Inc. All rights reserved. 3 * Copyright (C) 2009 Holger Hans Peter Freyther 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #ifndef ScrollView_h 28 #define ScrollView_h 29 30 #include "platform/PlatformExport.h" 31 #include "platform/Widget.h" 32 #include "platform/geometry/IntRect.h" 33 #include "platform/scroll/ScrollTypes.h" 34 #include "platform/scroll/ScrollableArea.h" 35 #include "platform/scroll/Scrollbar.h" 36 37 #include "wtf/HashSet.h" 38 39 namespace WebCore { 40 41 class HostWindow; 42 class Scrollbar; 43 44 class PLATFORM_EXPORT ScrollView : public Widget, public ScrollableArea { 45 public: 46 ~ScrollView(); 47 48 // ScrollableArea functions. 49 virtual int scrollSize(ScrollbarOrientation) const OVERRIDE; 50 virtual void setScrollOffset(const IntPoint&) OVERRIDE; 51 virtual bool isScrollCornerVisible() const OVERRIDE; 52 virtual void scrollbarStyleChanged(int newStyle, bool forceUpdate) OVERRIDE; 53 virtual bool userInputScrollable(ScrollbarOrientation) const OVERRIDE; 54 virtual bool shouldPlaceVerticalScrollbarOnLeft() const OVERRIDE; 55 56 virtual void notifyPageThatContentAreaWillPaint() const; 57 58 // NOTE: This should only be called by the overriden setScrollOffset from ScrollableArea. 59 virtual void scrollTo(const IntSize& newOffset); 60 61 // The window thats hosts the ScrollView. The ScrollView will communicate scrolls and repaints to the 62 // host window in the window's coordinate space. 63 virtual HostWindow* hostWindow() const = 0; 64 65 // Returns a clip rect in host window coordinates. Used to clip the blit on a scroll. 66 virtual IntRect windowClipRect(bool clipToContents = true) const = 0; 67 68 // Functions for child manipulation and inspection. 69 const HashSet<RefPtr<Widget> >* children() const { return &m_children; } 70 virtual void addChild(PassRefPtr<Widget>); 71 virtual void removeChild(Widget*); 72 73 // If the scroll view does not use a native widget, then it will have cross-platform Scrollbars. These functions 74 // can be used to obtain those scrollbars. 75 virtual Scrollbar* horizontalScrollbar() const OVERRIDE { return m_horizontalScrollbar.get(); } 76 virtual Scrollbar* verticalScrollbar() const OVERRIDE { return m_verticalScrollbar.get(); } 77 bool isScrollViewScrollbar(const Widget* child) const { return horizontalScrollbar() == child || verticalScrollbar() == child; } 78 79 void positionScrollbarLayers(); 80 81 // Functions for setting and retrieving the scrolling mode in each axis (horizontal/vertical). The mode has values of 82 // AlwaysOff, AlwaysOn, and Auto. AlwaysOff means never show a scrollbar, AlwaysOn means always show a scrollbar. 83 // Auto means show a scrollbar only when one is needed. 84 // Note that for platforms with native widgets, these modes are considered advisory. In other words the underlying native 85 // widget may choose not to honor the requested modes. 86 void setScrollbarModes(ScrollbarMode horizontalMode, ScrollbarMode verticalMode, bool horizontalLock = false, bool verticalLock = false); 87 void setHorizontalScrollbarMode(ScrollbarMode mode, bool lock = false) { setScrollbarModes(mode, verticalScrollbarMode(), lock, verticalScrollbarLock()); } 88 void setVerticalScrollbarMode(ScrollbarMode mode, bool lock = false) { setScrollbarModes(horizontalScrollbarMode(), mode, horizontalScrollbarLock(), lock); }; 89 void scrollbarModes(ScrollbarMode& horizontalMode, ScrollbarMode& verticalMode) const; 90 ScrollbarMode horizontalScrollbarMode() const { ScrollbarMode horizontal, vertical; scrollbarModes(horizontal, vertical); return horizontal; } 91 ScrollbarMode verticalScrollbarMode() const { ScrollbarMode horizontal, vertical; scrollbarModes(horizontal, vertical); return vertical; } 92 93 void setHorizontalScrollbarLock(bool lock = true) { m_horizontalScrollbarLock = lock; } 94 bool horizontalScrollbarLock() const { return m_horizontalScrollbarLock; } 95 void setVerticalScrollbarLock(bool lock = true) { m_verticalScrollbarLock = lock; } 96 bool verticalScrollbarLock() const { return m_verticalScrollbarLock; } 97 98 void setScrollingModesLock(bool lock = true) { m_horizontalScrollbarLock = m_verticalScrollbarLock = lock; } 99 100 virtual void setCanHaveScrollbars(bool); 101 bool canHaveScrollbars() const { return horizontalScrollbarMode() != ScrollbarAlwaysOff || verticalScrollbarMode() != ScrollbarAlwaysOff; } 102 103 // By default you only receive paint events for the area that is visible. In the case of using a 104 // tiled backing store, this function can be set, so that the view paints the entire contents. 105 bool paintsEntireContents() const { return m_paintsEntireContents; } 106 void setPaintsEntireContents(bool); 107 108 // By default, paint events are clipped to the visible area. If set to 109 // false, paint events are no longer clipped. paintsEntireContents() implies !clipsRepaints(). 110 bool clipsRepaints() const { return m_clipsRepaints; } 111 void setClipsRepaints(bool); 112 113 // Overridden by FrameView to create custom CSS scrollbars if applicable. 114 virtual PassRefPtr<Scrollbar> createScrollbar(ScrollbarOrientation); 115 116 // Whether or not a scroll view will blit visible contents when it is scrolled. Blitting is disabled in situations 117 // where it would cause rendering glitches (such as with fixed backgrounds or when the view is partially transparent). 118 void setCanBlitOnScroll(bool); 119 bool canBlitOnScroll() const; 120 121 // The visible content rect has a location that is the scrolled offset of the document. The width and height are the viewport width 122 // and height. By default the scrollbars themselves are excluded from this rectangle, but an optional boolean argument allows them to be 123 // included. 124 virtual IntRect visibleContentRect(IncludeScrollbarsInRect = ExcludeScrollbars) const OVERRIDE; 125 IntSize visibleSize() const { return visibleContentRect().size(); } 126 virtual int visibleWidth() const OVERRIDE { return visibleContentRect().width(); } 127 virtual int visibleHeight() const OVERRIDE { return visibleContentRect().height(); } 128 129 // visibleContentRect().size() is computed from unscaledVisibleContentSize() divided by the value of visibleContentScaleFactor. 130 // For the main frame, visibleContentScaleFactor is equal to the page's pageScaleFactor; it's 1 otherwise. 131 IntSize unscaledVisibleContentSize(IncludeScrollbarsInRect = ExcludeScrollbars) const; 132 virtual float visibleContentScaleFactor() const { return 1; } 133 134 // Offset used to convert incoming input events while emulating device metics. 135 virtual IntSize inputEventsOffsetForEmulation() const { return IntSize(); } 136 137 // Scale used to convert incoming input events. Usually the same as visibleContentScaleFactor(), unless specifically changed. 138 virtual float inputEventsScaleFactor() const { return visibleContentScaleFactor(); } 139 140 // Functions for getting/setting the size of the document contained inside the ScrollView (as an IntSize or as individual width and height 141 // values). 142 virtual IntSize contentsSize() const OVERRIDE; // Always at least as big as the visibleWidth()/visibleHeight(). 143 int contentsWidth() const { return contentsSize().width(); } 144 int contentsHeight() const { return contentsSize().height(); } 145 virtual void setContentsSize(const IntSize&); 146 147 // Functions for querying the current scrolled position (both as a point, a size, or as individual X and Y values). 148 virtual IntPoint scrollPosition() const OVERRIDE { return visibleContentRect().location(); } 149 IntSize scrollOffset() const { return toIntSize(visibleContentRect().location()); } // Gets the scrolled position as an IntSize. Convenient for adding to other sizes. 150 virtual IntPoint maximumScrollPosition() const OVERRIDE; // The maximum position we can be scrolled to. 151 virtual IntPoint minimumScrollPosition() const OVERRIDE; // The minimum position we can be scrolled to. 152 // Adjust the passed in scroll position to keep it between the minimum and maximum positions. 153 IntPoint adjustScrollPositionWithinRange(const IntPoint&) const; 154 int scrollX() const { return scrollPosition().x(); } 155 int scrollY() const { return scrollPosition().y(); } 156 157 virtual IntSize overhangAmount() const OVERRIDE; 158 159 void cacheCurrentScrollPosition() { m_cachedScrollPosition = scrollPosition(); } 160 IntPoint cachedScrollPosition() const { return m_cachedScrollPosition; } 161 162 // Functions for scrolling the view. 163 virtual void setScrollPosition(const IntPoint&); 164 void scrollBy(const IntSize& s) { return setScrollPosition(scrollPosition() + s); } 165 166 bool scroll(ScrollDirection, ScrollGranularity); 167 168 // Scroll the actual contents of the view (either blitting or invalidating as needed). 169 void scrollContents(const IntSize& scrollDelta); 170 171 // This gives us a means of blocking painting on our scrollbars until the first layout has occurred. 172 void setScrollbarsSuppressed(bool suppressed, bool repaintOnUnsuppress = false); 173 bool scrollbarsSuppressed() const { return m_scrollbarsSuppressed; } 174 175 IntPoint rootViewToContents(const IntPoint&) const; 176 IntPoint contentsToRootView(const IntPoint&) const; 177 IntRect rootViewToContents(const IntRect&) const; 178 IntRect contentsToRootView(const IntRect&) const; 179 180 // Event coordinates are assumed to be in the coordinate space of a window that contains 181 // the entire widget hierarchy. It is up to the platform to decide what the precise definition 182 // of containing window is. (For example on Mac it is the containing NSWindow.) 183 IntPoint windowToContents(const IntPoint&) const; 184 IntPoint contentsToWindow(const IntPoint&) const; 185 IntRect windowToContents(const IntRect&) const; 186 IntRect contentsToWindow(const IntRect&) const; 187 188 // Functions for converting to and from screen coordinates. 189 IntRect contentsToScreen(const IntRect&) const; 190 IntPoint screenToContents(const IntPoint&) const; 191 192 // The purpose of this function is to answer whether or not the scroll view is currently visible. Animations and painting updates can be suspended if 193 // we know that we are either not in a window right now or if that window is not visible. 194 bool isOffscreen() const; 195 196 // These functions are used to enable scrollbars to avoid window resizer controls that overlap the scroll view. This happens on Mac 197 // for example. 198 virtual IntRect windowResizerRect() const { return IntRect(); } 199 bool containsScrollbarsAvoidingResizer() const; 200 void adjustScrollbarsAvoidingResizerCount(int overlapDelta); 201 void windowResizerRectChanged(); 202 203 virtual void setParent(Widget*) OVERRIDE; // Overridden to update the overlapping scrollbar count. 204 205 // Called when our frame rect changes (or the rect/scroll position of an ancestor changes). 206 virtual void frameRectsChanged(); 207 208 // Widget override to update our scrollbars and notify our contents of the resize. 209 virtual void setFrameRect(const IntRect&); 210 211 // Widget override to notify our contents of a cliprect change. 212 virtual void clipRectChanged() OVERRIDE; 213 214 // For platforms that need to hit test scrollbars from within the engine's event handlers (like Win32). 215 Scrollbar* scrollbarAtPoint(const IntPoint& windowPoint); 216 217 virtual IntPoint convertChildToSelf(const Widget* child, const IntPoint& point) const 218 { 219 IntPoint newPoint = point; 220 if (!isScrollViewScrollbar(child)) 221 newPoint = point - scrollOffset(); 222 newPoint.moveBy(child->location()); 223 return newPoint; 224 } 225 226 virtual IntPoint convertSelfToChild(const Widget* child, const IntPoint& point) const 227 { 228 IntPoint newPoint = point; 229 if (!isScrollViewScrollbar(child)) 230 newPoint = point + scrollOffset(); 231 newPoint.moveBy(-child->location()); 232 return newPoint; 233 } 234 235 // Widget override. Handles painting of the contents of the view as well as the scrollbars. 236 virtual void paint(GraphicsContext*, const IntRect&); 237 void paintScrollbars(GraphicsContext*, const IntRect&); 238 239 // Widget overrides to ensure that our children's visibility status is kept up to date when we get shown and hidden. 240 virtual void show(); 241 virtual void hide(); 242 virtual void setParentVisible(bool); 243 244 // Pan scrolling. 245 static const int noPanScrollRadius = 15; 246 void addPanScrollIcon(const IntPoint&); 247 void removePanScrollIcon(); 248 void paintPanScrollIcon(GraphicsContext*); 249 250 virtual bool isPointInScrollbarCorner(const IntPoint&); 251 virtual bool scrollbarCornerPresent() const; 252 virtual IntRect scrollCornerRect() const; 253 virtual void paintScrollCorner(GraphicsContext*, const IntRect& cornerRect); 254 virtual void paintScrollbar(GraphicsContext*, Scrollbar*, const IntRect&); 255 256 virtual IntRect convertFromScrollbarToContainingView(const Scrollbar*, const IntRect&) const OVERRIDE; 257 virtual IntRect convertFromContainingViewToScrollbar(const Scrollbar*, const IntRect&) const OVERRIDE; 258 virtual IntPoint convertFromScrollbarToContainingView(const Scrollbar*, const IntPoint&) const OVERRIDE; 259 virtual IntPoint convertFromContainingViewToScrollbar(const Scrollbar*, const IntPoint&) const OVERRIDE; 260 261 void calculateAndPaintOverhangAreas(GraphicsContext*, const IntRect& dirtyRect); 262 void calculateAndPaintOverhangBackground(GraphicsContext*, const IntRect& dirtyRect); 263 264 virtual bool isScrollView() const OVERRIDE { return true; } 265 266 protected: 267 ScrollView(); 268 269 virtual void repaintContentRectangle(const IntRect&); 270 virtual void paintContents(GraphicsContext*, const IntRect& damageRect) = 0; 271 272 virtual void paintOverhangAreas(GraphicsContext*, const IntRect& horizontalOverhangArea, const IntRect& verticalOverhangArea, const IntRect& dirtyRect); 273 274 virtual void scrollbarExistenceDidChange() = 0; 275 // These functions are used to create/destroy scrollbars. 276 void setHasHorizontalScrollbar(bool); 277 void setHasVerticalScrollbar(bool); 278 279 virtual void updateScrollCorner(); 280 virtual void invalidateScrollCornerRect(const IntRect&) OVERRIDE; 281 282 // Scroll the content by blitting the pixels. 283 virtual bool scrollContentsFastPath(const IntSize& scrollDelta, const IntRect& rectToScroll, const IntRect& clipRect); 284 // Scroll the content by invalidating everything. 285 virtual void scrollContentsSlowPath(const IntRect& updateRect); 286 287 void setScrollOrigin(const IntPoint&, bool updatePositionAtAll, bool updatePositionSynchronously); 288 289 // Subclassed by FrameView to check the writing-mode of the document. 290 virtual bool isVerticalDocument() const { return true; } 291 virtual bool isFlippedDocument() const { return false; } 292 293 // Called to update the scrollbars to accurately reflect the state of the view. 294 void updateScrollbars(const IntSize& desiredOffset); 295 296 IntSize excludeScrollbars(const IntSize&) const; 297 298 private: 299 RefPtr<Scrollbar> m_horizontalScrollbar; 300 RefPtr<Scrollbar> m_verticalScrollbar; 301 ScrollbarMode m_horizontalScrollbarMode; 302 ScrollbarMode m_verticalScrollbarMode; 303 304 bool m_horizontalScrollbarLock; 305 bool m_verticalScrollbarLock; 306 307 HashSet<RefPtr<Widget> > m_children; 308 309 // This bool is unused on Mac OS because we directly ask the platform widget 310 // whether it is safe to blit on scroll. 311 bool m_canBlitOnScroll; 312 313 IntSize m_scrollOffset; // FIXME: Would rather store this as a position, but we will wait to make this change until more code is shared. 314 IntPoint m_cachedScrollPosition; 315 IntSize m_contentsSize; 316 317 int m_scrollbarsAvoidingResizer; 318 bool m_scrollbarsSuppressed; 319 320 bool m_inUpdateScrollbars; 321 unsigned m_updateScrollbarsPass; 322 323 IntPoint m_panScrollIconPoint; 324 bool m_drawPanScrollIcon; 325 326 bool m_paintsEntireContents; 327 bool m_clipsRepaints; 328 329 void init(); 330 void destroy(); 331 332 IntRect rectToCopyOnScroll() const; 333 334 // Called when the scroll position within this view changes. FrameView overrides this to generate repaint invalidations. 335 virtual void repaintFixedElementsAfterScrolling() { } 336 virtual void updateFixedElementsAfterScrolling() { } 337 338 void calculateOverhangAreasForPainting(IntRect& horizontalOverhangRect, IntRect& verticalOverhangRect); 339 void updateOverhangAreas(); 340 341 int pageStep(ScrollbarOrientation) const; 342 }; // class ScrollView 343 344 inline ScrollView* toScrollView(Widget* widget) 345 { 346 ASSERT_WITH_SECURITY_IMPLICATION(!widget || widget->isScrollView()); 347 return static_cast<ScrollView*>(widget); 348 } 349 350 inline const ScrollView* toScrollView(const Widget* widget) 351 { 352 ASSERT_WITH_SECURITY_IMPLICATION(!widget || widget->isScrollView()); 353 return static_cast<const ScrollView*>(widget); 354 } 355 356 // This will catch anyone doing an unnecessary cast. 357 void toScrollView(const ScrollView*); 358 359 } // namespace WebCore 360 361 #endif // ScrollView_h 362
