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pjs/layout/base/nsPresContext.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 "nsPresContext.h"
#include "nsIPresShell.h"
#include "nsIPref.h"
#include "nsILinkHandler.h"
#include "nsIStyleSet.h"
#include "nsFrameImageLoader.h"
#include "nsIImageGroup.h"
#include "nsIFrame.h"
#include "nsIRenderingContext.h"
#include "nsEventStateManager.h"
#include "nsIURL.h"
#include "nsIURLGroup.h"
#include "nsIDocument.h"
#include "nsIFrame.h"
#include "nsIStyleContext.h"
#include "nsLayoutAtoms.h"
#ifdef _WIN32
#include <windows.h>
#endif
#ifdef DEBUG
#undef NOISY_IMAGES
#else
#undef NOISY_IMAGES
#endif
int
PrefChangedCallback(const char* aPrefName, void* instance_data)
{
nsPresContext* presContext = (nsPresContext*)instance_data;
NS_ASSERTION(nsnull != presContext, "bad instance data");
if (nsnull != presContext) {
presContext->PreferenceChanged(aPrefName);
}
return 0; // PREF_OK
}
static NS_DEFINE_IID(kIPresContextIID, NS_IPRESCONTEXT_IID);
nsPresContext::nsPresContext()
: mDefaultFont("Times", NS_FONT_STYLE_NORMAL,
NS_FONT_VARIANT_NORMAL,
NS_FONT_WEIGHT_NORMAL,
0,
NSIntPointsToTwips(12)),
mDefaultFixedFont("Courier", NS_FONT_STYLE_NORMAL,
NS_FONT_VARIANT_NORMAL,
NS_FONT_WEIGHT_NORMAL,
0,
NSIntPointsToTwips(10))
{
NS_INIT_REFCNT();
nsLayoutAtoms::AddrefAtoms();
mCompatibilityMode = eCompatibility_NavQuirks;
#ifdef _WIN32
// XXX This needs to be elsewhere, e.g., part of nsIDeviceContext
mDefaultColor = ::GetSysColor(COLOR_WINDOWTEXT);
mDefaultBackgroundColor = ::GetSysColor(COLOR_WINDOW);
#else
mDefaultColor = NS_RGB(0x00, 0x00, 0x00);
mDefaultBackgroundColor = NS_RGB(0xFF, 0xFF, 0xFF);
#endif
}
nsPresContext::~nsPresContext()
{
mShell = nsnull;
Stop();
if (nsnull != mImageGroup) {
// Interrupt any loading images. This also stops all looping
// image animations.
mImageGroup->Interrupt();
NS_RELEASE(mImageGroup);
}
NS_IF_RELEASE(mLinkHandler);
NS_IF_RELEASE(mContainer);
if (nsnull != mEventManager) {
mEventManager->SetPresContext(nsnull);
NS_RELEASE(mEventManager);
}
NS_IF_RELEASE(mDeviceContext);
// Unregister preference callbacks
if (nsnull != mPrefs) {
mPrefs->UnregisterCallback("browser.", PrefChangedCallback, (void*)this);
mPrefs->UnregisterCallback("intl.font2.", PrefChangedCallback, (void*)this);
}
NS_IF_RELEASE(mPrefs);
NS_IF_RELEASE(mBaseURL);
nsLayoutAtoms::ReleaseAtoms();
}
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);
void
nsPresContext::GetUserPreferences()
{
int32 prefInt;
char prefChar[512];
int charSize = sizeof(prefChar);
if (NS_OK == mPrefs->GetIntPref("browser.base_font_scaler", &prefInt)) {
mFontScaler = prefInt;
}
if (NS_OK == mPrefs->GetIntPref("intl.character_set", &prefInt)) {
prefInt &= 0x07ff;
} else {
prefInt = 2;
}
nsAutoString startKey("intl.font");
startKey.Append((PRInt32)prefInt, 10);
char keychar[256];
// XXX these font prefs strings don't take font encoding into account
// with the following change, it will depend on the intl.character_set to load the font face name and size
// It still need to be improve, but now QA can have change the intl.character_set value to switch different default font face
nsAutoString key(startKey);
key.Append(".win.prop_font");
key.ToCString(keychar, 256);
if (NS_OK == mPrefs->GetCharPref(keychar, &(prefChar[0]), &charSize)) {
mDefaultFont.name = prefChar;
}
key = startKey;
key.Append(".win.prop_size");
key.ToCString(keychar, 256);
if (NS_OK == mPrefs->GetIntPref(keychar, &prefInt)) {
mDefaultFont.size = NSIntPointsToTwips(prefInt);
}
key = startKey;
key.Append(".win.fixed_font");
key.ToCString(keychar, 256);
if (NS_OK == mPrefs->GetCharPref(keychar, &(prefChar[0]), &charSize)) {
mDefaultFixedFont.name = prefChar;
}
key = startKey;
key.Append(".win.fixed_size");
key.ToCString(keychar, 256);
if (NS_OK == mPrefs->GetIntPref(keychar, &prefInt)) {
mDefaultFixedFont.size = NSIntPointsToTwips(prefInt);
}
if (NS_OK == mPrefs->GetIntPref("nglayout.compatibility.mode", &prefInt)) {
mCompatibilityMode = (enum nsCompatibility)prefInt; // bad cast
}
PRBool usePrefColors = PR_TRUE;
#ifdef _WIN32
XP_Bool boolPref;
// XXX Is Windows the only platform that uses this?
if (NS_OK == mPrefs->GetBoolPref("browser.wfe.use_windows_colors", &boolPref)) {
usePrefColors = !PRBool(boolPref);
}
#endif
if (usePrefColors) {
uint32 colorPref;
if (NS_OK == mPrefs->GetColorPrefDWord("browser.foreground_color", &colorPref)) {
mDefaultColor = (nscolor)colorPref;
}
if (NS_OK == mPrefs->GetColorPrefDWord("browser.background_color", &colorPref)) {
mDefaultBackgroundColor = (nscolor)colorPref;
}
}
}
void
nsPresContext::PreferenceChanged(const char* aPrefName)
{
// Initialize our state from the user preferences
GetUserPreferences();
// Have the root frame's style context remap its style based on the
// user preferences
nsIFrame* rootFrame;
nsIStyleContext* rootStyleContext;
mShell->GetRootFrame(&rootFrame);
if (nsnull != rootFrame) {
rootFrame->GetStyleContext(&rootStyleContext);
rootStyleContext->RemapStyle(this);
NS_RELEASE(rootStyleContext);
// Force a reflow of the root frame
// XXX We really should only do a reflow if a preference that affects
// formatting changed, e.g., a font change. If it's just a color change
// then we only need to repaint...
mShell->StyleChangeReflow();
}
}
NS_IMETHODIMP
nsPresContext::Init(nsIDeviceContext* aDeviceContext, nsIPref* aPrefs)
{
NS_ASSERTION(!(mInitialized == PR_TRUE), "attempt to reinit pres context");
mDeviceContext = aDeviceContext;
NS_IF_ADDREF(mDeviceContext);
mPrefs = aPrefs;
NS_IF_ADDREF(mPrefs);
if (nsnull != mPrefs) {
// Register callbacks so we're notified when the preferences change
mPrefs->RegisterCallback("browser.", PrefChangedCallback, (void*)this);
mPrefs->RegisterCallback("intl.font2.", PrefChangedCallback, (void*)this);
// Initialize our state from the user preferences
GetUserPreferences();
}
#ifdef DEBUG
mInitialized = PR_TRUE;
#endif
return NS_OK;
}
// Note: We don't hold a reference on the shell; it has a reference to
// us
NS_IMETHODIMP
nsPresContext::SetShell(nsIPresShell* aShell)
{
NS_IF_RELEASE(mBaseURL);
mShell = aShell;
if (nsnull != mShell) {
nsCOMPtr<nsIDocument> doc;
if (NS_SUCCEEDED(mShell->GetDocument(getter_AddRefs(doc)))) {
NS_ASSERTION(doc, "expect document here");
if (doc) {
doc->GetBaseURL(mBaseURL);
}
}
}
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetShell(nsIPresShell** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mShell;
NS_IF_ADDREF(mShell);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetPrefs(nsIPref** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mPrefs;
NS_IF_ADDREF(mPrefs);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetCompatibilityMode(nsCompatibility* aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mCompatibilityMode;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetCompatibilityMode(nsCompatibility aMode)
{
mCompatibilityMode = aMode;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetBaseURL(nsIURL** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mBaseURL;
NS_IF_ADDREF(mBaseURL);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::ResolveStyleContextFor(nsIContent* aContent,
nsIStyleContext* aParentContext,
PRBool aForceUnique,
nsIStyleContext** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
nsIStyleContext* result = nsnull;
nsCOMPtr<nsIStyleSet> set;
nsresult rv = mShell->GetStyleSet(getter_AddRefs(set));
if (NS_SUCCEEDED(rv)) {
if (set) {
result = set->ResolveStyleFor(this, aContent, aParentContext,
aForceUnique);
if (nsnull == result) {
rv = NS_ERROR_OUT_OF_MEMORY;
}
}
}
*aResult = result;
return rv;
}
NS_IMETHODIMP
nsPresContext::ResolvePseudoStyleContextFor(nsIContent* aParentContent,
nsIAtom* aPseudoTag,
nsIStyleContext* aParentContext,
PRBool aForceUnique,
nsIStyleContext** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
nsIStyleContext* result = nsnull;
nsCOMPtr<nsIStyleSet> set;
nsresult rv = mShell->GetStyleSet(getter_AddRefs(set));
if (NS_SUCCEEDED(rv)) {
if (set) {
result = set->ResolvePseudoStyleFor(this, aParentContent, aPseudoTag,
aParentContext, aForceUnique);
if (nsnull == result) {
rv = NS_ERROR_OUT_OF_MEMORY;
}
}
}
*aResult = result;
return rv;
}
NS_IMETHODIMP
nsPresContext::ProbePseudoStyleContextFor(nsIContent* aParentContent,
nsIAtom* aPseudoTag,
nsIStyleContext* aParentContext,
PRBool aForceUnique,
nsIStyleContext** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
nsIStyleContext* result = nsnull;
nsCOMPtr<nsIStyleSet> set;
nsresult rv = mShell->GetStyleSet(getter_AddRefs(set));
if (NS_SUCCEEDED(rv)) {
if (set) {
result = set->ProbePseudoStyleFor(this, aParentContent, aPseudoTag,
aParentContext, aForceUnique);
}
}
*aResult = result;
return rv;
}
NS_IMETHODIMP
nsPresContext::GetMetricsFor(const nsFont& aFont, nsIFontMetrics** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
nsIFontMetrics* metrics = nsnull;
if (nsnull != mDeviceContext) {
mDeviceContext->GetMetricsFor(aFont, metrics);
}
*aResult = metrics;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetDefaultFont(nsFont& aResult)
{
aResult = mDefaultFont;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetDefaultFixedFont(nsFont& aResult)
{
aResult = mDefaultFixedFont;
return NS_OK;
}
const nsFont&
nsPresContext::GetDefaultFontDeprecated()
{
return mDefaultFont;
}
const nsFont&
nsPresContext::GetDefaultFixedFontDeprecated()
{
return mDefaultFixedFont;
}
NS_IMETHODIMP
nsPresContext::GetFontScaler(PRInt32* aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mFontScaler;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetFontScaler(PRInt32 aScaler)
{
mFontScaler = aScaler;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetDefaultColor(nscolor* aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mDefaultColor;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetDefaultBackgroundColor(nscolor* aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mDefaultBackgroundColor;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetDefaultColor(nscolor aColor)
{
mDefaultColor = aColor;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetDefaultBackgroundColor(nscolor aColor)
{
mDefaultBackgroundColor = aColor;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetVisibleArea(nsRect& aResult)
{
aResult = mVisibleArea;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::SetVisibleArea(const nsRect& r)
{
mVisibleArea = r;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetPixelsToTwips(float* aResult) const
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
float p2t = 1.0f;
if (nsnull != mDeviceContext) {
mDeviceContext->GetDevUnitsToAppUnits(p2t);
}
*aResult = p2t;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetTwipsToPixels(float* aResult) const
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
float app2dev = 1.0f;
if (nsnull != mDeviceContext) {
mDeviceContext->GetAppUnitsToDevUnits(app2dev);
}
*aResult = app2dev;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetScaledPixelsToTwips(float* aResult) const
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
float scale = 1.0f;
if (nsnull != mDeviceContext)
{
float p2t;
mDeviceContext->GetDevUnitsToAppUnits(p2t);
mDeviceContext->GetCanonicalPixelScale(scale);
scale = p2t * scale;
}
*aResult = scale;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetDeviceContext(nsIDeviceContext** aResult) const
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
*aResult = mDeviceContext;
NS_IF_ADDREF(mDeviceContext);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::GetImageGroup(nsIImageGroup** aResult)
{
NS_PRECONDITION(nsnull != aResult, "null ptr");
if (nsnull == aResult) {
return NS_ERROR_NULL_POINTER;
}
if (nsnull == mImageGroup) {
// Create image group
nsresult rv = NS_NewImageGroup(&mImageGroup);
if (NS_OK != rv) {
return rv;
}
// Initialize the image group
nsIURLGroup* urlGroup;
rv = mBaseURL->GetURLGroup(&urlGroup);
if (rv == NS_OK)
rv = mImageGroup->Init(mDeviceContext, urlGroup);
NS_IF_RELEASE(urlGroup);
if (NS_OK != rv) {
return rv;
}
}
*aResult = mImageGroup;
NS_IF_ADDREF(mImageGroup);
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::StartLoadImage(const nsString& aURL,
const nscolor* aBackgroundColor,
nsIFrame* aTargetFrame,
nsFrameImageLoaderCB aCallBack,
PRBool aNeedSizeUpdate,
PRBool aNeedErrorNotification,
nsIFrameImageLoader** aLoaderResult)
{
if (mStopped) {
return NS_OK;
}
#ifdef NOISY_IMAGES
nsIDocument* doc = mShell->GetDocument();
if (nsnull != doc) {
nsIURL* url = doc->GetDocumentURL();
if (nsnull != url) {
printf("%s: ", url->GetSpec());
NS_RELEASE(url);
}
NS_RELEASE(doc);
}
printf("%p: start load for %p (", this, aTargetFrame);
fputs(aURL, stdout);
printf(")\n");
#endif
*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) {
nsCOMPtr<nsIImageGroup> group;
rv = GetImageGroup(getter_AddRefs(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;
}
mImageLoaders.AppendElement(loader);
rv = loader->Init(this, mImageGroup, aURL, aBackgroundColor, aTargetFrame,
aCallBack, aNeedSizeUpdate, aNeedErrorNotification);
if (NS_OK != rv) {
mImageLoaders.RemoveElement(loader);
NS_RELEASE(loader);
return rv;
}
// Return the loader
NS_ADDREF(loader);
*aLoaderResult = loader;
return NS_OK;
}
NS_IMETHODIMP
nsPresContext::Stop(void)
{
PRInt32 n = mImageLoaders.Count();
for (PRInt32 i = 0; i < n; i++) {
nsIFrameImageLoader* loader;
loader = (nsIFrameImageLoader*) mImageLoaders.ElementAt(i);
loader->StopImageLoad();
NS_RELEASE(loader);
}
mImageLoaders.Clear();
mStopped = PR_TRUE;
return NS_OK;
}
NS_IMETHODIMP
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
nsIDocument* doc = mShell->GetDocument();
if (nsnull != doc) {
nsIURL* url = doc->GetDocumentURL();
if (nsnull != url) {
printf("%s: ", url->GetSpec());
NS_RELEASE(url);
}
NS_RELEASE(doc);
}
printf("%p: stop load for %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;
}
NS_IMETHODIMP
nsPresContext::GetEventStateManager(nsIEventStateManager** aManager)
{
NS_PRECONDITION(nsnull != aManager, "null ptr");
if (nsnull == aManager) {
return NS_ERROR_NULL_POINTER;
}
if (nsnull == mEventManager) {
nsresult rv = NS_NewEventStateManager(&mEventManager);
if (NS_OK != rv) {
return rv;
}
}
//Not refcnted, set null in destructor
mEventManager->SetPresContext(this);
*aManager = mEventManager;
NS_IF_ADDREF(mEventManager);
return NS_OK;
}
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