| // Copyright 2014 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "core/layout/LayoutMultiColumnSpannerPlaceholder.h" |
| |
| #include "core/layout/LayoutMultiColumnFlowThread.h" |
| |
| namespace blink { |
| |
| static void CopyMarginProperties(ComputedStyle& placeholder_style, |
| const ComputedStyle& spanner_style) { |
| // We really only need the block direction margins, but there are no setters |
| // for that in ComputedStyle. Just copy all margin sides. The inline ones |
| // don't matter anyway. |
| placeholder_style.SetMarginLeft(spanner_style.MarginLeft()); |
| placeholder_style.SetMarginRight(spanner_style.MarginRight()); |
| placeholder_style.SetMarginTop(spanner_style.MarginTop()); |
| placeholder_style.SetMarginBottom(spanner_style.MarginBottom()); |
| } |
| |
| LayoutMultiColumnSpannerPlaceholder* |
| LayoutMultiColumnSpannerPlaceholder::CreateAnonymous( |
| const ComputedStyle& parent_style, |
| LayoutBox& layout_object_in_flow_thread) { |
| LayoutMultiColumnSpannerPlaceholder* new_spanner = |
| new LayoutMultiColumnSpannerPlaceholder(&layout_object_in_flow_thread); |
| Document& document = layout_object_in_flow_thread.GetDocument(); |
| new_spanner->SetDocumentForAnonymous(&document); |
| RefPtr<ComputedStyle> new_style = |
| ComputedStyle::CreateAnonymousStyleWithDisplay(parent_style, |
| EDisplay::kBlock); |
| CopyMarginProperties(*new_style, layout_object_in_flow_thread.StyleRef()); |
| new_spanner->SetStyle(new_style); |
| return new_spanner; |
| } |
| |
| LayoutMultiColumnSpannerPlaceholder::LayoutMultiColumnSpannerPlaceholder( |
| LayoutBox* layout_object_in_flow_thread) |
| : LayoutBox(nullptr), |
| layout_object_in_flow_thread_(layout_object_in_flow_thread) {} |
| |
| void LayoutMultiColumnSpannerPlaceholder:: |
| LayoutObjectInFlowThreadStyleDidChange(const ComputedStyle* old_style) { |
| LayoutBox* object_in_flow_thread = layout_object_in_flow_thread_; |
| if (FlowThread()->RemoveSpannerPlaceholderIfNoLongerValid( |
| object_in_flow_thread)) { |
| // No longer a valid spanner, due to style changes. |this| is now dead. |
| if (object_in_flow_thread->Style()->HasOutOfFlowPosition() && |
| !old_style->HasOutOfFlowPosition()) { |
| // We went from being a spanner to being out-of-flow positioned. When an |
| // object becomes out-of-flow positioned, we need to lay out its parent, |
| // since that's where the now-out-of-flow object gets added to the right |
| // containing block for out-of-flow positioned objects. Since neither a |
| // spanner nor an out-of-flow object is guaranteed to have this parent in |
| // its containing block chain, we need to mark it here, or we risk that |
| // the object isn't laid out. |
| object_in_flow_thread->Parent()->SetNeedsLayout( |
| LayoutInvalidationReason::kColumnsChanged); |
| } |
| return; |
| } |
| UpdateMarginProperties(); |
| } |
| |
| void LayoutMultiColumnSpannerPlaceholder::UpdateMarginProperties() { |
| RefPtr<ComputedStyle> new_style = ComputedStyle::Clone(StyleRef()); |
| CopyMarginProperties(*new_style, layout_object_in_flow_thread_->StyleRef()); |
| SetStyle(new_style); |
| } |
| |
| void LayoutMultiColumnSpannerPlaceholder::InsertedIntoTree() { |
| LayoutBox::InsertedIntoTree(); |
| // The object may previously have been laid out as a non-spanner, but since |
| // it's a spanner now, it needs to be relaid out. |
| layout_object_in_flow_thread_->SetNeedsLayoutAndPrefWidthsRecalc( |
| LayoutInvalidationReason::kColumnsChanged); |
| } |
| |
| void LayoutMultiColumnSpannerPlaceholder::WillBeRemovedFromTree() { |
| if (layout_object_in_flow_thread_) { |
| LayoutBox* ex_spanner = layout_object_in_flow_thread_; |
| layout_object_in_flow_thread_->ClearSpannerPlaceholder(); |
| // Even if the placeholder is going away, the object in the flow thread |
| // might live on. Since it's not a spanner anymore, it needs to be relaid |
| // out. |
| ex_spanner->SetNeedsLayoutAndPrefWidthsRecalc( |
| LayoutInvalidationReason::kColumnsChanged); |
| } |
| LayoutBox::WillBeRemovedFromTree(); |
| } |
| |
| bool LayoutMultiColumnSpannerPlaceholder::NeedsPreferredWidthsRecalculation() |
| const { |
| return layout_object_in_flow_thread_->NeedsPreferredWidthsRecalculation(); |
| } |
| |
| LayoutUnit LayoutMultiColumnSpannerPlaceholder::MinPreferredLogicalWidth() |
| const { |
| return layout_object_in_flow_thread_->MinPreferredLogicalWidth(); |
| } |
| |
| LayoutUnit LayoutMultiColumnSpannerPlaceholder::MaxPreferredLogicalWidth() |
| const { |
| return layout_object_in_flow_thread_->MaxPreferredLogicalWidth(); |
| } |
| |
| void LayoutMultiColumnSpannerPlaceholder::UpdateLayout() { |
| DCHECK(NeedsLayout()); |
| |
| // The placeholder, like any other block level object, has its logical top |
| // calculated and set before layout. Copy this to the actual column-span:all |
| // object before laying it out, so that it gets paginated correctly, in case |
| // we have an enclosing fragmentation context. |
| layout_object_in_flow_thread_->SetLogicalTop(LogicalTop()); |
| |
| // Lay out the actual column-span:all element. |
| layout_object_in_flow_thread_->LayoutIfNeeded(); |
| |
| // The spanner has now been laid out, so its height is known. Time to update |
| // the placeholder's height as well, so that we take up the correct amount of |
| // space in the multicol container. |
| UpdateLogicalHeight(); |
| |
| // Take the overflow from the spanner, so that it gets propagated to the |
| // multicol container and beyond. |
| overflow_.reset(); |
| AddContentsVisualOverflow( |
| layout_object_in_flow_thread_->VisualOverflowRect()); |
| AddLayoutOverflow(layout_object_in_flow_thread_->LayoutOverflowRect()); |
| |
| ClearNeedsLayout(); |
| } |
| |
| void LayoutMultiColumnSpannerPlaceholder::ComputeLogicalHeight( |
| LayoutUnit, |
| LayoutUnit logical_top, |
| LogicalExtentComputedValues& computed_values) const { |
| computed_values.extent_ = layout_object_in_flow_thread_->LogicalHeight(); |
| computed_values.position_ = logical_top; |
| computed_values.margins_.before_ = MarginBefore(); |
| computed_values.margins_.after_ = MarginAfter(); |
| } |
| |
| void LayoutMultiColumnSpannerPlaceholder::Paint( |
| const PaintInfo& paint_info, |
| const LayoutPoint& paint_offset) const { |
| if (!layout_object_in_flow_thread_->HasSelfPaintingLayer()) |
| layout_object_in_flow_thread_->Paint(paint_info, paint_offset); |
| } |
| |
| bool LayoutMultiColumnSpannerPlaceholder::NodeAtPoint( |
| HitTestResult& result, |
| const HitTestLocation& location_in_container, |
| const LayoutPoint& accumulated_offset, |
| HitTestAction action) { |
| return !layout_object_in_flow_thread_->HasSelfPaintingLayer() && |
| layout_object_in_flow_thread_->NodeAtPoint( |
| result, location_in_container, accumulated_offset, action); |
| } |
| |
| } // namespace blink |