зеркало из https://github.com/mozilla/gecko-dev.git
394 строки
13 KiB
C++
394 строки
13 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=2 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
/**
|
|
* compute sticky positioning, both during reflow and when the scrolling
|
|
* container scrolls
|
|
*/
|
|
|
|
#include "StickyScrollContainer.h"
|
|
#include "nsIFrame.h"
|
|
#include "nsIScrollableFrame.h"
|
|
#include "nsLayoutUtils.h"
|
|
#include "RestyleTracker.h"
|
|
|
|
using namespace mozilla::css;
|
|
|
|
namespace mozilla {
|
|
|
|
void DestroyStickyScrollContainer(void* aPropertyValue)
|
|
{
|
|
delete static_cast<StickyScrollContainer*>(aPropertyValue);
|
|
}
|
|
|
|
NS_DECLARE_FRAME_PROPERTY(StickyScrollContainerProperty,
|
|
DestroyStickyScrollContainer)
|
|
|
|
StickyScrollContainer::StickyScrollContainer(nsIScrollableFrame* aScrollFrame)
|
|
: mScrollFrame(aScrollFrame)
|
|
, mScrollPosition()
|
|
{
|
|
mScrollFrame->AddScrollPositionListener(this);
|
|
}
|
|
|
|
StickyScrollContainer::~StickyScrollContainer()
|
|
{
|
|
mScrollFrame->RemoveScrollPositionListener(this);
|
|
}
|
|
|
|
// static
|
|
StickyScrollContainer*
|
|
StickyScrollContainer::GetStickyScrollContainerForFrame(nsIFrame* aFrame)
|
|
{
|
|
nsIScrollableFrame* scrollFrame =
|
|
nsLayoutUtils::GetNearestScrollableFrame(aFrame->GetParent(),
|
|
nsLayoutUtils::SCROLLABLE_SAME_DOC |
|
|
nsLayoutUtils::SCROLLABLE_INCLUDE_HIDDEN);
|
|
if (!scrollFrame) {
|
|
// We might not find any, for instance in the case of
|
|
// <html style="position: fixed">
|
|
return nullptr;
|
|
}
|
|
FrameProperties props = static_cast<nsIFrame*>(do_QueryFrame(scrollFrame))->
|
|
Properties();
|
|
StickyScrollContainer* s = static_cast<StickyScrollContainer*>
|
|
(props.Get(StickyScrollContainerProperty()));
|
|
if (!s) {
|
|
s = new StickyScrollContainer(scrollFrame);
|
|
props.Set(StickyScrollContainerProperty(), s);
|
|
}
|
|
return s;
|
|
}
|
|
|
|
// static
|
|
void
|
|
StickyScrollContainer::NotifyReparentedFrameAcrossScrollFrameBoundary(nsIFrame* aFrame,
|
|
nsIFrame* aOldParent)
|
|
{
|
|
nsIScrollableFrame* oldScrollFrame =
|
|
nsLayoutUtils::GetNearestScrollableFrame(aOldParent,
|
|
nsLayoutUtils::SCROLLABLE_SAME_DOC |
|
|
nsLayoutUtils::SCROLLABLE_INCLUDE_HIDDEN);
|
|
if (!oldScrollFrame) {
|
|
// XXX maybe aFrame has sticky descendants that can be sticky now, but
|
|
// we aren't going to handle that.
|
|
return;
|
|
}
|
|
FrameProperties props = static_cast<nsIFrame*>(do_QueryFrame(oldScrollFrame))->
|
|
Properties();
|
|
StickyScrollContainer* oldSSC = static_cast<StickyScrollContainer*>
|
|
(props.Get(StickyScrollContainerProperty()));
|
|
if (!oldSSC) {
|
|
// aOldParent had no sticky descendants, so aFrame doesn't have any sticky
|
|
// descendants, and we're done here.
|
|
return;
|
|
}
|
|
|
|
auto i = oldSSC->mFrames.Length();
|
|
while (i-- > 0) {
|
|
nsIFrame* f = oldSSC->mFrames[i];
|
|
StickyScrollContainer* newSSC = GetStickyScrollContainerForFrame(f);
|
|
if (newSSC != oldSSC) {
|
|
oldSSC->RemoveFrame(f);
|
|
if (newSSC) {
|
|
newSSC->AddFrame(f);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// static
|
|
StickyScrollContainer*
|
|
StickyScrollContainer::GetStickyScrollContainerForScrollFrame(nsIFrame* aFrame)
|
|
{
|
|
FrameProperties props = aFrame->Properties();
|
|
return static_cast<StickyScrollContainer*>
|
|
(props.Get(StickyScrollContainerProperty()));
|
|
}
|
|
|
|
static nscoord
|
|
ComputeStickySideOffset(Side aSide, const nsStyleSides& aOffset,
|
|
nscoord aPercentBasis)
|
|
{
|
|
if (eStyleUnit_Auto == aOffset.GetUnit(aSide)) {
|
|
return NS_AUTOOFFSET;
|
|
} else {
|
|
return nsLayoutUtils::ComputeCBDependentValue(aPercentBasis,
|
|
aOffset.Get(aSide));
|
|
}
|
|
}
|
|
|
|
// static
|
|
void
|
|
StickyScrollContainer::ComputeStickyOffsets(nsIFrame* aFrame)
|
|
{
|
|
nsIScrollableFrame* scrollableFrame =
|
|
nsLayoutUtils::GetNearestScrollableFrame(aFrame->GetParent(),
|
|
nsLayoutUtils::SCROLLABLE_SAME_DOC |
|
|
nsLayoutUtils::SCROLLABLE_INCLUDE_HIDDEN);
|
|
|
|
if (!scrollableFrame) {
|
|
// Bail.
|
|
return;
|
|
}
|
|
|
|
nsSize scrollContainerSize = scrollableFrame->GetScrolledFrame()->
|
|
GetContentRectRelativeToSelf().Size();
|
|
|
|
nsMargin computedOffsets;
|
|
const nsStylePosition* position = aFrame->StylePosition();
|
|
|
|
computedOffsets.left = ComputeStickySideOffset(eSideLeft, position->mOffset,
|
|
scrollContainerSize.width);
|
|
computedOffsets.right = ComputeStickySideOffset(eSideRight, position->mOffset,
|
|
scrollContainerSize.width);
|
|
computedOffsets.top = ComputeStickySideOffset(eSideTop, position->mOffset,
|
|
scrollContainerSize.height);
|
|
computedOffsets.bottom = ComputeStickySideOffset(eSideBottom, position->mOffset,
|
|
scrollContainerSize.height);
|
|
|
|
// Store the offset
|
|
FrameProperties props = aFrame->Properties();
|
|
nsMargin* offsets = static_cast<nsMargin*>
|
|
(props.Get(nsIFrame::ComputedOffsetProperty()));
|
|
if (offsets) {
|
|
*offsets = computedOffsets;
|
|
} else {
|
|
props.Set(nsIFrame::ComputedOffsetProperty(),
|
|
new nsMargin(computedOffsets));
|
|
}
|
|
}
|
|
|
|
void
|
|
StickyScrollContainer::ComputeStickyLimits(nsIFrame* aFrame, nsRect* aStick,
|
|
nsRect* aContain) const
|
|
{
|
|
NS_ASSERTION(nsLayoutUtils::IsFirstContinuationOrSpecialSibling(aFrame),
|
|
"Can't sticky position individual continuations");
|
|
|
|
aStick->SetRect(nscoord_MIN/2, nscoord_MIN/2, nscoord_MAX, nscoord_MAX);
|
|
aContain->SetRect(nscoord_MIN/2, nscoord_MIN/2, nscoord_MAX, nscoord_MAX);
|
|
|
|
const nsMargin* computedOffsets = static_cast<nsMargin*>(
|
|
aFrame->Properties().Get(nsIFrame::ComputedOffsetProperty()));
|
|
if (!computedOffsets) {
|
|
// We haven't reflowed the scroll frame yet, so offsets haven't been
|
|
// computed. Bail.
|
|
return;
|
|
}
|
|
|
|
nsIFrame* scrolledFrame = mScrollFrame->GetScrolledFrame();
|
|
// FIXME (Bug 920688): cbFrame isn't quite right if we're dealing
|
|
// with a block-in-inline split whose first part is a block. We
|
|
// probably want the first in flow of the containing block of the
|
|
// first inline part. (Or maybe those block-in-inline split pieces
|
|
// are never a containing block, and we're ok?)
|
|
nsIFrame* cbFrame = aFrame->GetContainingBlock();
|
|
NS_ASSERTION(cbFrame == scrolledFrame ||
|
|
nsLayoutUtils::IsProperAncestorFrame(scrolledFrame, cbFrame),
|
|
"Scroll frame should be an ancestor of the containing block");
|
|
|
|
nsRect rect =
|
|
nsLayoutUtils::GetAllInFlowRectsUnion(aFrame, aFrame->GetParent());
|
|
|
|
// Containing block limits for the position of aFrame relative to its parent.
|
|
// The margin box of the sticky element stays within the content box of the
|
|
// contaning-block element.
|
|
if (cbFrame != scrolledFrame) {
|
|
*aContain = nsLayoutUtils::
|
|
GetAllInFlowRectsUnion(cbFrame, aFrame->GetParent(),
|
|
nsLayoutUtils::RECTS_USE_CONTENT_BOX);
|
|
nsRect marginRect = nsLayoutUtils::
|
|
GetAllInFlowRectsUnion(aFrame, aFrame->GetParent(),
|
|
nsLayoutUtils::RECTS_USE_MARGIN_BOX);
|
|
|
|
// Deflate aContain by the difference between the union of aFrame's
|
|
// continuations' margin boxes and the union of their border boxes, so that
|
|
// by keeping aFrame within aContain, we keep the union of the margin boxes
|
|
// within the containing block's content box.
|
|
aContain->Deflate(marginRect - rect);
|
|
|
|
// Deflate aContain by the border-box size, to form a constraint on the
|
|
// upper-left corner of aFrame and continuations.
|
|
aContain->Deflate(nsMargin(0, rect.width, rect.height, 0));
|
|
}
|
|
|
|
nsMargin sfPadding = scrolledFrame->GetUsedPadding();
|
|
nsPoint sfOffset = aFrame->GetParent()->GetOffsetTo(scrolledFrame);
|
|
|
|
// Top
|
|
if (computedOffsets->top != NS_AUTOOFFSET) {
|
|
aStick->SetTopEdge(mScrollPosition.y + sfPadding.top +
|
|
computedOffsets->top - sfOffset.y);
|
|
}
|
|
|
|
nsSize sfSize = scrolledFrame->GetContentRectRelativeToSelf().Size();
|
|
|
|
// Bottom
|
|
if (computedOffsets->bottom != NS_AUTOOFFSET &&
|
|
(computedOffsets->top == NS_AUTOOFFSET ||
|
|
rect.height <= sfSize.height - computedOffsets->TopBottom())) {
|
|
aStick->SetBottomEdge(mScrollPosition.y + sfPadding.top + sfSize.height -
|
|
computedOffsets->bottom - rect.height - sfOffset.y);
|
|
}
|
|
|
|
uint8_t direction = cbFrame->StyleVisibility()->mDirection;
|
|
|
|
// Left
|
|
if (computedOffsets->left != NS_AUTOOFFSET &&
|
|
(computedOffsets->right == NS_AUTOOFFSET ||
|
|
direction == NS_STYLE_DIRECTION_LTR ||
|
|
rect.width <= sfSize.width - computedOffsets->LeftRight())) {
|
|
aStick->SetLeftEdge(mScrollPosition.x + sfPadding.left +
|
|
computedOffsets->left - sfOffset.x);
|
|
}
|
|
|
|
// Right
|
|
if (computedOffsets->right != NS_AUTOOFFSET &&
|
|
(computedOffsets->left == NS_AUTOOFFSET ||
|
|
direction == NS_STYLE_DIRECTION_RTL ||
|
|
rect.width <= sfSize.width - computedOffsets->LeftRight())) {
|
|
aStick->SetRightEdge(mScrollPosition.x + sfPadding.left + sfSize.width -
|
|
computedOffsets->right - rect.width - sfOffset.x);
|
|
}
|
|
|
|
// These limits are for the bounding box of aFrame's continuations. Convert
|
|
// to limits for aFrame itself.
|
|
nsPoint frameOffset = aFrame->GetPosition() - rect.TopLeft();
|
|
aStick->MoveBy(frameOffset);
|
|
aContain->MoveBy(frameOffset);
|
|
}
|
|
|
|
nsPoint
|
|
StickyScrollContainer::ComputePosition(nsIFrame* aFrame) const
|
|
{
|
|
nsRect stick;
|
|
nsRect contain;
|
|
ComputeStickyLimits(aFrame, &stick, &contain);
|
|
|
|
nsPoint position = aFrame->GetNormalPosition();
|
|
|
|
// For each sticky direction (top, bottom, left, right), move the frame along
|
|
// the appropriate axis, based on the scroll position, but limit this to keep
|
|
// the element's margin box within the containing block.
|
|
position.y = std::max(position.y, std::min(stick.y, contain.YMost()));
|
|
position.y = std::min(position.y, std::max(stick.YMost(), contain.y));
|
|
position.x = std::max(position.x, std::min(stick.x, contain.XMost()));
|
|
position.x = std::min(position.x, std::max(stick.XMost(), contain.x));
|
|
|
|
return position;
|
|
}
|
|
|
|
void
|
|
StickyScrollContainer::GetScrollRanges(nsIFrame* aFrame, nsRect* aOuter,
|
|
nsRect* aInner) const
|
|
{
|
|
// We need to use the first in flow; ComputeStickyLimits requires
|
|
// this, at the very least because its call to
|
|
// nsLayoutUtils::GetAllInFlowRectsUnion requires it.
|
|
nsIFrame *firstCont =
|
|
nsLayoutUtils::FirstContinuationOrSpecialSibling(aFrame);
|
|
|
|
nsRect stick;
|
|
nsRect contain;
|
|
ComputeStickyLimits(firstCont, &stick, &contain);
|
|
|
|
aOuter->SetRect(nscoord_MIN/2, nscoord_MIN/2, nscoord_MAX, nscoord_MAX);
|
|
aInner->SetRect(nscoord_MIN/2, nscoord_MIN/2, nscoord_MAX, nscoord_MAX);
|
|
|
|
const nsPoint normalPosition = aFrame->GetNormalPosition();
|
|
|
|
// Bottom and top
|
|
if (stick.YMost() != nscoord_MAX/2) {
|
|
aOuter->SetTopEdge(contain.y - stick.YMost());
|
|
aInner->SetTopEdge(normalPosition.y - stick.YMost());
|
|
}
|
|
|
|
if (stick.y != nscoord_MIN/2) {
|
|
aInner->SetBottomEdge(normalPosition.y - stick.y);
|
|
aOuter->SetBottomEdge(contain.YMost() - stick.y);
|
|
}
|
|
|
|
// Right and left
|
|
if (stick.XMost() != nscoord_MAX/2) {
|
|
aOuter->SetLeftEdge(contain.x - stick.XMost());
|
|
aInner->SetLeftEdge(normalPosition.x - stick.XMost());
|
|
}
|
|
|
|
if (stick.x != nscoord_MIN/2) {
|
|
aInner->SetRightEdge(normalPosition.x - stick.x);
|
|
aOuter->SetRightEdge(contain.XMost() - stick.x);
|
|
}
|
|
}
|
|
|
|
void
|
|
StickyScrollContainer::PositionContinuations(nsIFrame* aFrame)
|
|
{
|
|
NS_ASSERTION(nsLayoutUtils::IsFirstContinuationOrSpecialSibling(aFrame),
|
|
"Should be starting from the first continuation");
|
|
nsPoint translation = ComputePosition(aFrame) - aFrame->GetPosition();
|
|
|
|
// Move all continuation frames by the same amount.
|
|
for (nsIFrame* cont = aFrame; cont;
|
|
cont = nsLayoutUtils::GetNextContinuationOrSpecialSibling(cont)) {
|
|
cont->SetPosition(cont->GetPosition() + translation);
|
|
}
|
|
}
|
|
|
|
void
|
|
StickyScrollContainer::UpdatePositions(nsPoint aScrollPosition,
|
|
nsIFrame* aSubtreeRoot)
|
|
{
|
|
#ifdef DEBUG
|
|
{
|
|
nsIFrame* scrollFrameAsFrame = do_QueryFrame(mScrollFrame);
|
|
NS_ASSERTION(!aSubtreeRoot || aSubtreeRoot == scrollFrameAsFrame,
|
|
"If reflowing, should be reflowing the scroll frame");
|
|
}
|
|
#endif
|
|
mScrollPosition = aScrollPosition;
|
|
|
|
OverflowChangedTracker oct;
|
|
oct.SetSubtreeRoot(aSubtreeRoot);
|
|
for (nsTArray<nsIFrame*>::size_type i = 0; i < mFrames.Length(); i++) {
|
|
nsIFrame* f = mFrames[i];
|
|
if (!nsLayoutUtils::IsFirstContinuationOrSpecialSibling(f)) {
|
|
// This frame was added in nsFrame::Init before we knew it wasn't
|
|
// the first special-sibling.
|
|
mFrames.RemoveElementAt(i);
|
|
--i;
|
|
continue;
|
|
}
|
|
|
|
if (aSubtreeRoot) {
|
|
// Reflowing the scroll frame, so recompute offsets.
|
|
ComputeStickyOffsets(f);
|
|
}
|
|
// mFrames will only contain first continuations, because we filter in
|
|
// nsIFrame::Init.
|
|
PositionContinuations(f);
|
|
|
|
for (nsIFrame* cont = f; cont;
|
|
cont = nsLayoutUtils::GetNextContinuationOrSpecialSibling(cont)) {
|
|
oct.AddFrame(cont);
|
|
}
|
|
}
|
|
oct.Flush();
|
|
}
|
|
|
|
void
|
|
StickyScrollContainer::ScrollPositionWillChange(nscoord aX, nscoord aY)
|
|
{
|
|
}
|
|
|
|
void
|
|
StickyScrollContainer::ScrollPositionDidChange(nscoord aX, nscoord aY)
|
|
{
|
|
UpdatePositions(nsPoint(aX, aY), nullptr);
|
|
}
|
|
|
|
} // namespace mozilla
|