gecko-dev/layout/generic/nsViewportFrame.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#include "nsCOMPtr.h"
#include "nsContainerFrame.h"
#include "nsHTMLParts.h"
#include "nsHTMLIIDs.h"
#include "nsLayoutAtoms.h"
#include "nsIViewManager.h"
#include "nsIScrollableView.h"
#include "nsIDeviceContext.h"
#include "nsIPresContext.h"
static NS_DEFINE_IID(kIFrameIID, NS_IFRAME_IID);
static NS_DEFINE_IID(kScrollViewIID, NS_ISCROLLABLEVIEW_IID);
/**
* Viewport frame class.
*
* The viewport frame is the parent frame for the document element's frame.
* It only supports having a single child frame which must be one of the
* following:
* - scroll frame
* - root frame
*
* The viewport frame has an additional named child list:
* - "Fixed-list" which contains the fixed positioned frames
*
* @see nsLayoutAtoms::fixedList
*/
class ViewportFrame : public nsContainerFrame {
public:
NS_IMETHOD DeleteFrame(nsIPresContext& aPresContext);
NS_IMETHOD SetInitialChildList(nsIPresContext& aPresContext,
nsIAtom* aListName,
nsIFrame* aChildList);
NS_IMETHOD GetAdditionalChildListName(PRInt32 aIndex,
nsIAtom** aListName) const;
NS_IMETHOD FirstChild(nsIAtom* aListName, nsIFrame** aFirstChild) const;
NS_IMETHOD Reflow(nsIPresContext& aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus);
/**
* Get the "type" of the frame
*
* @see nsLayoutAtoms::viewportFrame
*/
NS_IMETHOD GetFrameType(nsIAtom** aType) const;
NS_IMETHOD GetFrameName(nsString& aResult) const;
protected:
nsresult IncrementalReflow(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState);
nsresult ReflowFixedFrame(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState,
nsIFrame* aKidFrame,
PRBool aInitialReflow,
nsReflowStatus& aStatus) const;
void ReflowFixedFrames(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState) const;
void CalculateFixedContainingBlockSize(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState,
nscoord& aWidth,
nscoord& aHeight) const;
private:
nsFrameList mFixedFrames; // additional named child list
};
//----------------------------------------------------------------------
nsresult
NS_NewViewportFrame(nsIFrame*& aResult)
{
ViewportFrame* frame = new ViewportFrame;
if (nsnull == frame) {
return NS_ERROR_OUT_OF_MEMORY;
}
aResult = frame;
return NS_OK;
}
NS_IMETHODIMP
ViewportFrame::DeleteFrame(nsIPresContext& aPresContext)
{
mFixedFrames.DeleteFrames(aPresContext);
return nsContainerFrame::DeleteFrame(aPresContext);
}
NS_IMETHODIMP
ViewportFrame::SetInitialChildList(nsIPresContext& aPresContext,
nsIAtom* aListName,
nsIFrame* aChildList)
{
nsresult rv;
if (nsLayoutAtoms::fixedList == aListName) {
mFixedFrames.SetFrames(aChildList);
rv = NS_OK;
} else {
rv = nsContainerFrame::SetInitialChildList(aPresContext, aListName, aChildList);
}
return rv;
}
NS_IMETHODIMP
ViewportFrame::GetAdditionalChildListName(PRInt32 aIndex,
nsIAtom** aListName) const
{
NS_PRECONDITION(nsnull != aListName, "null OUT parameter pointer");
*aListName = nsnull;
if (aIndex < 0) {
return NS_ERROR_INVALID_ARG;
} else if (0 == aIndex) {
*aListName = nsLayoutAtoms::fixedList;
NS_ADDREF(*aListName);
}
return NS_OK;
}
NS_IMETHODIMP
ViewportFrame::FirstChild(nsIAtom* aListName, nsIFrame** aFirstChild) const
{
NS_PRECONDITION(nsnull != aFirstChild, "null OUT parameter pointer");
if (aListName == nsLayoutAtoms::fixedList) {
*aFirstChild = mFixedFrames.FirstChild();
return NS_OK;
}
return nsContainerFrame::FirstChild(aListName, aFirstChild);
}
void
ViewportFrame::CalculateFixedContainingBlockSize(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState,
nscoord& aWidth,
nscoord& aHeight) const
{
// Initialize the values to the computed width/height in our reflow
// state struct
aWidth = aReflowState.computedWidth;
aHeight = aReflowState.computedHeight;
// Get our prinicpal child frame and see if we're scrollable
nsIFrame* kidFrame = mFrames.FirstChild();
nsIView* kidView;
kidFrame->GetView(&kidView);
if (nsnull != kidView) {
nsIScrollableView* scrollingView;
if (NS_SUCCEEDED(kidView->QueryInterface(kScrollViewIID, (void**)&scrollingView))) {
// Get the scrollbar dimensions
float sbWidth, sbHeight;
nsCOMPtr<nsIDeviceContext> dc;
aPresContext.GetDeviceContext(getter_AddRefs(dc));
dc->GetScrollBarDimensions(sbWidth, sbHeight);
// See if the scrollbars are visible
PRBool vertSBVisible, horzSBVisible;
scrollingView->GetScrollbarVisibility(&vertSBVisible, &horzSBVisible);
if (vertSBVisible) {
aWidth -= NSToCoordRound(sbWidth);
}
if (horzSBVisible) {
aHeight -= NSToCoordRound(sbHeight);
}
}
}
}
nsresult
ViewportFrame::ReflowFixedFrame(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState,
nsIFrame* aKidFrame,
PRBool aInitialReflow,
nsReflowStatus& aStatus) const
{
// Reflow the frame
nsIHTMLReflow* htmlReflow;
nsresult rv;
rv = aKidFrame->QueryInterface(kIHTMLReflowIID, (void**)&htmlReflow);
if (NS_SUCCEEDED(rv)) {
htmlReflow->WillReflow(aPresContext);
nsHTMLReflowMetrics kidDesiredSize(nsnull);
nsSize availSize(aReflowState.availableWidth, NS_UNCONSTRAINEDSIZE);
nsHTMLReflowState kidReflowState(aPresContext, aReflowState, aKidFrame,
availSize);
// If it's the initial reflow, then override the reflow reason. This is
// used when frames are inserted incrementally
if (aInitialReflow) {
kidReflowState.reason = eReflowReason_Initial;
}
htmlReflow->Reflow(aPresContext, kidDesiredSize, kidReflowState, aStatus);
// XXX If the child had a fixed height, then make sure it respected it...
if (NS_AUTOHEIGHT != kidReflowState.computedHeight) {
if (kidDesiredSize.height < kidReflowState.computedHeight) {
kidDesiredSize.height = kidReflowState.computedHeight;
kidDesiredSize.height += kidReflowState.mComputedBorderPadding.top +
kidReflowState.mComputedBorderPadding.bottom;
}
}
// Position the child
nsRect rect(kidReflowState.computedOffsets.left + kidReflowState.computedMargin.left,
kidReflowState.computedOffsets.top + kidReflowState.computedMargin.top,
kidDesiredSize.width, kidDesiredSize.height);
aKidFrame->SetRect(rect);
htmlReflow->DidReflow(aPresContext, NS_FRAME_REFLOW_FINISHED);
}
return rv;
}
// Called by Reflow() to reflow all of the fixed positioned child frames.
// This is only done for 'initial', 'resize', and 'style change' reflow commands
void
ViewportFrame::ReflowFixedFrames(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState) const
{
NS_PRECONDITION(eReflowReason_Incremental != aReflowState.reason,
"unexpected reflow reason");
// Calculate how much room is available for the fixed items. That means
// determining if the viewport is scrollable and whether the vertical and/or
// horizontal scrollbars are visible
nscoord width, height;
CalculateFixedContainingBlockSize(aPresContext, aReflowState, width, height);
// Make a copy of the reflow state and change the computed width and height
// to reflect the available space for the fixed items
// XXX Find a cleaner way to do this...
nsHTMLReflowState reflowState(aReflowState);
reflowState.computedWidth = width;
reflowState.computedHeight = height;
nsIFrame* kidFrame;
for (kidFrame = mFixedFrames.FirstChild(); nsnull != kidFrame; kidFrame->GetNextSibling(&kidFrame)) {
// Reflow the frame using our reflow reason
nsReflowStatus kidStatus;
ReflowFixedFrame(aPresContext, reflowState, kidFrame, PR_FALSE, kidStatus);
}
}
/**
* Called by Reflow() to handle the case where it's an incremental reflow
* of a fixed child frame
*/
nsresult
ViewportFrame::IncrementalReflow(nsIPresContext& aPresContext,
const nsHTMLReflowState& aReflowState)
{
nsIReflowCommand::ReflowType type;
nsIFrame* newFrames;
PRInt32 numFrames;
// Get the type of reflow command
aReflowState.reflowCommand->GetType(type);
// Handle each specific type
if (nsIReflowCommand::FrameAppended == type) {
// Add the frames to our list of fixed position frames
aReflowState.reflowCommand->GetChildFrame(newFrames);
NS_ASSERTION(nsnull != newFrames, "null child list");
numFrames = LengthOf(newFrames);
mFixedFrames.AppendFrames(nsnull, newFrames);
} else if (nsIReflowCommand::FrameRemoved == type) {
// Get the new frame
nsIFrame* childFrame;
aReflowState.reflowCommand->GetChildFrame(childFrame);
PRBool result = mFixedFrames.DeleteFrame(aPresContext, childFrame);
NS_ASSERTION(result, "didn't find frame to delete");
} else if (nsIReflowCommand::FrameInserted == type) {
// Get the previous sibling
nsIFrame* prevSibling;
aReflowState.reflowCommand->GetPrevSiblingFrame(prevSibling);
// Insert the new frames
aReflowState.reflowCommand->GetChildFrame(newFrames);
NS_ASSERTION(nsnull != newFrames, "null child list");
numFrames = LengthOf(newFrames);
mFixedFrames.InsertFrames(nsnull, prevSibling, newFrames);
} else {
NS_ASSERTION(PR_FALSE, "unexpected reflow type");
}
// For inserted and appended reflow commands we need to reflow the
// newly added frames
if ((nsIReflowCommand::FrameAppended == type) ||
(nsIReflowCommand::FrameInserted == type)) {
while (numFrames-- > 0) {
// Calculate how much room is available for the fixed items. That means
// determining if the viewport is scrollable and whether the vertical and/or
// horizontal scrollbars are visible
nscoord width, height;
CalculateFixedContainingBlockSize(aPresContext, aReflowState, width, height);
// Make a copy of the reflow state and change the computed width and height
// to reflect the available space for the fixed items
// XXX Find a cleaner way to do this...
nsHTMLReflowState reflowState(aReflowState);
reflowState.computedWidth = width;
reflowState.computedHeight = height;
nsReflowStatus status;
ReflowFixedFrame(aPresContext, reflowState, newFrames, PR_TRUE, status);
newFrames->GetNextSibling(&newFrames);
}
}
return NS_OK;
}
NS_IMETHODIMP
ViewportFrame::Reflow(nsIPresContext& aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
NS_FRAME_TRACE_REFLOW_IN("ViewportFrame::Reflow");
NS_PRECONDITION(nsnull == aDesiredSize.maxElementSize, "unexpected request");
// Initialize OUT parameter
aStatus = NS_FRAME_COMPLETE;
nsIFrame* nextFrame = nsnull;
PRBool isHandled = PR_FALSE;
// Check for an incremental reflow
if (eReflowReason_Incremental == aReflowState.reason) {
// See if we're the target frame
nsIFrame* targetFrame;
aReflowState.reflowCommand->GetTarget(targetFrame);
if (this == targetFrame) {
nsIAtom* listName;
PRBool isFixedChild;
// It's targeted at us. It better be for a 'fixed' frame
// reflow command
aReflowState.reflowCommand->GetChildListName(listName);
isFixedChild = nsLayoutAtoms::fixedList == listName;
NS_IF_RELEASE(listName);
NS_ASSERTION(isFixedChild, "unexpected child list");
if (isFixedChild) {
IncrementalReflow(aPresContext, aReflowState);
isHandled = PR_TRUE;
}
} else {
// Get the next frame in the reflow chain
aReflowState.reflowCommand->GetNext(nextFrame);
}
}
if (!isHandled) {
if ((eReflowReason_Incremental == aReflowState.reason) &&
(mFixedFrames.ContainsFrame(nextFrame))) {
// Reflow the 'fixed' frame that's the next frame in the reflow path
nsReflowStatus kidStatus;
ReflowFixedFrame(aPresContext, aReflowState, nextFrame, PR_FALSE,
kidStatus);
// XXX Make sure the frame is repainted. For the time being, since we
// have no idea what actually changed repaint it all...
nsIView* view;
nextFrame->GetView(&view);
if (nsnull != view) {
nsIViewManager* viewMgr;
view->GetViewManager(viewMgr);
if (nsnull != viewMgr) {
viewMgr->UpdateView(view, (nsIRegion*)nsnull, NS_VMREFRESH_NO_SYNC);
NS_RELEASE(viewMgr);
}
}
} else {
// Reflow our one and only principal child frame
if (mFrames.NotEmpty()) {
nsIFrame* kidFrame = mFrames.FirstChild();
nsHTMLReflowMetrics kidDesiredSize(nsnull);
nsSize availableSpace(aReflowState.availableWidth,
aReflowState.availableHeight);
nsHTMLReflowState kidReflowState(aPresContext, aReflowState,
kidFrame, availableSpace);
// Reflow the frame
nsIHTMLReflow* htmlReflow;
if (NS_OK == kidFrame->QueryInterface(kIHTMLReflowIID, (void**)&htmlReflow)) {
kidReflowState.computedHeight = aReflowState.availableHeight;
ReflowChild(kidFrame, aPresContext, kidDesiredSize, kidReflowState,
aStatus);
nsRect rect(0, 0, kidDesiredSize.width, kidDesiredSize.height);
kidFrame->SetRect(rect);
// XXX We should resolve the details of who/when DidReflow()
// notifications are sent...
htmlReflow->DidReflow(aPresContext, NS_FRAME_REFLOW_FINISHED);
}
}
// If it's a 'initial', 'resize', or 'style change' reflow command (anything
// but incremental), then reflow all the fixed positioned child frames
if (eReflowReason_Incremental != aReflowState.reason) {
ReflowFixedFrames(aPresContext, aReflowState);
}
}
}
// Return the max size as our desired size
aDesiredSize.width = aReflowState.availableWidth;
aDesiredSize.height = aReflowState.availableHeight;
aDesiredSize.ascent = aReflowState.availableHeight;
aDesiredSize.descent = 0;
NS_FRAME_TRACE_REFLOW_OUT("ViewportFrame::Reflow", aStatus);
return NS_OK;
}
NS_IMETHODIMP
ViewportFrame::GetFrameType(nsIAtom** aType) const
{
NS_PRECONDITION(nsnull != aType, "null OUT parameter pointer");
*aType = nsLayoutAtoms::viewportFrame;
NS_ADDREF(*aType);
return NS_OK;
}
NS_IMETHODIMP
ViewportFrame::GetFrameName(nsString& aResult) const
{
return MakeFrameName("Viewport", aResult);
}