pjs/layout/base/nsPresContext.cpp

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C++

/* -*- 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 "nsPresContext.h"
#include "nsIPresShell.h"
#include "nsIContent.h"
#include "nsILinkHandler.h"
#include "nsIStyleContext.h"
#include "nsIStyleSet.h"
#include "nsIFontMetrics.h"
#include "nsFrameImageLoader.h"
#include "nsIImageManager.h"
#include "nsIImageGroup.h"
#include "nsIFrame.h"
#include "nsIRenderingContext.h"
#include "nsTransform2D.h"
#include "nsIDocument.h"
#include "nsIURL.h"
#include "nsString.h"
#define NOISY_IMAGES
static NS_DEFINE_IID(kIPresContextIID, NS_IPRESCONTEXT_IID);
nsPresContext::nsPresContext()
: mVisibleArea(0, 0, 0, 0),
mDefaultFont("Times", NS_FONT_STYLE_NORMAL,
NS_FONT_VARIANT_NORMAL,
NS_FONT_WEIGHT_NORMAL,
0,
NS_POINTS_TO_TWIPS_INT(12))
{
NS_INIT_REFCNT();
mShell = nsnull;
mDeviceContext = nsnull;
mImageGroup = nsnull;
mLinkHandler = nsnull;
mContainer = nsnull;
}
nsPresContext::~nsPresContext()
{
mShell = nsnull;
// XXX there is a race between an async notify and this code because
// the presentation shell code deletes the frame tree first and then
// deletes us. We need an "Deactivation" hook for this code too
// Release all the image loaders
PRInt32 n = mImageLoaders.Count();
for (PRInt32 i = 0; i < n; i++) {
nsIFrameImageLoader* loader;
loader = (nsIFrameImageLoader*) mImageLoaders.ElementAt(i);
NS_RELEASE(loader);
}
// XXX Tell the image library we are done with the cached images?
if (nsnull != mImageGroup) {
/*XXX mImageGroup->Interrupt(); required? */
NS_RELEASE(mImageGroup);
}
NS_IF_RELEASE(mLinkHandler);
NS_IF_RELEASE(mContainer);
}
nsrefcnt
nsPresContext::AddRef(void)
{
return ++mRefCnt;
}
nsrefcnt
nsPresContext::Release(void)
{
NS_PRECONDITION(0 != mRefCnt, "bad refcnt");
if (--mRefCnt == 0) {
delete this;
return 0;
}
return mRefCnt;
}
NS_IMPL_QUERY_INTERFACE(nsPresContext, kIPresContextIID);
// Note: We don't hold a reference on the shell; it has a reference to
// us
void
nsPresContext::SetShell(nsIPresShell* aShell)
{
mShell = aShell;
}
nsIPresShell*
nsPresContext::GetShell()
{
NS_IF_ADDREF(mShell);
return mShell;
}
nsIStyleContext*
nsPresContext::ResolveStyleContextFor(nsIContent* aContent,
nsIFrame* aParentFrame)
{
nsIStyleContext* result = nsnull;
nsIStyleSet* set = mShell->GetStyleSet();
if (nsnull != set) {
result = set->ResolveStyleFor(this, aContent, aParentFrame);
NS_RELEASE(set);
}
return result;
}
nsIStyleContext*
nsPresContext::ResolvePseudoStyleContextFor(nsIAtom* aPseudoTag,
nsIFrame* aParentFrame)
{
nsIStyleContext* result = nsnull;
nsIStyleSet* set = mShell->GetStyleSet();
if (nsnull != set) {
result = set->ResolvePseudoStyleFor(this, aPseudoTag, aParentFrame);
NS_RELEASE(set);
}
return result;
}
nsIStyleContext*
nsPresContext::ProbePseudoStyleContextFor(nsIAtom* aPseudoTag,
nsIFrame* aParentFrame)
{
nsIStyleContext* result = nsnull;
nsIStyleSet* set = mShell->GetStyleSet();
if (nsnull != set) {
result = set->ProbePseudoStyleFor(this, aPseudoTag, aParentFrame);
NS_RELEASE(set);
}
return result;
}
nsIFontMetrics*
nsPresContext::GetMetricsFor(const nsFont& aFont)
{
if (nsnull != mDeviceContext)
return mDeviceContext->GetMetricsFor(aFont);
return nsnull;
}
const nsFont&
nsPresContext::GetDefaultFont(void)
{
return mDefaultFont;
}
nsRect
nsPresContext::GetVisibleArea()
{
return mVisibleArea;
}
void
nsPresContext::SetVisibleArea(const nsRect& r)
{
mVisibleArea = r;
}
float
nsPresContext::GetPixelsToTwips() const
{
if (nsnull != mDeviceContext) {
return mDeviceContext->GetDevUnitsToAppUnits();
}
return 1.0f;
}
float
nsPresContext::GetTwipsToPixels() const
{
if (nsnull != mDeviceContext) {
return mDeviceContext->GetAppUnitsToDevUnits();
}
return 1.0f;
}
nsIDeviceContext*
nsPresContext::GetDeviceContext() const
{
NS_IF_ADDREF(mDeviceContext);
return mDeviceContext;
}
NS_METHOD
nsPresContext::GetImageGroup(nsIImageGroup*& aGroupResult)
{
if (nsnull == mImageGroup) {
// Create image group
nsresult rv = NS_NewImageGroup(&mImageGroup);
if (NS_OK != rv) {
return rv;
}
// Initialize the image group
nsIWidget* window;
nsIFrame* rootFrame;
rootFrame = mShell->GetRootFrame();
rootFrame->GetWindow(window);
nsIRenderingContext* drawCtx = window->GetRenderingContext();
drawCtx->Scale(mDeviceContext->GetAppUnitsToDevUnits(),
mDeviceContext->GetAppUnitsToDevUnits());
rv = mImageGroup->Init(drawCtx);
NS_RELEASE(drawCtx);
if (NS_OK != rv) {
return rv;
}
}
aGroupResult = mImageGroup;
NS_IF_ADDREF(mImageGroup);
return NS_OK;
}
NS_METHOD
nsPresContext::LoadImage(const nsString& aURL,
nsIFrame* aTargetFrame,
PRBool aNeedSizeUpdate,
nsIFrameImageLoader*& aLoaderResult)
{
aLoaderResult = nsnull;
// Lookup image request in our loaders array. Note that we need
// to get a loader that is observing the same image and that has
// the same value for aNeedSizeUpdate.
PRInt32 i, n = mImageLoaders.Count();
nsIFrameImageLoader* loader;
nsAutoString loaderURL;
for (i = 0; i < n; i++) {
loader = (nsIFrameImageLoader*) mImageLoaders.ElementAt(i);
nsIFrame* targetFrame;
loader->GetTargetFrame(targetFrame);
if (targetFrame == aTargetFrame) {
loader->GetURL(loaderURL);
// XXX case doesn't matter for all of the url so using Equals
// isn't quite right
if (aURL.Equals(loaderURL)) {
// Make sure the size update flags are the same, if not keep looking
PRIntn status;
loader->GetImageLoadStatus(status);
PRBool wantSize = 0 != (status & NS_IMAGE_LOAD_STATUS_SIZE_REQUESTED);
if (aNeedSizeUpdate == wantSize) {
NS_ADDREF(loader);
aLoaderResult = loader;
return NS_OK;
}
}
}
}
// Create image group if needed
nsresult rv;
if (nsnull == mImageGroup) {
nsIImageGroup* group;
rv = GetImageGroup(group);
if (NS_OK != rv) {
return rv;
}
}
// We haven't seen that image before. Create a new loader and
// start it going.
rv = NS_NewFrameImageLoader(&loader);
if (NS_OK != rv) {
return rv;
}
rv = loader->Init(this, mImageGroup, aURL, aTargetFrame, aNeedSizeUpdate);
if (NS_OK != rv) {
return rv;
}
mImageLoaders.AppendElement(loader);
// Return new loader
NS_ADDREF(loader);
aLoaderResult = loader;
return NS_OK;
}
NS_METHOD
nsPresContext::StopLoadImage(nsIFrame* aForFrame)
{
nsIFrameImageLoader* loader;
PRInt32 i, n = mImageLoaders.Count();
for (i = 0; i < n;) {
loader = (nsIFrameImageLoader*) mImageLoaders.ElementAt(i);
nsIFrame* loaderFrame;
loader->GetTargetFrame(loaderFrame);
if (loaderFrame == aForFrame) {
#ifdef NOISY_IMAGES
printf("%p: removing %p\n", this, aForFrame);
#endif
loader->StopImageLoad();
NS_RELEASE(loader);
mImageLoaders.RemoveElementAt(i);
n--;
continue;
}
i++;
}
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetLinkHandler(nsILinkHandler* aHandler)
{ // XXX should probably be a WEAK reference
NS_IF_RELEASE(mLinkHandler);
mLinkHandler = aHandler;
NS_IF_ADDREF(aHandler);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetLinkHandler(nsILinkHandler** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mLinkHandler;
NS_IF_ADDREF(mLinkHandler);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetContainer(nsISupports* aHandler)
{ // XXX should most likely be a WEAK reference
NS_IF_RELEASE(mContainer);
mContainer = aHandler;
NS_IF_ADDREF(aHandler);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetContainer(nsISupports** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mContainer;
NS_IF_ADDREF(mContainer);
return NS_OK;
}