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pjs/layout/generic/nsHTMLContainerFrame.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Netscape Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the NPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the NPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsHTMLContainerFrame.h"
#include "nsIRenderingContext.h"
#include "nsIPresContext.h"
#include "nsIPresShell.h"
#include "nsIStyleContext.h"
#include "nsStyleConsts.h"
#include "nsCSSRendering.h"
#include "nsIContent.h"
#include "nsLayoutAtoms.h"
#include "nsIWidget.h"
#include "nsILinkHandler.h"
#include "nsHTMLValue.h"
#include "nsGUIEvent.h"
#include "nsIDocument.h"
#include "nsIURL.h"
#include "nsIPtr.h"
#include "nsPlaceholderFrame.h"
#include "nsIHTMLContent.h"
#include "nsHTMLParts.h"
#include "nsIView.h"
#include "nsIViewManager.h"
#include "nsViewsCID.h"
#include "nsIReflowCommand.h"
#include "nsHTMLIIDs.h"
#include "nsIDOMEvent.h"
#include "nsIScrollableView.h"
#include "nsWidgetsCID.h"
#include "nsIStyleSet.h"
#include "nsCOMPtr.h"
static NS_DEFINE_CID(kCChildCID, NS_CHILD_CID);
NS_IMETHODIMP
nsHTMLContainerFrame::Paint(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
const nsRect& aDirtyRect,
nsFramePaintLayer aWhichLayer,
PRUint32 aFlags)
{
if (NS_FRAME_IS_UNFLOWABLE & mState) {
return NS_OK;
}
nsCOMPtr<nsIAtom> frameType;
GetFrameType(getter_AddRefs(frameType));
// Paint inline element backgrounds in the foreground layer, but
// others in the background (bug 36710).
if (((frameType.get() == nsLayoutAtoms::inlineFrame)?NS_FRAME_PAINT_LAYER_FOREGROUND:NS_FRAME_PAINT_LAYER_BACKGROUND) == aWhichLayer) {
const nsStyleVisibility* vis =
(const nsStyleVisibility*)((nsIStyleContext*)mStyleContext)->GetStyleData(eStyleStruct_Visibility);
if (vis->IsVisible() && mRect.width && mRect.height) {
// Paint our background and border
PRIntn skipSides = GetSkipSides();
const nsStyleBackground* color = (const nsStyleBackground*)
mStyleContext->GetStyleData(eStyleStruct_Background);
const nsStyleBorder* border = (const nsStyleBorder*)
mStyleContext->GetStyleData(eStyleStruct_Border);
const nsStyleOutline* outline = (const nsStyleOutline*)
mStyleContext->GetStyleData(eStyleStruct_Outline);
nsRect rect(0, 0, mRect.width, mRect.height);
nsCSSRendering::PaintBackground(aPresContext, aRenderingContext, this,
aDirtyRect, rect, *color, *border, 0, 0);
nsCSSRendering::PaintBorder(aPresContext, aRenderingContext, this,
aDirtyRect, rect, *border, mStyleContext, skipSides);
nsCSSRendering::PaintOutline(aPresContext, aRenderingContext, this,
aDirtyRect, rect, *border, *outline, mStyleContext, 0);
// The sole purpose of this is to trigger display
// of the selection window for Named Anchors,
// which don't have any children and normally don't
// have any size, but in Editor we use CSS to display
// an image to represent this "hidden" element.
if (!mFrames.FirstChild())
{
nsFrame::Paint(aPresContext, aRenderingContext, aDirtyRect, aWhichLayer, aFlags);
}
}
}
if (frameType.get() == nsLayoutAtoms::canvasFrame) {
// We are wrapping the root frame of a document. We
// need to check the pres shell to find out if painting is locked
// down (because we're still in the early stages of document
// and frame construction. If painting is locked down, then we
// do not paint our children.
PRBool paintingSuppressed = PR_FALSE;
nsCOMPtr<nsIPresShell> shell;
aPresContext->GetShell(getter_AddRefs(shell));
shell->IsPaintingSuppressed(&paintingSuppressed);
if (paintingSuppressed)
return NS_OK;
}
// Now paint the kids. Note that child elements have the opportunity to
// override the visibility property and display even if their parent is
// hidden
PaintChildren(aPresContext, aRenderingContext, aDirtyRect, aWhichLayer, aFlags);
return NS_OK;
}
/**
* Create a next-in-flow for aFrame. Will return the newly created
* frame in aNextInFlowResult <b>if and only if</b> a new frame is
* created; otherwise nsnull is returned in aNextInFlowResult.
*/
nsresult
nsHTMLContainerFrame::CreateNextInFlow(nsIPresContext* aPresContext,
nsIFrame* aOuterFrame,
nsIFrame* aFrame,
nsIFrame*& aNextInFlowResult)
{
aNextInFlowResult = nsnull;
nsIFrame* nextInFlow;
aFrame->GetNextInFlow(&nextInFlow);
if (nsnull == nextInFlow) {
// Create a continuation frame for the child frame and insert it
// into our lines child list.
nsIFrame* nextFrame;
aFrame->GetNextSibling(&nextFrame);
nsIPresShell* presShell;
nsIStyleSet* styleSet;
aPresContext->GetShell(&presShell);
presShell->GetStyleSet(&styleSet);
NS_RELEASE(presShell);
styleSet->CreateContinuingFrame(aPresContext, aFrame, aOuterFrame, &nextInFlow);
NS_RELEASE(styleSet);
if (nsnull == nextInFlow) {
return NS_ERROR_OUT_OF_MEMORY;
}
aFrame->SetNextSibling(nextInFlow);
nextInFlow->SetNextSibling(nextFrame);
NS_FRAME_LOG(NS_FRAME_TRACE_NEW_FRAMES,
("nsHTMLContainerFrame::MaybeCreateNextInFlow: frame=%p nextInFlow=%p",
aFrame, nextInFlow));
aNextInFlowResult = nextInFlow;
}
return NS_OK;
}
static nsresult
ReparentFrameViewTo(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsIViewManager* aViewManager,
nsIView* aNewParentView,
nsIView* aOldParentView)
{
nsIView* view;
// Does aFrame have a view?
aFrame->GetView(aPresContext, &view);
if (view) {
// Verify that the current parent view is what we think it is
//nsIView* parentView;
//NS_ASSERTION(parentView == aOldParentView, "unexpected parent view");
// Change the parent view.
PRInt32 zIndex;
view->GetZIndex(zIndex);
// Remove the view using it's parent instead
// of aOldParentView which is wrong.
nsIView* vp = nsnull;
view->GetParent(vp);
aViewManager->RemoveChild(vp, view);
// XXX We need to insert this view in the correct place within its z-order...
// XXX What should we do about the Z-placeholder-child if this frame is position:fixed?
aViewManager->InsertChild(aNewParentView, view, zIndex);
} else {
// Iterate the child frames, and check each child frame to see if it has
// a view
nsIFrame* childFrame;
aFrame->FirstChild(aPresContext, nsnull, &childFrame);
while (childFrame) {
ReparentFrameViewTo(aPresContext, childFrame, aViewManager, aNewParentView, aOldParentView);
childFrame->GetNextSibling(&childFrame);
}
// Also check the overflow-list
aFrame->FirstChild(aPresContext, nsLayoutAtoms::overflowList, &childFrame);
while (childFrame) {
ReparentFrameViewTo(aPresContext, childFrame, aViewManager, aNewParentView, aOldParentView);
childFrame->GetNextSibling(&childFrame);
}
// Also check the floater-list
aFrame->FirstChild(aPresContext, nsLayoutAtoms::floaterList, &childFrame);
while (childFrame) {
ReparentFrameViewTo(aPresContext, childFrame, aViewManager, aNewParentView, aOldParentView);
childFrame->GetNextSibling(&childFrame);
}
}
return NS_OK;
}
// Helper function that returns the nearest view to this frame. Checks
// this frame, its parent frame, its parent frame, ...
static nsIView*
GetClosestViewFor(nsIPresContext* aPresContext, nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null frame pointer");
nsIView* view;
do {
aFrame->GetView(aPresContext, &view);
if (view) {
break;
}
aFrame->GetParent(&aFrame);
} while (aFrame);
NS_POSTCONDITION(view, "no containing view");
return view;
}
nsresult
nsHTMLContainerFrame::ReparentFrameView(nsIPresContext* aPresContext,
nsIFrame* aChildFrame,
nsIFrame* aOldParentFrame,
nsIFrame* aNewParentFrame)
{
NS_PRECONDITION(aChildFrame, "null child frame pointer");
NS_PRECONDITION(aOldParentFrame, "null old parent frame pointer");
NS_PRECONDITION(aNewParentFrame, "null new parent frame pointer");
NS_PRECONDITION(aOldParentFrame != aNewParentFrame, "same old and new parent frame");
nsIView* childView;
nsIView* oldParentView;
nsIView* newParentView;
// This code is called often and we need it to be as fast as possible, so
// see if we can trivially detect that no work needs to be done
aChildFrame->GetView(aPresContext, &childView);
if (!childView) {
// Child frame doesn't have a view. See if it has any child frames
nsIFrame* firstChild;
aChildFrame->FirstChild(aPresContext, nsnull, &firstChild);
if (!firstChild) {
return NS_OK;
}
}
// See if either the old parent frame or the new parent frame have a view
aOldParentFrame->GetView(aPresContext, &oldParentView);
aNewParentFrame->GetView(aPresContext, &newParentView);
if (!oldParentView && !newParentView) {
// Walk up both the old parent frame and the new parent frame nodes
// stopping when we either find a common parent or views for one
// or both of the frames.
//
// This works well in the common case where we push/pull and the old parent
// frame and the new parent frame are part of the same flow. They will
// typically be the same distance (height wise) from the
do {
aOldParentFrame->GetParent(&aOldParentFrame);
aNewParentFrame->GetParent(&aNewParentFrame);
// We should never walk all the way to the root frame without finding
// a view
NS_ASSERTION(aOldParentFrame && aNewParentFrame, "didn't find view");
// See if we reached a common parent
if (aOldParentFrame == aNewParentFrame) {
break;
}
// Get the views
aOldParentFrame->GetView(aPresContext, &oldParentView);
aNewParentFrame->GetView(aPresContext, &newParentView);
} while (!(oldParentView || newParentView));
}
// See if we found a common parent frame
if (aOldParentFrame == aNewParentFrame) {
// We found a common parent and there are no views between the old parent
// and the common parent or the new parent frame and the common parent.
// Because neither the old parent frame nor the new parent frame have views,
// then any child views don't need reparenting
return NS_OK;
}
// We found views for one or both of the parent frames before we found a
// common parent
NS_ASSERTION(oldParentView || newParentView, "internal error");
if (!oldParentView) {
oldParentView = GetClosestViewFor(aPresContext, aOldParentFrame);
}
if (!newParentView) {
newParentView = GetClosestViewFor(aPresContext, aNewParentFrame);
}
// See if the old parent frame and the new parent frame are in the
// same view sub-hierarchy. If they are then we don't have to do
// anything
if (oldParentView != newParentView) {
nsCOMPtr<nsIViewManager> viewManager;
oldParentView->GetViewManager(*getter_AddRefs(viewManager));
// They're not so we need to reparent any child views
return ReparentFrameViewTo(aPresContext, aChildFrame, viewManager, newParentView,
oldParentView);
}
return NS_OK;
}
nsresult
nsHTMLContainerFrame::ReparentFrameViewList(nsIPresContext* aPresContext,
nsIFrame* aChildFrameList,
nsIFrame* aOldParentFrame,
nsIFrame* aNewParentFrame)
{
NS_PRECONDITION(aChildFrameList, "null child frame list");
NS_PRECONDITION(aOldParentFrame, "null old parent frame pointer");
NS_PRECONDITION(aNewParentFrame, "null new parent frame pointer");
NS_PRECONDITION(aOldParentFrame != aNewParentFrame, "same old and new parent frame");
nsIView* oldParentView;
nsIView* newParentView;
// See if either the old parent frame or the new parent frame have a view
aOldParentFrame->GetView(aPresContext, &oldParentView);
aNewParentFrame->GetView(aPresContext, &newParentView);
if (!oldParentView && !newParentView) {
// Walk up both the old parent frame and the new parent frame nodes
// stopping when we either find a common parent or views for one
// or both of the frames.
//
// This works well in the common case where we push/pull and the old parent
// frame and the new parent frame are part of the same flow. They will
// typically be the same distance (height wise) from the
do {
aOldParentFrame->GetParent(&aOldParentFrame);
aNewParentFrame->GetParent(&aNewParentFrame);
// We should never walk all the way to the root frame without finding
// a view
NS_ASSERTION(aOldParentFrame && aNewParentFrame, "didn't find view");
// See if we reached a common parent
if (aOldParentFrame == aNewParentFrame) {
break;
}
// Get the views
aOldParentFrame->GetView(aPresContext, &oldParentView);
aNewParentFrame->GetView(aPresContext, &newParentView);
} while (!(oldParentView || newParentView));
}
// See if we found a common parent frame
if (aOldParentFrame == aNewParentFrame) {
// We found a common parent and there are no views between the old parent
// and the common parent or the new parent frame and the common parent.
// Because neither the old parent frame nor the new parent frame have views,
// then any child views don't need reparenting
return NS_OK;
}
// We found views for one or both of the parent frames before we found a
// common parent
NS_ASSERTION(oldParentView || newParentView, "internal error");
if (!oldParentView) {
oldParentView = GetClosestViewFor(aPresContext, aOldParentFrame);
}
if (!newParentView) {
newParentView = GetClosestViewFor(aPresContext, aNewParentFrame);
}
// See if the old parent frame and the new parent frame are in the
// same view sub-hierarchy. If they are then we don't have to do
// anything
if (oldParentView != newParentView) {
nsCOMPtr<nsIViewManager> viewManager;
oldParentView->GetViewManager(*getter_AddRefs(viewManager));
// They're not so we need to reparent any child views
for (nsIFrame* f = aChildFrameList; f; f->GetNextSibling(&f)) {
ReparentFrameViewTo(aPresContext, f, viewManager, newParentView,
oldParentView);
}
}
return NS_OK;
}
static PRBool
IsContainerContent(nsIFrame* aFrame)
{
nsIContent* content;
PRBool result = PR_FALSE;
aFrame->GetContent(&content);
if (content) {
content->CanContainChildren(result);
NS_RELEASE(content);
}
return result;
}
nsresult
nsHTMLContainerFrame::CreateViewForFrame(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsIStyleContext* aStyleContext,
nsIFrame* aContentParentFrame,
PRBool aForce)
{
nsIView* view;
aFrame->GetView(aPresContext, &view);
// If we don't yet have a view, see if we need a view
if (nsnull == view) {
PRBool fixedBackgroundAttachment = PR_FALSE;
// Get nsStyleColor and nsStyleDisplay
const nsStyleBackground* color = (const nsStyleBackground*)
aStyleContext->GetStyleData(eStyleStruct_Background);
const nsStyleDisplay* display = (const nsStyleDisplay*)
aStyleContext->GetStyleData(eStyleStruct_Display);
const nsStylePosition* position = (const nsStylePosition*)
aStyleContext->GetStyleData(eStyleStruct_Position);
const nsStyleVisibility* vis = (const nsStyleVisibility*)
aStyleContext->GetStyleData(eStyleStruct_Visibility);
if (vis->mOpacity != 1.0f) {
NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
("nsHTMLContainerFrame::CreateViewForFrame: frame=%p opacity=%g",
aFrame, vis->mOpacity));
aForce = PR_TRUE;
}
// See if the frame has a fixed background attachment
if (NS_STYLE_BG_ATTACHMENT_FIXED == color->mBackgroundAttachment) {
aForce = PR_TRUE;
fixedBackgroundAttachment = PR_TRUE;
}
// See if the frame is being relatively positioned or absolutely
// positioned
if (!aForce) {
if (NS_STYLE_POSITION_RELATIVE == display->mPosition) {
NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
("nsHTMLContainerFrame::CreateViewForFrame: frame=%p relatively positioned",
aFrame));
aForce = PR_TRUE;
} else if (display->IsAbsolutelyPositioned()) {
NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
("nsHTMLContainerFrame::CreateViewForFrame: frame=%p absolutely positioned",
aFrame));
aForce = PR_TRUE;
}
}
// See if the frame is a scrolled frame
if (!aForce) {
nsIAtom* pseudoTag;
aStyleContext->GetPseudoType(pseudoTag);
if (pseudoTag == nsLayoutAtoms::scrolledContentPseudo) {
NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
("nsHTMLContainerFrame::CreateViewForFrame: scrolled frame=%p", aFrame));
aForce = PR_TRUE;
}
NS_IF_RELEASE(pseudoTag);
}
// See if the frame is block-level and has 'overflow' set to 'hidden'. If
// so and it can have child frames, then we need to give it a view so clipping
// of any child views works correctly. Note that if it's floated it is also
// block-level, but we can't trust that the style context 'display' value is
// set correctly
if (!aForce) {
if ((display->IsBlockLevel() || display->IsFloating()) &&
(display->mOverflow == NS_STYLE_OVERFLOW_HIDDEN)) {
// The reason for the check of whether it can contain children is just
// to avoid giving it a view unnecessarily
if (::IsContainerContent(aFrame)) {
// XXX Check for the frame being a block frame and only force a view
// in that case, because adding a view for box frames seems to cause
// problems for XUL...
nsIAtom* frameType;
aFrame->GetFrameType(&frameType);
if ((frameType == nsLayoutAtoms::blockFrame) ||
(frameType == nsLayoutAtoms::areaFrame)) {
aForce = PR_TRUE;
}
NS_IF_RELEASE(frameType);
}
}
}
if (aForce) {
// Create a view
nsIFrame* parent = nsnull;
nsIView* parentView = nsnull;
aFrame->GetParentWithView(aPresContext, &parent);
NS_ASSERTION(parent, "GetParentWithView failed");
parent->GetView(aPresContext, &parentView);
NS_ASSERTION(parentView, "no parent with view");
// Create a view
static NS_DEFINE_CID(kViewCID, NS_VIEW_CID);
nsresult result = nsComponentManager::CreateInstance(kViewCID,
nsnull,
NS_GET_IID(nsIView),
(void **)&view);
if (NS_OK == result) {
nsIViewManager* viewManager;
parentView->GetViewManager(viewManager);
NS_ASSERTION(nsnull != viewManager, "null view manager");
// Initialize the view
nsRect bounds;
aFrame->GetRect(bounds);
view->Init(viewManager, bounds, parentView);
// If the frame has a fixed background attachment, then indicate that the
// view's contents should be repainted and not bitblt'd
if (fixedBackgroundAttachment) {
PRUint32 viewFlags;
view->GetViewFlags(&viewFlags);
view->SetViewFlags(viewFlags | NS_VIEW_PUBLIC_FLAG_DONT_BITBLT);
}
// Insert the view into the view hierarchy. If the parent view is a
// scrolling view we need to do this differently
nsIScrollableView* scrollingView;
if (NS_SUCCEEDED(parentView->QueryInterface(NS_GET_IID(nsIScrollableView), (void**)&scrollingView))) {
scrollingView->SetScrolledView(view);
} else {
PRInt32 zIndex = 0;
PRBool autoZIndex = PR_FALSE;
// Get the z-index to use
if (position->mZIndex.GetUnit() == eStyleUnit_Integer) {
zIndex = position->mZIndex.GetIntValue();
} else if (position->mZIndex.GetUnit() == eStyleUnit_Auto) {
autoZIndex = PR_TRUE;
}
viewManager->InsertChild(parentView, view, zIndex);
if (autoZIndex) {
viewManager->SetViewAutoZIndex(view, PR_TRUE);
}
if (nsnull != aContentParentFrame) {
// If, for some reason, GetView below fails to initialize zParentView,
// then ensure that we completely bypass InsertZPlaceholder below.
// The effect will be as if we never knew about aContentParentFrame
// in the first place, so at least this code won't be doing any damage.
nsIView* zParentView = parentView;
aContentParentFrame->GetView(aPresContext, &zParentView);
if (nsnull == zParentView) {
nsIFrame* zParentFrame = nsnull;
aContentParentFrame->GetParentWithView(aPresContext, &zParentFrame);
NS_ASSERTION(zParentFrame, "GetParentWithView failed");
zParentFrame->GetView(aPresContext, &zParentView);
NS_ASSERTION(zParentView, "no parent with view");
}
if (zParentView != parentView) {
viewManager->InsertZPlaceholder(zParentView, view, zIndex);
}
}
}
// See if the view should be hidden
PRBool viewIsVisible = PR_TRUE;
PRBool viewHasTransparentContent = (color->mBackgroundFlags &
NS_STYLE_BG_COLOR_TRANSPARENT) == NS_STYLE_BG_COLOR_TRANSPARENT;
if (NS_STYLE_VISIBILITY_COLLAPSE == vis->mVisible) {
viewIsVisible = PR_FALSE;
}
else if (NS_STYLE_VISIBILITY_HIDDEN == vis->mVisible) {
// If it has a widget, hide the view because the widget can't deal with it
nsIWidget* widget = nsnull;
view->GetWidget(widget);
if (widget) {
viewIsVisible = PR_FALSE;
NS_RELEASE(widget);
}
else {
// If it's a container element, then leave the view visible, but
// mark it as having transparent content. The reason we need to
// do this is that child elements can override their parent's
// hidden visibility and be visible anyway.
//
// Because this function is called before processing the content
// object's child elements, we can't tell if it's a leaf by looking
// at whether the frame has any child frames
if (::IsContainerContent(aFrame)) {
// The view needs to be visible, but marked as having transparent
// content
viewHasTransparentContent = PR_TRUE;
} else {
// Go ahead and hide the view
viewIsVisible = PR_FALSE;
}
}
}
if (viewIsVisible) {
if (viewHasTransparentContent) {
viewManager->SetViewContentTransparency(view, PR_TRUE);
}
} else {
view->SetVisibility(nsViewVisibility_kHide);
}
// XXX If it's fixed positioned, then create a widget so it floats
// above the scrolling area
if (NS_STYLE_POSITION_FIXED == display->mPosition) {
view->CreateWidget(kCChildCID);
}
viewManager->SetViewOpacity(view, vis->mOpacity);
NS_RELEASE(viewManager);
}
// Remember our view
aFrame->SetView(aPresContext, view);
NS_FRAME_LOG(NS_FRAME_TRACE_CALLS,
("nsHTMLContainerFrame::CreateViewForFrame: frame=%p view=%p",
aFrame));
return result;
}
}
return NS_OK;
}
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