1 /* 2 Copyright (C) 1997 Martin Jones (mjones (at) kde.org) 3 (C) 1998 Waldo Bastian (bastian (at) kde.org) 4 (C) 1998, 1999 Torben Weis (weis (at) kde.org) 5 (C) 1999 Lars Knoll (knoll (at) kde.org) 6 (C) 1999 Antti Koivisto (koivisto (at) kde.org) 7 Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved. 8 9 This library is free software; you can redistribute it and/or 10 modify it under the terms of the GNU Library General Public 11 License as published by the Free Software Foundation; either 12 version 2 of the License, or (at your option) any later version. 13 14 This library is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 Library General Public License for more details. 18 19 You should have received a copy of the GNU Library General Public License 20 along with this library; see the file COPYING.LIB. If not, write to 21 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 22 Boston, MA 02110-1301, USA. 23 */ 24 25 #ifndef FrameView_h 26 #define FrameView_h 27 28 #include "core/frame/FrameViewAutoSizeInfo.h" 29 #include "core/rendering/PaintPhase.h" 30 #include "platform/RuntimeEnabledFeatures.h" 31 #include "platform/geometry/LayoutRect.h" 32 #include "platform/graphics/Color.h" 33 #include "platform/scroll/ScrollView.h" 34 #include "wtf/Forward.h" 35 #include "wtf/OwnPtr.h" 36 #include "wtf/text/WTFString.h" 37 38 namespace blink { 39 40 class AXObjectCache; 41 class DocumentLifecycle; 42 class Cursor; 43 class Element; 44 class FloatSize; 45 class HTMLFrameOwnerElement; 46 class LocalFrame; 47 class KURL; 48 class Node; 49 class Page; 50 class RenderBox; 51 class RenderEmbeddedObject; 52 class RenderObject; 53 class RenderScrollbarPart; 54 class RenderView; 55 class RenderWidget; 56 struct CompositedSelectionBound; 57 58 typedef unsigned long long DOMTimeStamp; 59 60 // FIXME: Oilpan: move Widget (and thereby FrameView) to the heap. 61 class FrameView FINAL : public ScrollView { 62 public: 63 friend class RenderView; 64 friend class Internals; 65 66 static PassRefPtr<FrameView> create(LocalFrame*); 67 static PassRefPtr<FrameView> create(LocalFrame*, const IntSize& initialSize); 68 69 virtual ~FrameView(); 70 71 virtual HostWindow* hostWindow() const OVERRIDE; 72 73 virtual void invalidateRect(const IntRect&) OVERRIDE; 74 virtual void setFrameRect(const IntRect&) OVERRIDE; 75 76 LocalFrame& frame() const 77 { 78 ASSERT(m_frame); 79 return *m_frame; 80 } 81 82 Page* page() const; 83 84 RenderView* renderView() const; 85 86 virtual void setCanHaveScrollbars(bool) OVERRIDE; 87 88 virtual PassRefPtr<Scrollbar> createScrollbar(ScrollbarOrientation) OVERRIDE; 89 90 virtual void setContentsSize(const IntSize&) OVERRIDE; 91 IntPoint clampOffsetAtScale(const IntPoint& offset, float scale) const; 92 93 void layout(bool allowSubtree = true); 94 bool didFirstLayout() const; 95 void scheduleRelayout(); 96 void scheduleRelayoutOfSubtree(RenderObject*); 97 bool layoutPending() const; 98 bool isInPerformLayout() const; 99 100 void setCanInvalidatePaintDuringPerformLayout(bool b) { m_canInvalidatePaintDuringPerformLayout = b; } 101 bool canInvalidatePaintDuringPerformLayout() const { return m_canInvalidatePaintDuringPerformLayout; } 102 103 RenderObject* layoutRoot(bool onlyDuringLayout = false) const; 104 void clearLayoutSubtreeRoot() { m_layoutSubtreeRoot = 0; } 105 int layoutCount() const { return m_layoutCount; } 106 107 bool needsLayout() const; 108 void setNeedsLayout(); 109 110 void setNeedsUpdateWidgetPositions() { m_needsUpdateWidgetPositions = true; } 111 112 // Methods for getting/setting the size Blink should use to layout the contents. 113 IntSize layoutSize(IncludeScrollbarsInRect = ExcludeScrollbars) const; 114 void setLayoutSize(const IntSize&); 115 116 // If this is set to false, the layout size will need to be explicitly set by the owner. 117 // E.g. WebViewImpl sets its mainFrame's layout size manually 118 void setLayoutSizeFixedToFrameSize(bool isFixed) { m_layoutSizeFixedToFrameSize = isFixed; } 119 bool layoutSizeFixedToFrameSize() { return m_layoutSizeFixedToFrameSize; } 120 121 bool needsFullPaintInvalidation() const { return m_doFullPaintInvalidation; } 122 void setNeedsFullPaintInvalidation() { m_doFullPaintInvalidation = true; } 123 124 void updateAcceleratedCompositingSettings(); 125 126 void recalcOverflowAfterStyleChange(); 127 128 bool isEnclosedInCompositingLayer() const; 129 130 void resetScrollbars(); 131 void prepareForDetach(); 132 void detachCustomScrollbars(); 133 virtual void recalculateScrollbarOverlayStyle(); 134 135 void clear(); 136 137 bool isTransparent() const; 138 void setTransparent(bool isTransparent); 139 140 // True if the FrameView is not transparent, and the base background color is opaque. 141 bool hasOpaqueBackground() const; 142 143 Color baseBackgroundColor() const; 144 void setBaseBackgroundColor(const Color&); 145 void updateBackgroundRecursively(const Color&, bool); 146 147 void adjustViewSize(); 148 149 virtual IntRect windowClipRect(IncludeScrollbarsInRect = ExcludeScrollbars) const OVERRIDE; 150 IntRect windowClipRectForFrameOwner(const HTMLFrameOwnerElement*) const; 151 152 virtual IntRect windowResizerRect() const OVERRIDE; 153 154 virtual float visibleContentScaleFactor() const OVERRIDE { return m_visibleContentScaleFactor; } 155 void setVisibleContentScaleFactor(float); 156 157 virtual float inputEventsScaleFactor() const OVERRIDE; 158 virtual IntSize inputEventsOffsetForEmulation() const OVERRIDE; 159 void setInputEventsTransformForEmulation(const IntSize&, float); 160 161 virtual void setScrollPosition(const IntPoint&, ScrollBehavior = ScrollBehaviorInstant) OVERRIDE; 162 virtual bool isRubberBandInProgress() const OVERRIDE; 163 void setScrollPositionNonProgrammatically(const IntPoint&); 164 165 // This is different than visibleContentRect() in that it ignores negative (or overly positive) 166 // offsets from rubber-banding, and it takes zooming into account. 167 LayoutRect viewportConstrainedVisibleContentRect() const; 168 void viewportConstrainedVisibleContentSizeChanged(bool widthChanged, bool heightChanged); 169 170 AtomicString mediaType() const; 171 void setMediaType(const AtomicString&); 172 void adjustMediaTypeForPrinting(bool printing); 173 174 void addSlowRepaintObject(); 175 void removeSlowRepaintObject(); 176 bool hasSlowRepaintObjects() const { return m_slowRepaintObjectCount; } 177 178 // Fixed-position objects. 179 typedef HashSet<RenderObject*> ViewportConstrainedObjectSet; 180 void addViewportConstrainedObject(RenderObject*); 181 void removeViewportConstrainedObject(RenderObject*); 182 const ViewportConstrainedObjectSet* viewportConstrainedObjects() const { return m_viewportConstrainedObjects.get(); } 183 bool hasViewportConstrainedObjects() const { return m_viewportConstrainedObjects && m_viewportConstrainedObjects->size() > 0; } 184 185 void handleLoadCompleted(); 186 187 void updateAnnotatedRegions(); 188 189 void restoreScrollbar(); 190 191 void postLayoutTimerFired(Timer<FrameView>*); 192 193 bool wasScrolledByUser() const; 194 void setWasScrolledByUser(bool); 195 196 bool safeToPropagateScrollToParent() const { return m_safeToPropagateScrollToParent; } 197 void setSafeToPropagateScrollToParent(bool isSafe) { m_safeToPropagateScrollToParent = isSafe; } 198 199 void addWidget(RenderWidget*); 200 void removeWidget(RenderWidget*); 201 void updateWidgetPositions(); 202 203 void addWidgetToUpdate(RenderEmbeddedObject&); 204 205 virtual void paintContents(GraphicsContext*, const IntRect& damageRect) OVERRIDE; 206 void setPaintBehavior(PaintBehavior); 207 PaintBehavior paintBehavior() const; 208 bool isPainting() const; 209 bool hasEverPainted() const { return m_lastPaintTime; } 210 void setNodeToDraw(Node*); 211 212 virtual void paintOverhangAreas(GraphicsContext*, const IntRect& horizontalOverhangArea, const IntRect& verticalOverhangArea, const IntRect& dirtyRect) OVERRIDE; 213 virtual void paintScrollCorner(GraphicsContext*, const IntRect& cornerRect) OVERRIDE; 214 virtual void paintScrollbar(GraphicsContext*, Scrollbar*, const IntRect&) OVERRIDE; 215 216 Color documentBackgroundColor() const; 217 218 static double currentFrameTimeStamp() { return s_currentFrameTimeStamp; } 219 220 void updateLayoutAndStyleForPainting(); 221 void updateLayoutAndStyleIfNeededRecursive(); 222 223 void invalidateTreeIfNeededRecursive(); 224 225 void incrementVisuallyNonEmptyCharacterCount(unsigned); 226 void incrementVisuallyNonEmptyPixelCount(const IntSize&); 227 void setIsVisuallyNonEmpty() { m_isVisuallyNonEmpty = true; } 228 void enableAutoSizeMode(const IntSize& minSize, const IntSize& maxSize); 229 void disableAutoSizeMode() { m_autoSizeInfo.clear(); } 230 231 void forceLayout(bool allowSubtree = false); 232 void forceLayoutForPagination(const FloatSize& pageSize, const FloatSize& originalPageSize, float maximumShrinkFactor); 233 234 bool scrollToFragment(const KURL&); 235 bool scrollToAnchor(const String&); 236 void maintainScrollPositionAtAnchor(Node*); 237 void scrollElementToRect(Element*, const IntRect&); 238 void scrollContentsIfNeededRecursive(); 239 240 // Methods to convert points and rects between the coordinate space of the renderer, and this view. 241 IntRect convertFromRenderer(const RenderObject&, const IntRect&) const; 242 IntRect convertToRenderer(const RenderObject&, const IntRect&) const; 243 IntPoint convertFromRenderer(const RenderObject&, const IntPoint&) const; 244 IntPoint convertToRenderer(const RenderObject&, const IntPoint&) const; 245 246 bool isFrameViewScrollCorner(RenderScrollbarPart* scrollCorner) const { return m_scrollCorner == scrollCorner; } 247 248 enum ScrollingReasons { 249 Scrollable, 250 NotScrollableNoOverflow, 251 NotScrollableNotVisible, 252 NotScrollableExplicitlyDisabled 253 }; 254 255 ScrollingReasons scrollingReasons(); 256 bool isScrollable(); 257 258 enum ScrollbarModesCalculationStrategy { RulesFromWebContentOnly, AnyRule }; 259 void calculateScrollbarModesForLayoutAndSetViewportRenderer(ScrollbarMode& hMode, ScrollbarMode& vMode, ScrollbarModesCalculationStrategy = AnyRule); 260 261 virtual IntPoint lastKnownMousePosition() const OVERRIDE; 262 bool shouldSetCursor() const; 263 264 void setCursor(const Cursor&); 265 266 virtual bool scrollbarsCanBeActive() const OVERRIDE; 267 268 // FIXME: Remove this method once plugin loading is decoupled from layout. 269 void flushAnyPendingPostLayoutTasks(); 270 271 virtual bool shouldSuspendScrollAnimations() const OVERRIDE; 272 virtual void scrollbarStyleChanged() OVERRIDE; 273 274 RenderBox* embeddedContentBox() const; 275 276 void setTracksPaintInvalidations(bool); 277 bool isTrackingPaintInvalidations() const { return m_isTrackingPaintInvalidations; } 278 void resetTrackedPaintInvalidations(); 279 280 String trackedPaintInvalidationRectsAsText() const; 281 282 typedef HashSet<ScrollableArea*> ScrollableAreaSet; 283 void addScrollableArea(ScrollableArea*); 284 void removeScrollableArea(ScrollableArea*); 285 const ScrollableAreaSet* scrollableAreas() const { return m_scrollableAreas.get(); } 286 287 // With CSS style "resize:" enabled, a little resizer handle will appear at the bottom 288 // right of the object. We keep track of these resizer areas for checking if touches 289 // (implemented using Scroll gesture) are targeting the resizer. 290 typedef HashSet<RenderBox*> ResizerAreaSet; 291 void addResizerArea(RenderBox&); 292 void removeResizerArea(RenderBox&); 293 const ResizerAreaSet* resizerAreas() const { return m_resizerAreas.get(); } 294 295 virtual void setParent(Widget*) OVERRIDE; 296 virtual void removeChild(Widget*) OVERRIDE; 297 298 // This function exists for ports that need to handle wheel events manually. 299 // On Mac WebKit1 the underlying NSScrollView just does the scrolling, but on most other platforms 300 // we need this function in order to do the scroll ourselves. 301 bool wheelEvent(const PlatformWheelEvent&); 302 303 bool inProgrammaticScroll() const { return m_inProgrammaticScroll; } 304 void setInProgrammaticScroll(bool programmaticScroll) { m_inProgrammaticScroll = programmaticScroll; } 305 306 virtual bool isActive() const OVERRIDE; 307 308 // DEPRECATED: Use viewportConstrainedVisibleContentRect() instead. 309 IntSize scrollOffsetForFixedPosition() const; 310 311 // Override scrollbar notifications to update the AXObject cache. 312 virtual void didAddScrollbar(Scrollbar*, ScrollbarOrientation) OVERRIDE; 313 virtual void willRemoveScrollbar(Scrollbar*, ScrollbarOrientation) OVERRIDE; 314 315 // FIXME: This should probably be renamed as the 'inSubtreeLayout' parameter 316 // passed around the FrameView layout methods can be true while this returns 317 // false. 318 bool isSubtreeLayout() const { return !!m_layoutSubtreeRoot; } 319 320 // Sets the tickmarks for the FrameView, overriding the default behavior 321 // which is to display the tickmarks corresponding to find results. 322 // If |m_tickmarks| is empty, the default behavior is restored. 323 void setTickmarks(const Vector<IntRect>& tickmarks) { m_tickmarks = tickmarks; } 324 325 // Since the compositor can resize the viewport due to top controls and 326 // commit scroll offsets before a WebView::resize occurs, we need to adjust 327 // our scroll extents to prevent clamping the scroll offsets. 328 void setTopControlsViewportAdjustment(float); 329 330 virtual IntPoint maximumScrollPosition() const OVERRIDE; 331 332 // ScrollableArea interface 333 virtual void invalidateScrollbarRect(Scrollbar*, const IntRect&) OVERRIDE; 334 virtual void getTickmarks(Vector<IntRect>&) const OVERRIDE; 335 virtual void scrollTo(const IntSize&) OVERRIDE; 336 virtual IntRect scrollableAreaBoundingBox() const OVERRIDE; 337 virtual bool scrollAnimatorEnabled() const OVERRIDE; 338 virtual bool usesCompositedScrolling() const OVERRIDE; 339 virtual GraphicsLayer* layerForScrolling() const OVERRIDE; 340 virtual GraphicsLayer* layerForHorizontalScrollbar() const OVERRIDE; 341 virtual GraphicsLayer* layerForVerticalScrollbar() const OVERRIDE; 342 virtual GraphicsLayer* layerForScrollCorner() const OVERRIDE; 343 344 protected: 345 virtual void scrollContentsIfNeeded(); 346 virtual bool scrollContentsFastPath(const IntSize& scrollDelta) OVERRIDE; 347 virtual void scrollContentsSlowPath(const IntRect& updateRect) OVERRIDE; 348 349 virtual bool isVerticalDocument() const OVERRIDE; 350 virtual bool isFlippedDocument() const OVERRIDE; 351 352 // Prevents creation of scrollbars. Used to prevent drawing two sets of 353 // overlay scrollbars in the case of the pinch viewport. 354 virtual bool scrollbarsDisabled() const OVERRIDE; 355 356 private: 357 explicit FrameView(LocalFrame*); 358 359 void reset(); 360 void init(); 361 362 virtual void frameRectsChanged() OVERRIDE; 363 virtual bool isFrameView() const OVERRIDE { return true; } 364 365 friend class RenderWidget; 366 367 bool contentsInCompositedLayer() const; 368 369 void applyOverflowToViewportAndSetRenderer(RenderObject*, ScrollbarMode& hMode, ScrollbarMode& vMode); 370 void updateOverflowStatus(bool horizontalOverflow, bool verticalOverflow); 371 372 void updateCounters(); 373 void forceLayoutParentViewIfNeeded(); 374 void performPreLayoutTasks(); 375 void performLayout(RenderObject* rootForThisLayout, bool inSubtreeLayout); 376 void scheduleOrPerformPostLayoutTasks(); 377 void performPostLayoutTasks(); 378 379 void invalidateTreeIfNeeded(); 380 381 void gatherDebugLayoutRects(RenderObject* layoutRoot); 382 383 DocumentLifecycle& lifecycle() const; 384 385 virtual void contentRectangleForPaintInvalidation(const IntRect&) OVERRIDE; 386 virtual void contentsResized() OVERRIDE; 387 virtual void scrollbarExistenceDidChange() OVERRIDE; 388 389 // Override ScrollView methods to do point conversion via renderers, in order to 390 // take transforms into account. 391 virtual IntRect convertToContainingView(const IntRect&) const OVERRIDE; 392 virtual IntRect convertFromContainingView(const IntRect&) const OVERRIDE; 393 virtual IntPoint convertToContainingView(const IntPoint&) const OVERRIDE; 394 virtual IntPoint convertFromContainingView(const IntPoint&) const OVERRIDE; 395 396 void updateWidgetPositionsIfNeeded(); 397 398 bool wasViewportResized(); 399 void sendResizeEventIfNeeded(); 400 401 void updateScrollableAreaSet(); 402 403 virtual void notifyPageThatContentAreaWillPaint() const OVERRIDE; 404 405 void scheduleUpdateWidgetsIfNecessary(); 406 void updateWidgetsTimerFired(Timer<FrameView>*); 407 bool updateWidgets(); 408 409 void scrollToAnchor(); 410 void scrollPositionChanged(); 411 void didScrollTimerFired(Timer<FrameView>*); 412 413 void updateLayersAndCompositingAfterScrollIfNeeded(); 414 415 static bool computeCompositedSelectionBounds(LocalFrame&, CompositedSelectionBound& start, CompositedSelectionBound& end); 416 void updateFixedElementPaintInvalidationRectsAfterScroll(); 417 void updateCompositedSelectionBoundsIfNeeded(); 418 419 bool hasCustomScrollbars() const; 420 bool shouldUseCustomScrollbars(Element*& customScrollbarElement, LocalFrame*& customScrollbarFrame); 421 422 virtual void updateScrollCorner() OVERRIDE; 423 424 FrameView* parentFrameView() const; 425 426 AXObjectCache* axObjectCache() const; 427 void removeFromAXObjectCache(); 428 429 void setLayoutSizeInternal(const IntSize&); 430 431 bool paintInvalidationIsAllowed() const 432 { 433 return !isInPerformLayout() || canInvalidatePaintDuringPerformLayout(); 434 } 435 436 static double s_currentFrameTimeStamp; // used for detecting decoded resource thrash in the cache 437 static bool s_inPaintContents; 438 439 LayoutSize m_size; 440 441 typedef WillBeHeapHashSet<RefPtrWillBeMember<RenderEmbeddedObject> > EmbeddedObjectSet; 442 WillBePersistentHeapHashSet<RefPtrWillBeMember<RenderEmbeddedObject> > m_widgetUpdateSet; 443 444 // FIXME: These are just "children" of the FrameView and should be RefPtr<Widget> instead. 445 WillBePersistentHeapHashSet<RefPtrWillBeMember<RenderWidget> > m_widgets; 446 447 // Oilpan: the use of a persistent back reference 'emulates' the 448 // RefPtr-cycle that is kept between the two objects non-Oilpan. 449 // 450 // That cycle is broken when a LocalFrame is detached by 451 // FrameLoader::detachFromParent(), it then clears its 452 // FrameView's m_frame reference by calling setView(nullptr). 453 RefPtrWillBePersistent<LocalFrame> m_frame; 454 455 bool m_doFullPaintInvalidation; 456 457 bool m_canHaveScrollbars; 458 unsigned m_slowRepaintObjectCount; 459 460 bool m_hasPendingLayout; 461 RenderObject* m_layoutSubtreeRoot; 462 463 bool m_layoutSchedulingEnabled; 464 bool m_inPerformLayout; 465 bool m_canInvalidatePaintDuringPerformLayout; 466 bool m_inSynchronousPostLayout; 467 int m_layoutCount; 468 unsigned m_nestedLayoutCount; 469 Timer<FrameView> m_postLayoutTasksTimer; 470 Timer<FrameView> m_updateWidgetsTimer; 471 bool m_firstLayoutCallbackPending; 472 473 bool m_firstLayout; 474 bool m_isTransparent; 475 Color m_baseBackgroundColor; 476 IntSize m_lastViewportSize; 477 float m_lastZoomFactor; 478 479 AtomicString m_mediaType; 480 AtomicString m_mediaTypeWhenNotPrinting; 481 482 bool m_overflowStatusDirty; 483 bool m_horizontalOverflow; 484 bool m_verticalOverflow; 485 RenderObject* m_viewportRenderer; 486 487 bool m_wasScrolledByUser; 488 bool m_inProgrammaticScroll; 489 bool m_safeToPropagateScrollToParent; 490 491 double m_lastPaintTime; 492 493 bool m_isTrackingPaintInvalidations; // Used for testing. 494 Vector<IntRect> m_trackedPaintInvalidationRects; 495 496 RefPtrWillBePersistent<Node> m_nodeToDraw; 497 PaintBehavior m_paintBehavior; 498 bool m_isPainting; 499 500 unsigned m_visuallyNonEmptyCharacterCount; 501 unsigned m_visuallyNonEmptyPixelCount; 502 bool m_isVisuallyNonEmpty; 503 bool m_firstVisuallyNonEmptyLayoutCallbackPending; 504 505 RefPtrWillBePersistent<Node> m_maintainScrollPositionAnchor; 506 507 // Renderer to hold our custom scroll corner. 508 RawPtrWillBePersistent<RenderScrollbarPart> m_scrollCorner; 509 510 OwnPtr<ScrollableAreaSet> m_scrollableAreas; 511 OwnPtr<ResizerAreaSet> m_resizerAreas; 512 OwnPtr<ViewportConstrainedObjectSet> m_viewportConstrainedObjects; 513 OwnPtr<FrameViewAutoSizeInfo> m_autoSizeInfo; 514 515 float m_visibleContentScaleFactor; 516 IntSize m_inputEventsOffsetForEmulation; 517 float m_inputEventsScaleFactorForEmulation; 518 519 IntSize m_layoutSize; 520 bool m_layoutSizeFixedToFrameSize; 521 522 Timer<FrameView> m_didScrollTimer; 523 524 Vector<IntRect> m_tickmarks; 525 526 bool m_needsUpdateWidgetPositions; 527 float m_topControlsViewportAdjustment; 528 }; 529 530 inline void FrameView::incrementVisuallyNonEmptyCharacterCount(unsigned count) 531 { 532 if (m_isVisuallyNonEmpty) 533 return; 534 m_visuallyNonEmptyCharacterCount += count; 535 // Use a threshold value to prevent very small amounts of visible content from triggering didFirstVisuallyNonEmptyLayout. 536 // The first few hundred characters rarely contain the interesting content of the page. 537 static const unsigned visualCharacterThreshold = 200; 538 if (m_visuallyNonEmptyCharacterCount > visualCharacterThreshold) 539 setIsVisuallyNonEmpty(); 540 } 541 542 inline void FrameView::incrementVisuallyNonEmptyPixelCount(const IntSize& size) 543 { 544 if (m_isVisuallyNonEmpty) 545 return; 546 m_visuallyNonEmptyPixelCount += size.width() * size.height(); 547 // Use a threshold value to prevent very small amounts of visible content from triggering didFirstVisuallyNonEmptyLayout 548 static const unsigned visualPixelThreshold = 32 * 32; 549 if (m_visuallyNonEmptyPixelCount > visualPixelThreshold) 550 setIsVisuallyNonEmpty(); 551 } 552 553 DEFINE_TYPE_CASTS(FrameView, Widget, widget, widget->isFrameView(), widget.isFrameView()); 554 555 class AllowPaintInvalidationScope { 556 public: 557 explicit AllowPaintInvalidationScope(FrameView* view) 558 : m_view(view) 559 , m_originalValue(view ? view->canInvalidatePaintDuringPerformLayout() : false) 560 { 561 if (!m_view) 562 return; 563 564 m_view->setCanInvalidatePaintDuringPerformLayout(true); 565 } 566 567 ~AllowPaintInvalidationScope() 568 { 569 if (!m_view) 570 return; 571 572 m_view->setCanInvalidatePaintDuringPerformLayout(m_originalValue); 573 } 574 private: 575 FrameView* m_view; 576 bool m_originalValue; 577 }; 578 579 } // namespace blink 580 581 #endif // FrameView_h 582