pjs/layout/base/nsLayoutUtils.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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*
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*
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*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
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* the Initial Developer. All Rights Reserved.
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*
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#include "nsLayoutUtils.h"
#include "nsIFrame.h"
#include "nsPresContext.h"
#include "nsIContent.h"
#include "nsFrameList.h"
#include "nsLayoutAtoms.h"
#include "nsIAtom.h"
#include "nsCSSPseudoElements.h"
#include "nsIView.h"
#include "nsIScrollableView.h"
#include "nsPlaceholderFrame.h"
#include "nsIScrollableFrame.h"
#include "nsCSSFrameConstructor.h"
#include "nsIPrivateDOMEvent.h"
#include "nsIDOMEvent.h"
#include "nsGUIEvent.h"
/**
* A namespace class for static layout utilities.
*/
/**
* GetFirstChildFrame returns the first "real" child frame of a
* given frame. It will descend down into pseudo-frames (unless the
* pseudo-frame is the :before generated frame).
* @param aFrame the frame
* @param aFrame the frame's content node
*/
static nsIFrame*
GetFirstChildFrame(nsIFrame* aFrame,
nsIContent* aContent)
{
NS_PRECONDITION(aFrame, "NULL frame pointer");
// Get the first child frame
nsIFrame* childFrame = aFrame->GetFirstChild(nsnull);
// If the child frame is a pseudo-frame, then return its first child.
// Note that the frame we create for the generated content is also a
// pseudo-frame and so don't drill down in that case
if (childFrame &&
childFrame->IsPseudoFrame(aContent) &&
!childFrame->IsGeneratedContentFrame()) {
return GetFirstChildFrame(childFrame, aContent);
}
return childFrame;
}
/**
* GetLastChildFrame returns the last "real" child frame of a
* given frame. It will descend down into pseudo-frames (unless the
* pseudo-frame is the :after generated frame).
* @param aFrame the frame
* @param aFrame the frame's content node
*/
static nsIFrame*
GetLastChildFrame(nsIFrame* aFrame,
nsIContent* aContent)
{
NS_PRECONDITION(aFrame, "NULL frame pointer");
// Get the last in flow frame
nsIFrame* lastInFlow = aFrame->GetLastInFlow();
// Get the last child frame
nsIFrame* firstChildFrame = lastInFlow->GetFirstChild(nsnull);
if (firstChildFrame) {
nsFrameList frameList(firstChildFrame);
nsIFrame* lastChildFrame = frameList.LastChild();
NS_ASSERTION(lastChildFrame, "unexpected error");
// Get the frame's first-in-flow. This matters in case the frame has
// been continuted across multiple lines
lastChildFrame = lastChildFrame->GetFirstInFlow();
// If the last child frame is a pseudo-frame, then return its last child.
// Note that the frame we create for the generated content is also a
// pseudo-frame and so don't drill down in that case
if (lastChildFrame &&
lastChildFrame->IsPseudoFrame(aContent) &&
!lastChildFrame->IsGeneratedContentFrame()) {
return GetLastChildFrame(lastChildFrame, aContent);
}
return lastChildFrame;
}
return nsnull;
}
// static
nsIFrame*
nsLayoutUtils::GetBeforeFrame(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "NULL frame pointer");
NS_ASSERTION(!aFrame->GetPrevInFlow(), "aFrame must be first-in-flow");
nsIFrame* firstFrame = GetFirstChildFrame(aFrame, aFrame->GetContent());
if (firstFrame && IsGeneratedContentFor(nsnull, firstFrame,
nsCSSPseudoElements::before)) {
return firstFrame;
}
return nsnull;
}
// static
nsIFrame*
nsLayoutUtils::GetAfterFrame(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "NULL frame pointer");
nsIFrame* lastFrame = GetLastChildFrame(aFrame, aFrame->GetContent());
if (lastFrame && IsGeneratedContentFor(nsnull, lastFrame,
nsCSSPseudoElements::after)) {
return lastFrame;
}
return nsnull;
}
// static
nsIFrame*
nsLayoutUtils::GetPageFrame(nsIFrame* aFrame)
{
for (nsIFrame* frame = aFrame; frame; frame = frame->GetParent()) {
if (frame->GetType() == nsLayoutAtoms::pageFrame) {
return frame;
}
}
return nsnull;
}
nsIFrame*
nsLayoutUtils::GetFloatFromPlaceholder(nsIFrame* aFrame) {
if (nsLayoutAtoms::placeholderFrame != aFrame->GetType()) {
return nsnull;
}
nsIFrame *outOfFlowFrame =
nsPlaceholderFrame::GetRealFrameForPlaceholder(aFrame);
if (outOfFlowFrame->GetStyleDisplay()->IsFloating()) {
return outOfFlowFrame;
}
return nsnull;
}
// static
PRBool
nsLayoutUtils::IsGeneratedContentFor(nsIContent* aContent,
nsIFrame* aFrame,
nsIAtom* aPseudoElement)
{
NS_PRECONDITION(aFrame, "Must have a frame");
NS_PRECONDITION(aPseudoElement, "Must have a pseudo name");
if (!aFrame->IsGeneratedContentFrame()) {
return PR_FALSE;
}
if (aContent && aFrame->GetContent() != aContent) {
return PR_FALSE;
}
return aFrame->GetStyleContext()->GetPseudoType() == aPseudoElement;
}
// static
PRBool
nsLayoutUtils::IsProperAncestorFrame(nsIFrame* aAncestorFrame, nsIFrame* aFrame,
nsIFrame* aCommonAncestor)
{
if (aFrame == aCommonAncestor) {
return PR_FALSE;
}
nsIFrame* parentFrame = aFrame->GetParent();
while (parentFrame != aCommonAncestor) {
if (parentFrame == aAncestorFrame) {
return PR_TRUE;
}
parentFrame = parentFrame->GetParent();
}
return PR_FALSE;
}
// static
PRInt32
nsLayoutUtils::DoCompareTreePosition(nsIContent* aContent1,
nsIContent* aContent2,
PRInt32 aIf1Ancestor,
PRInt32 aIf2Ancestor,
nsIContent* aCommonAncestor)
{
NS_PRECONDITION(aContent1, "aContent1 must not be null");
NS_PRECONDITION(aContent2, "aContent2 must not be null");
nsAutoVoidArray content1Ancestors;
nsIContent* c1;
for (c1 = aContent1; c1 && c1 != aCommonAncestor; c1 = c1->GetParent()) {
content1Ancestors.AppendElement(c1);
}
if (!c1 && aCommonAncestor) {
// So, it turns out aCommonAncestor was not an ancestor of c1. Oops.
// Never mind. We can continue as if aCommonAncestor was null.
aCommonAncestor = nsnull;
}
nsAutoVoidArray content2Ancestors;
nsIContent* c2;
for (c2 = aContent2; c2 && c2 != aCommonAncestor; c2 = c2->GetParent()) {
content2Ancestors.AppendElement(c2);
}
if (!c2 && aCommonAncestor) {
// So, it turns out aCommonAncestor was not an ancestor of c2.
// We need to retry with no common ancestor hint.
return DoCompareTreePosition(aContent1, aContent2,
aIf1Ancestor, aIf2Ancestor, nsnull);
}
int last1 = content1Ancestors.Count() - 1;
int last2 = content2Ancestors.Count() - 1;
nsIContent* content1Ancestor = nsnull;
nsIContent* content2Ancestor = nsnull;
while (last1 >= 0 && last2 >= 0
&& ((content1Ancestor = NS_STATIC_CAST(nsIContent*, content1Ancestors.ElementAt(last1)))
== (content2Ancestor = NS_STATIC_CAST(nsIContent*, content2Ancestors.ElementAt(last2))))) {
last1--;
last2--;
}
if (last1 < 0) {
if (last2 < 0) {
NS_ASSERTION(aContent1 == aContent2, "internal error?");
return 0;
} else {
// aContent1 is an ancestor of aContent2
return aIf1Ancestor;
}
} else {
if (last2 < 0) {
// aContent2 is an ancestor of aContent1
return aIf2Ancestor;
} else {
// content1Ancestor != content2Ancestor, so they must be siblings with the same parent
nsIContent* parent = content1Ancestor->GetParent();
NS_ASSERTION(parent, "no common ancestor at all???");
if (!parent) { // different documents??
return 0;
}
PRInt32 index1 = parent->IndexOf(content1Ancestor);
PRInt32 index2 = parent->IndexOf(content2Ancestor);
if (index1 < 0 || index2 < 0) {
// one of them must be anonymous; we can't determine the order
return 0;
}
return index1 - index2;
}
}
}
// static
nsIFrame* nsLayoutUtils::GetLastSibling(nsIFrame* aFrame) {
if (!aFrame) {
return nsnull;
}
nsIFrame* next;
while ((next = aFrame->GetNextSibling()) != nsnull) {
aFrame = next;
}
return aFrame;
}
// static
nsIView*
nsLayoutUtils::FindSiblingViewFor(nsIView* aParentView, nsIFrame* aFrame) {
nsIFrame* parentViewFrame = NS_STATIC_CAST(nsIFrame*, aParentView->GetClientData());
nsIContent* parentViewContent = parentViewFrame ? parentViewFrame->GetContent() : nsnull;
for (nsIView* insertBefore = aParentView->GetFirstChild(); insertBefore;
insertBefore = insertBefore->GetNextSibling()) {
nsIFrame* f = NS_STATIC_CAST(nsIFrame*, insertBefore->GetClientData());
if (!f) {
// this view could be some anonymous view attached to a meaningful parent
for (nsIView* searchView = insertBefore->GetParent(); searchView;
searchView = searchView->GetParent()) {
f = NS_STATIC_CAST(nsIFrame*, searchView->GetClientData());
if (f) {
break;
}
}
NS_ASSERTION(f, "Can't find a frame anywhere!");
}
if (!f || !aFrame->GetContent() || !f->GetContent() ||
CompareTreePosition(aFrame->GetContent(), f->GetContent(), parentViewContent) > 0) {
// aFrame's content is after f's content (or we just don't know),
// so put our view before f's view
return insertBefore;
}
}
return nsnull;
}
//static
nsIScrollableFrame*
nsLayoutUtils::GetScrollableFrameFor(nsIFrame *aScrolledFrame)
{
nsIFrame *frame = aScrolledFrame->GetParent();
if (!frame) {
return nsnull;
}
nsIScrollableFrame *sf;
CallQueryInterface(frame, &sf);
return sf;
}
//static
nsIScrollableFrame*
nsLayoutUtils::GetScrollableFrameFor(nsIScrollableView *aScrollableView)
{
nsIFrame *frame = GetFrameFor(aScrollableView->View()->GetParent());
if (frame) {
nsIScrollableFrame *sf;
CallQueryInterface(frame, &sf);
return sf;
}
return nsnull;
}
//static
nsPresContext::ScrollbarStyles
nsLayoutUtils::ScrollbarStylesOfView(nsIScrollableView *aScrollableView)
{
nsIScrollableFrame *sf = GetScrollableFrameFor(aScrollableView);
return sf ? sf->GetScrollbarStyles() :
nsPresContext::ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN,
NS_STYLE_OVERFLOW_HIDDEN);
}
// static
nsIScrollableView*
nsLayoutUtils::GetNearestScrollingView(nsIView* aView, Direction aDirection)
{
// If aDirection is eEither, find first view with a scrolllable frame.
// Otherwise, find the first view that has a scrollable frame whose
// ScrollbarStyles is not NS_STYLE_OVERFLOW_HIDDEN in aDirection
// and where there is something currently not visible
// that can be scrolled to in aDirection.
NS_ASSERTION(aView, "GetNearestScrollingView expects a non-null view");
nsIScrollableView* scrollableView = nsnull;
for (; aView; aView = aView->GetParent()) {
scrollableView = aView->ToScrollableView();
if (scrollableView) {
nsPresContext::ScrollbarStyles ss =
nsLayoutUtils::ScrollbarStylesOfView(scrollableView);
nsIScrollableFrame *scrollableFrame = GetScrollableFrameFor(scrollableView);
NS_ASSERTION(scrollableFrame, "Must have scrollable frame for view!");
nsMargin margin = scrollableFrame->GetActualScrollbarSizes();
// Get size of total scrollable area
nscoord totalWidth, totalHeight;
scrollableView->GetContainerSize(&totalWidth, &totalHeight);
// Get size of currently visible area
nsSize visibleSize = aView->GetBounds().Size();
// aDirection can be eHorizontal, eVertical, or eEither
// If scrolling in a specific direction, require visible scrollbars or
// something to scroll to in that direction.
if (aDirection != eHorizontal &&
ss.mVertical != NS_STYLE_OVERFLOW_HIDDEN &&
(aDirection == eEither || totalHeight > visibleSize.height || margin.right))
break;
if (aDirection != eVertical &&
ss.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN &&
(aDirection == eEither || totalWidth > visibleSize.width || margin.bottom))
break;
}
}
return scrollableView;
}
nsPoint
nsLayoutUtils::GetDOMEventCoordinatesRelativeTo(nsIDOMEvent* aDOMEvent, nsIFrame* aFrame)
{
nsCOMPtr<nsIPrivateDOMEvent> privateEvent(do_QueryInterface(aDOMEvent));
NS_ASSERTION(privateEvent, "bad implementation");
if (!privateEvent)
return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
nsEvent* event;
nsresult rv = privateEvent->GetInternalNSEvent(&event);
if (NS_FAILED(rv))
return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
if (!event || event->eventStructType != NS_MOUSE_EVENT)
return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
nsGUIEvent* GUIEvent = NS_STATIC_CAST(nsGUIEvent*, event);
if (!GUIEvent->widget)
return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
nsIView* view = nsIView::GetViewFor(GUIEvent->widget);
if (!view)
return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
nsPoint widgetToView;
view->GetNearestWidget(&widgetToView);
nsPoint viewToFrame;
nsIView* frameView = aFrame->GetClosestView(&viewToFrame);
float p2t = aFrame->GetPresContext()->PixelsToTwips();
nsPoint mousePt(NSIntPixelsToTwips(GUIEvent->refPoint.x, p2t),
NSIntPixelsToTwips(GUIEvent->refPoint.y, p2t));
return mousePt + widgetToView + (-frameView->GetOffsetTo(view)) + viewToFrame;
}
// Combine aNewBreakType with aOrigBreakType, but limit the break types
// to NS_STYLE_CLEAR_LEFT, RIGHT, LEFT_AND_RIGHT.
PRUint8
nsLayoutUtils::CombineBreakType(PRUint8 aOrigBreakType,
PRUint8 aNewBreakType)
{
PRUint8 breakType = aOrigBreakType;
switch(breakType) {
case NS_STYLE_CLEAR_LEFT:
if ((NS_STYLE_CLEAR_RIGHT == aNewBreakType) ||
(NS_STYLE_CLEAR_LEFT_AND_RIGHT == aNewBreakType)) {
breakType = NS_STYLE_CLEAR_LEFT_AND_RIGHT;
}
break;
case NS_STYLE_CLEAR_RIGHT:
if ((NS_STYLE_CLEAR_LEFT == aNewBreakType) ||
(NS_STYLE_CLEAR_LEFT_AND_RIGHT == aNewBreakType)) {
breakType = NS_STYLE_CLEAR_LEFT_AND_RIGHT;
}
break;
case NS_STYLE_CLEAR_NONE:
if ((NS_STYLE_CLEAR_LEFT == aNewBreakType) ||
(NS_STYLE_CLEAR_RIGHT == aNewBreakType) ||
(NS_STYLE_CLEAR_LEFT_AND_RIGHT == aNewBreakType)) {
breakType = aNewBreakType;
}
}
return breakType;
}
PRBool
nsLayoutUtils::IsInitialContainingBlock(nsIFrame* aFrame)
{
return aFrame ==
aFrame->GetPresContext()->PresShell()->FrameConstructor()->GetInitialContainingBlock();
}