gecko-dev/layout/style/nsTransitionManager.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla 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/MPL/
*
* 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 nsTransitionManager.
*
* The Initial Developer of the Original Code is the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* L. David Baron <dbaron@dbaron.org>, Mozilla Corporation (original author)
*
* 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 MPL, 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 MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* Code to start and animate CSS transitions. */
#include "nsTransitionManager.h"
#include "nsIContent.h"
#include "nsStyleContext.h"
#include "nsCSSProps.h"
#include "mozilla/TimeStamp.h"
#include "nsRefreshDriver.h"
#include "nsRuleProcessorData.h"
#include "nsIStyleRule.h"
#include "nsRuleWalker.h"
#include "nsRuleData.h"
#include "nsSMILKeySpline.h"
#include "gfxColor.h"
#include "nsCSSPropertySet.h"
#include "nsStyleAnimation.h"
#include "nsEventDispatcher.h"
#include "nsGUIEvent.h"
#include "mozilla/dom/Element.h"
using mozilla::TimeStamp;
using mozilla::TimeDuration;
namespace dom = mozilla::dom;
/*****************************************************************************
* Per-Element data *
*****************************************************************************/
struct ElementPropertyTransition
{
nsCSSProperty mProperty;
nsStyleAnimation::Value mStartValue, mEndValue;
TimeStamp mStartTime; // actual start plus transition delay
// data from the relevant nsTransition
TimeDuration mDuration;
nsSMILKeySpline mTimingFunction;
// This is the start value to be used for a check for whether a
// transition is being reversed. Normally the same as mStartValue,
// except when this transition started as the reversal of another
// in-progress transition. Needed so we can handle two reverses in a
// row.
nsStyleAnimation::Value mStartForReversingTest;
// Likewise, the portion (in value space) of the "full" reversed
// transition that we're actually covering. For example, if a :hover
// effect has a transition that moves the element 10px to the right
// (by changing 'left' from 0px to 10px), and the mouse moves in to
// the element (starting the transition) but then moves out after the
// transition has advanced 4px, the second transition (from 10px/4px
// to 0px) will have mReversePortion of 0.4. (If the mouse then moves
// in again when the transition is back to 2px, the mReversePortion
// for the third transition (from 0px/2px to 10px) will be 0.8.
double mReversePortion;
// Compute the portion of the *value* space that we should be through
// at the given time. (The input to the transition timing function
// has time units, the output has value units.)
double ValuePortionFor(TimeStamp aRefreshTime) const;
PRBool IsRemovedSentinel() const
{
return mStartTime.IsNull();
}
void SetRemovedSentinel()
{
// assign the null time stamp
mStartTime = TimeStamp();
}
};
double
ElementPropertyTransition::ValuePortionFor(TimeStamp aRefreshTime) const
{
// Set |timePortion| to the portion of the way we are through the time
// input to the transition's timing function (always within the range
// 0-1).
double duration = mDuration.ToSeconds();
NS_ABORT_IF_FALSE(duration >= 0.0, "negative duration forbidden");
double timePortion;
if (duration == 0.0) {
// When duration is zero, we can still have a transition when delay
// is nonzero. mStartTime already incorporates delay.
if (aRefreshTime >= mStartTime) {
timePortion = 1.0;
} else {
timePortion = 0.0;
}
} else {
timePortion = (aRefreshTime - mStartTime).ToSeconds() / duration;
if (timePortion < 0.0)
timePortion = 0.0; // use start value during transition-delay
if (timePortion > 1.0)
timePortion = 1.0; // we might be behind on flushing
}
return mTimingFunction.GetSplineValue(timePortion);
}
/**
* A style rule that maps property-nsStyleAnimation::Value pairs.
*/
class AnimValuesStyleRule : public nsIStyleRule
{
public:
// nsISupports implementation
NS_DECL_ISUPPORTS
// nsIStyleRule implementation
virtual void MapRuleInfoInto(nsRuleData* aRuleData);
#ifdef DEBUG
virtual void List(FILE* out = stdout, PRInt32 aIndent = 0) const;
#endif
void AddValue(nsCSSProperty aProperty, nsStyleAnimation::Value &aStartValue)
{
PropertyValuePair v = { aProperty, aStartValue };
mPropertyValuePairs.AppendElement(v);
}
// Caller must fill in returned value, when non-null.
nsStyleAnimation::Value* AddEmptyValue(nsCSSProperty aProperty)
{
PropertyValuePair *p = mPropertyValuePairs.AppendElement();
if (!p) {
return nsnull;
}
p->mProperty = aProperty;
return &p->mValue;
}
struct PropertyValuePair {
nsCSSProperty mProperty;
nsStyleAnimation::Value mValue;
};
private:
nsTArray<PropertyValuePair> mPropertyValuePairs;
};
struct ElementTransitions : public PRCList
{
ElementTransitions(dom::Element *aElement, nsIAtom *aElementProperty,
nsTransitionManager *aTransitionManager)
: mElement(aElement)
, mElementProperty(aElementProperty)
, mTransitionManager(aTransitionManager)
{
PR_INIT_CLIST(this);
}
~ElementTransitions()
{
PR_REMOVE_LINK(this);
mTransitionManager->TransitionsRemoved();
}
void Destroy()
{
// This will call our destructor.
mElement->DeleteProperty(mElementProperty);
}
void EnsureStyleRuleFor(TimeStamp aRefreshTime);
// Either zero or one for each CSS property:
nsTArray<ElementPropertyTransition> mPropertyTransitions;
// This style rule overrides style data with the currently
// transitioning value for an element that is executing a transition.
// It only matches when styling with animation. When we style without
// animation, we need to not use it so that we can detect any new
// changes; if necessary we restyle immediately afterwards with
// animation.
nsRefPtr<AnimValuesStyleRule> mStyleRule;
// The refresh time associated with mStyleRule.
TimeStamp mStyleRuleRefreshTime;
dom::Element *mElement;
// the atom we use in mElement's prop table (must be a static atom,
// i.e., in an atom list)
nsIAtom *mElementProperty;
nsTransitionManager *mTransitionManager;
};
static void
ElementTransitionsPropertyDtor(void *aObject,
nsIAtom *aPropertyName,
void *aPropertyValue,
void *aData)
{
ElementTransitions *et = static_cast<ElementTransitions*>(aPropertyValue);
delete et;
}
void
ElementTransitions::EnsureStyleRuleFor(TimeStamp aRefreshTime)
{
if (!mStyleRule || mStyleRuleRefreshTime != aRefreshTime) {
mStyleRule = new AnimValuesStyleRule();
mStyleRuleRefreshTime = aRefreshTime;
for (PRUint32 i = 0, i_end = mPropertyTransitions.Length(); i < i_end; ++i)
{
ElementPropertyTransition &pt = mPropertyTransitions[i];
if (pt.IsRemovedSentinel()) {
continue;
}
nsStyleAnimation::Value *val = mStyleRule->AddEmptyValue(pt.mProperty);
if (!val) {
continue;
}
double valuePortion = pt.ValuePortionFor(aRefreshTime);
#ifdef DEBUG
PRBool ok =
#endif
nsStyleAnimation::Interpolate(pt.mProperty,
pt.mStartValue, pt.mEndValue,
valuePortion, *val);
NS_ABORT_IF_FALSE(ok, "could not interpolate values");
}
}
}
NS_IMPL_ISUPPORTS1(AnimValuesStyleRule, nsIStyleRule)
/* virtual */ void
AnimValuesStyleRule::MapRuleInfoInto(nsRuleData* aRuleData)
{
nsStyleContext *contextParent = aRuleData->mStyleContext->GetParent();
if (contextParent && contextParent->HasPseudoElementData()) {
// Don't apply transitions to things inside of pseudo-elements.
// FIXME (Bug 522599): Add tests for this.
return;
}
for (PRUint32 i = 0, i_end = mPropertyValuePairs.Length(); i < i_end; ++i) {
PropertyValuePair &cv = mPropertyValuePairs[i];
if (aRuleData->mSIDs & nsCachedStyleData::GetBitForSID(
nsCSSProps::kSIDTable[cv.mProperty]))
{
nsCSSValue *prop = aRuleData->ValueFor(cv.mProperty);
if (prop->GetUnit() == eCSSUnit_Null) {
#ifdef DEBUG
PRBool ok =
#endif
nsStyleAnimation::UncomputeValue(cv.mProperty,
aRuleData->mPresContext,
cv.mValue, *prop);
NS_ABORT_IF_FALSE(ok, "could not store computed value");
}
}
}
}
#ifdef DEBUG
/* virtual */ void
AnimValuesStyleRule::List(FILE* out, PRInt32 aIndent) const
{
// WRITE ME?
}
#endif
/*****************************************************************************
* nsTransitionManager *
*****************************************************************************/
nsTransitionManager::nsTransitionManager(nsPresContext *aPresContext)
: mPresContext(aPresContext)
{
PR_INIT_CLIST(&mElementTransitions);
}
nsTransitionManager::~nsTransitionManager()
{
NS_ABORT_IF_FALSE(!mPresContext, "Disconnect should have been called");
}
void
nsTransitionManager::Disconnect()
{
// Content nodes might outlive the transition manager.
RemoveAllTransitions();
mPresContext = nsnull;
}
void
nsTransitionManager::RemoveAllTransitions()
{
while (!PR_CLIST_IS_EMPTY(&mElementTransitions)) {
ElementTransitions *head = static_cast<ElementTransitions*>(
PR_LIST_HEAD(&mElementTransitions));
head->Destroy();
}
}
static PRBool
TransExtractComputedValue(nsCSSProperty aProperty,
nsStyleContext* aStyleContext,
nsStyleAnimation::Value& aComputedValue)
{
PRBool result =
nsStyleAnimation::ExtractComputedValue(aProperty, aStyleContext,
aComputedValue);
if (aProperty == eCSSProperty_visibility) {
NS_ABORT_IF_FALSE(aComputedValue.GetUnit() ==
nsStyleAnimation::eUnit_Enumerated,
"unexpected unit");
aComputedValue.SetIntValue(aComputedValue.GetIntValue(),
nsStyleAnimation::eUnit_Visibility);
}
return result;
}
already_AddRefed<nsIStyleRule>
nsTransitionManager::StyleContextChanged(dom::Element *aElement,
nsStyleContext *aOldStyleContext,
nsStyleContext *aNewStyleContext)
{
NS_PRECONDITION(aOldStyleContext->GetPseudo() ==
aNewStyleContext->GetPseudo(),
"pseudo type mismatch");
// If we were called from ReparentStyleContext, this assertion would
// actually fire. If we need to be called from there, we can probably
// just remove it; the condition probably isn't critical, although
// it's worth thinking about some more.
NS_PRECONDITION(aOldStyleContext->HasPseudoElementData() ==
aNewStyleContext->HasPseudoElementData(),
"pseudo type mismatch");
// NOTE: Things in this function (and ConsiderStartingTransition)
// should never call PeekStyleData because we don't preserve gotten
// structs across reframes.
// Return sooner (before the startedAny check below) for the most
// common case: no transitions specified or running.
const nsStyleDisplay *disp = aNewStyleContext->GetStyleDisplay();
nsCSSPseudoElements::Type pseudoType = aNewStyleContext->GetPseudoType();
if (pseudoType != nsCSSPseudoElements::ePseudo_NotPseudoElement) {
if (pseudoType != nsCSSPseudoElements::ePseudo_before &&
pseudoType != nsCSSPseudoElements::ePseudo_after) {
return nsnull;
}
NS_ASSERTION((pseudoType == nsCSSPseudoElements::ePseudo_before &&
aElement->Tag() == nsGkAtoms::mozgeneratedcontentbefore) ||
(pseudoType == nsCSSPseudoElements::ePseudo_after &&
aElement->Tag() == nsGkAtoms::mozgeneratedcontentafter),
"Unexpected aElement coming through");
// Else the element we want to use from now on is the element the
// :before or :after is attached to.
aElement = aElement->GetParent()->AsElement();
}
ElementTransitions *et =
GetElementTransitions(aElement, pseudoType, PR_FALSE);
if (!et &&
disp->mTransitionPropertyCount == 1 &&
disp->mTransitions[0].GetDelay() == 0.0f &&
disp->mTransitions[0].GetDuration() == 0.0f) {
return nsnull;
}
if (aNewStyleContext->PresContext()->IsProcessingAnimationStyleChange()) {
return nsnull;
}
if (aNewStyleContext->GetParent() &&
aNewStyleContext->GetParent()->HasPseudoElementData()) {
// Ignore transitions on things that inherit properties from
// pseudo-elements.
// FIXME (Bug 522599): Add tests for this.
return nsnull;
}
// Per http://lists.w3.org/Archives/Public/www-style/2009Aug/0109.html
// I'll consider only the transitions from the number of items in
// 'transition-property' on down, and later ones will override earlier
// ones (tracked using |whichStarted|).
PRBool startedAny = PR_FALSE;
nsCSSPropertySet whichStarted;
for (PRUint32 i = disp->mTransitionPropertyCount; i-- != 0; ) {
const nsTransition& t = disp->mTransitions[i];
// Check delay and duration first, since they default to zero, and
// when they're both zero, we can ignore the transition.
if (t.GetDelay() != 0.0f || t.GetDuration() != 0.0f) {
// We might have something to transition. See if any of the
// properties in question changed and are animatable.
// FIXME: Would be good to find a way to share code between this
// interpretation of transition-property and the one below.
nsCSSProperty property = t.GetProperty();
if (property == eCSSPropertyExtra_no_properties ||
property == eCSSProperty_UNKNOWN) {
// Nothing to do, but need to exclude this from cases below.
} else if (property == eCSSPropertyExtra_all_properties) {
for (nsCSSProperty p = nsCSSProperty(0);
p < eCSSProperty_COUNT_no_shorthands;
p = nsCSSProperty(p + 1)) {
ConsiderStartingTransition(p, t, aElement, et,
aOldStyleContext, aNewStyleContext,
&startedAny, &whichStarted);
}
} else if (nsCSSProps::IsShorthand(property)) {
CSSPROPS_FOR_SHORTHAND_SUBPROPERTIES(subprop, property) {
ConsiderStartingTransition(*subprop, t, aElement, et,
aOldStyleContext, aNewStyleContext,
&startedAny, &whichStarted);
}
} else {
ConsiderStartingTransition(property, t, aElement, et,
aOldStyleContext, aNewStyleContext,
&startedAny, &whichStarted);
}
}
}
// Stop any transitions for properties that are no longer in
// 'transition-property'.
// Also stop any transitions for properties that just changed (and are
// still in the set of properties to transition), but we didn't just
// start the transition because delay and duration are both zero.
if (et) {
PRBool checkProperties =
disp->mTransitions[0].GetProperty() != eCSSPropertyExtra_all_properties;
nsCSSPropertySet allTransitionProperties;
if (checkProperties) {
for (PRUint32 i = disp->mTransitionPropertyCount; i-- != 0; ) {
const nsTransition& t = disp->mTransitions[i];
// FIXME: Would be good to find a way to share code between this
// interpretation of transition-property and the one above.
nsCSSProperty property = t.GetProperty();
if (property == eCSSPropertyExtra_no_properties ||
property == eCSSProperty_UNKNOWN) {
// Nothing to do, but need to exclude this from cases below.
} else if (property == eCSSPropertyExtra_all_properties) {
for (nsCSSProperty p = nsCSSProperty(0);
p < eCSSProperty_COUNT_no_shorthands;
p = nsCSSProperty(p + 1)) {
allTransitionProperties.AddProperty(p);
}
} else if (nsCSSProps::IsShorthand(property)) {
CSSPROPS_FOR_SHORTHAND_SUBPROPERTIES(subprop, property) {
allTransitionProperties.AddProperty(*subprop);
}
} else {
allTransitionProperties.AddProperty(property);
}
}
}
nsTArray<ElementPropertyTransition> &pts = et->mPropertyTransitions;
PRUint32 i = pts.Length();
NS_ABORT_IF_FALSE(i != 0, "empty transitions list?");
nsStyleAnimation::Value currentValue;
do {
--i;
ElementPropertyTransition &pt = pts[i];
// properties no longer in 'transition-property'
if ((checkProperties &&
!allTransitionProperties.HasProperty(pt.mProperty)) ||
// properties whose computed values changed but delay and
// duration are both zero
!TransExtractComputedValue(pt.mProperty, aNewStyleContext,
currentValue) ||
currentValue != pt.mEndValue) {
// stop the transition
pts.RemoveElementAt(i);
}
} while (i != 0);
if (pts.IsEmpty()) {
et->Destroy();
et = nsnull;
}
}
if (!startedAny) {
return nsnull;
}
NS_ABORT_IF_FALSE(et, "must have element transitions if we started "
"any transitions");
// In the CSS working group discussion (2009 Jul 15 telecon,
// http://www.w3.org/mid/4A5E1470.4030904@inkedblade.net ) of
// http://lists.w3.org/Archives/Public/www-style/2009Jun/0121.html ,
// the working group decided that a transition property on an
// element should not cause any transitions if the property change
// is itself inheriting a value that is transitioning on an
// ancestor. So, to get the correct behavior, we continue the
// restyle that caused this transition using a "covering" rule that
// covers up any changes on which we started transitions, so that
// descendants don't start their own transitions. (In the case of
// negative transition delay, this covering rule produces different
// results than applying the transition rule immediately would).
// Our caller is responsible for restyling again using this covering
// rule.
nsRefPtr<AnimValuesStyleRule> coverRule = new AnimValuesStyleRule;
if (!coverRule) {
NS_WARNING("out of memory");
return nsnull;
}
nsTArray<ElementPropertyTransition> &pts = et->mPropertyTransitions;
for (PRUint32 i = 0, i_end = pts.Length(); i < i_end; ++i) {
ElementPropertyTransition &pt = pts[i];
if (whichStarted.HasProperty(pt.mProperty)) {
coverRule->AddValue(pt.mProperty, pt.mStartValue);
}
}
return coverRule.forget();
}
void
nsTransitionManager::ConsiderStartingTransition(nsCSSProperty aProperty,
const nsTransition& aTransition,
dom::Element *aElement,
ElementTransitions *&aElementTransitions,
nsStyleContext *aOldStyleContext,
nsStyleContext *aNewStyleContext,
PRBool *aStartedAny,
nsCSSPropertySet *aWhichStarted)
{
// IsShorthand itself will assert if aProperty is not a property.
NS_ABORT_IF_FALSE(!nsCSSProps::IsShorthand(aProperty),
"property out of range");
if (aWhichStarted->HasProperty(aProperty)) {
// A later item in transition-property already started a
// transition for this property, so we ignore this one.
// See comment above and
// http://lists.w3.org/Archives/Public/www-style/2009Aug/0109.html .
return;
}
if (nsCSSProps::kAnimTypeTable[aProperty] == eStyleAnimType_None) {
return;
}
ElementPropertyTransition pt;
nsStyleAnimation::Value dummyValue;
PRBool haveValues =
TransExtractComputedValue(aProperty, aOldStyleContext, pt.mStartValue) &&
TransExtractComputedValue(aProperty, aNewStyleContext, pt.mEndValue);
PRBool shouldAnimate =
haveValues &&
pt.mStartValue != pt.mEndValue &&
// Check that we can interpolate between these values
// (If this is ever a performance problem, we could add a
// CanInterpolate method, but it seems fine for now.)
nsStyleAnimation::Interpolate(aProperty, pt.mStartValue, pt.mEndValue,
0.5, dummyValue);
PRUint32 currentIndex = nsTArray<ElementPropertyTransition>::NoIndex;
if (aElementTransitions) {
nsTArray<ElementPropertyTransition> &pts =
aElementTransitions->mPropertyTransitions;
for (PRUint32 i = 0, i_end = pts.Length(); i < i_end; ++i) {
if (pts[i].mProperty == aProperty) {
currentIndex = i;
break;
}
}
}
nsPresContext *presContext = aNewStyleContext->PresContext();
if (!shouldAnimate) {
nsTArray<ElementPropertyTransition> &pts =
aElementTransitions->mPropertyTransitions;
if (currentIndex != nsTArray<ElementPropertyTransition>::NoIndex &&
(!haveValues || pts[currentIndex].mEndValue != pt.mEndValue)) {
// We're in the middle of a transition, but just got a
// non-transition style change changing to exactly the
// current in-progress value. (This is quite easy to cause
// using 'transition-delay'.)
//
// We also check that this current in-progress value is different
// from the end value; we don't want to cancel a transition that
// is almost done (and whose current value rounds to its end
// value) just because we got an unrelated style change.
pts.RemoveElementAt(currentIndex);
if (pts.IsEmpty()) {
aElementTransitions->Destroy();
// |aElementTransitions| is now a dangling pointer!
aElementTransitions = nsnull;
}
// WalkTransitionRule already called RestyleForAnimation.
}
return;
}
TimeStamp mostRecentRefresh =
presContext->RefreshDriver()->MostRecentRefresh();
const nsTimingFunction &tf = aTransition.GetTimingFunction();
float delay = aTransition.GetDelay();
float duration = aTransition.GetDuration();
if (duration < 0.0) {
// The spec says a negative duration is treated as zero.
duration = 0.0;
}
pt.mStartForReversingTest = pt.mStartValue;
pt.mReversePortion = 1.0;
// We need to check two things if we have a currently running
// transition for this property.
if (currentIndex != nsTArray<ElementPropertyTransition>::NoIndex) {
const ElementPropertyTransition &oldPT =
aElementTransitions->mPropertyTransitions[currentIndex];
if (oldPT.mEndValue == pt.mEndValue) {
// If we got a style change that changed the value to the endpoint
// of the currently running transition, we don't want to interrupt
// its timing function.
// WalkTransitionRule already called RestyleForAnimation.
return;
}
// If the new transition reverses the old one, we'll need to handle
// the timing differently.
if (!oldPT.IsRemovedSentinel() &&
oldPT.mStartForReversingTest == pt.mEndValue) {
// Compute the appropriate negative transition-delay such that right
// now we'd end up at the current position.
double valuePortion =
oldPT.ValuePortionFor(mostRecentRefresh) * oldPT.mReversePortion +
(1.0 - oldPT.mReversePortion);
// A timing function with negative y1 (or y2!) might make
// valuePortion negative. In this case, we still want to apply our
// reversing logic based on relative distances, not make duration
// negative.
if (valuePortion < 0.0)
valuePortion = -valuePortion;
// A timing function with y2 (or y1!) greater than one might
// advance past its terminal value. It's probably a good idea to
// clamp valuePortion to be at most one to preserve the invariant
// that a transition will complete within at most its specified
// time.
if (valuePortion > 1.0)
valuePortion = 1.0;
// Negative delays are essentially part of the transition
// function, so reduce them along with the duration, but don't
// reduce positive delays.
if (delay < 0.0f)
delay *= valuePortion;
duration *= valuePortion;
pt.mStartForReversingTest = oldPT.mEndValue;
pt.mReversePortion = valuePortion;
}
}
pt.mProperty = aProperty;
pt.mStartTime = mostRecentRefresh + TimeDuration::FromMilliseconds(delay);
pt.mDuration = TimeDuration::FromMilliseconds(duration);
pt.mTimingFunction.Init(tf.mX1, tf.mY1, tf.mX2, tf.mY2);
if (!aElementTransitions) {
aElementTransitions =
GetElementTransitions(aElement, aNewStyleContext->GetPseudoType(),
PR_TRUE);
if (!aElementTransitions) {
NS_WARNING("allocating ElementTransitions failed");
return;
}
}
nsTArray<ElementPropertyTransition> &pts =
aElementTransitions->mPropertyTransitions;
#ifdef DEBUG
for (PRUint32 i = 0, i_end = pts.Length(); i < i_end; ++i) {
NS_ABORT_IF_FALSE(i == currentIndex ||
pts[i].mProperty != aProperty,
"duplicate transitions for property");
}
#endif
if (currentIndex != nsTArray<ElementPropertyTransition>::NoIndex) {
pts[currentIndex] = pt;
} else {
if (!pts.AppendElement(pt)) {
NS_WARNING("out of memory");
return;
}
}
nsRestyleHint hint =
aNewStyleContext->GetPseudoType() ==
nsCSSPseudoElements::ePseudo_NotPseudoElement ?
eRestyle_Self : eRestyle_Subtree;
presContext->PresShell()->RestyleForAnimation(aElement, hint);
*aStartedAny = PR_TRUE;
aWhichStarted->AddProperty(aProperty);
}
ElementTransitions*
nsTransitionManager::GetElementTransitions(dom::Element *aElement,
nsCSSPseudoElements::Type aPseudoType,
PRBool aCreateIfNeeded)
{
if (!aCreateIfNeeded && PR_CLIST_IS_EMPTY(&mElementTransitions)) {
// Early return for the most common case.
return nsnull;
}
nsIAtom *propName;
if (aPseudoType == nsCSSPseudoElements::ePseudo_NotPseudoElement) {
propName = nsGkAtoms::transitionsProperty;
} else if (aPseudoType == nsCSSPseudoElements::ePseudo_before) {
propName = nsGkAtoms::transitionsOfBeforeProperty;
} else if (aPseudoType == nsCSSPseudoElements::ePseudo_after) {
propName = nsGkAtoms::transitionsOfAfterProperty;
} else {
NS_ASSERTION(!aCreateIfNeeded,
"should never try to create transitions for pseudo "
"other than :before or :after");
return nsnull;
}
ElementTransitions *et = static_cast<ElementTransitions*>(
aElement->GetProperty(propName));
if (!et && aCreateIfNeeded) {
// FIXME: Consider arena-allocating?
et = new ElementTransitions(aElement, propName, this);
if (!et) {
NS_WARNING("out of memory");
return nsnull;
}
nsresult rv = aElement->SetProperty(propName, et,
ElementTransitionsPropertyDtor, nsnull);
if (NS_FAILED(rv)) {
NS_WARNING("SetProperty failed");
delete et;
return nsnull;
}
AddElementTransitions(et);
}
return et;
}
void
nsTransitionManager::AddElementTransitions(ElementTransitions* aElementTransitions)
{
if (PR_CLIST_IS_EMPTY(&mElementTransitions)) {
// We need to observe the refresh driver.
nsRefreshDriver *rd = mPresContext->RefreshDriver();
rd->AddRefreshObserver(this, Flush_Style);
}
PR_INSERT_BEFORE(aElementTransitions, &mElementTransitions);
}
/*
* nsISupports implementation
*/
NS_IMPL_ISUPPORTS1(nsTransitionManager, nsIStyleRuleProcessor)
/*
* nsIStyleRuleProcessor implementation
*/
void
nsTransitionManager::WalkTransitionRule(RuleProcessorData* aData,
nsCSSPseudoElements::Type aPseudoType)
{
ElementTransitions *et =
GetElementTransitions(aData->mElement, aPseudoType, PR_FALSE);
if (!et) {
return;
}
if (aData->mPresContext->IsProcessingRestyles() &&
!aData->mPresContext->IsProcessingAnimationStyleChange()) {
// If we're processing a normal style change rather than one from
// animation, don't add the transition rule. This allows us to
// compute the new style value rather than having the transition
// override it, so that we can start transitioning differently.
// We need to immediately restyle with animation
// after doing this.
if (et) {
nsRestyleHint hint =
aPseudoType == nsCSSPseudoElements::ePseudo_NotPseudoElement ?
eRestyle_Self : eRestyle_Subtree;
mPresContext->PresShell()->RestyleForAnimation(aData->mElement, hint);
}
return;
}
et->EnsureStyleRuleFor(
aData->mPresContext->RefreshDriver()->MostRecentRefresh());
aData->mRuleWalker->Forward(et->mStyleRule);
}
/* virtual */ void
nsTransitionManager::RulesMatching(ElementRuleProcessorData* aData)
{
NS_ABORT_IF_FALSE(aData->mPresContext == mPresContext,
"pres context mismatch");
WalkTransitionRule(aData,
nsCSSPseudoElements::ePseudo_NotPseudoElement);
}
/* virtual */ void
nsTransitionManager::RulesMatching(PseudoElementRuleProcessorData* aData)
{
NS_ABORT_IF_FALSE(aData->mPresContext == mPresContext,
"pres context mismatch");
// Note: If we're the only thing keeping a pseudo-element frame alive
// (per ProbePseudoStyleContext), we still want to keep it alive, so
// this is ok.
WalkTransitionRule(aData, aData->mPseudoType);
}
/* virtual */ void
nsTransitionManager::RulesMatching(AnonBoxRuleProcessorData* aData)
{
}
#ifdef MOZ_XUL
/* virtual */ void
nsTransitionManager::RulesMatching(XULTreeRuleProcessorData* aData)
{
}
#endif
nsRestyleHint
nsTransitionManager::HasStateDependentStyle(StateRuleProcessorData* aData)
{
return nsRestyleHint(0);
}
PRBool
nsTransitionManager::HasDocumentStateDependentStyle(StateRuleProcessorData* aData)
{
return PR_FALSE;
}
nsRestyleHint
nsTransitionManager::HasAttributeDependentStyle(AttributeRuleProcessorData* aData)
{
return nsRestyleHint(0);
}
/* virtual */ PRBool
nsTransitionManager::MediumFeaturesChanged(nsPresContext* aPresContext)
{
return PR_FALSE;
}
struct TransitionEventInfo {
nsCOMPtr<nsIContent> mElement;
nsTransitionEvent mEvent;
TransitionEventInfo(nsIContent *aElement, nsCSSProperty aProperty,
TimeDuration aDuration)
: mElement(aElement),
mEvent(PR_TRUE, NS_TRANSITION_END,
NS_ConvertUTF8toUTF16(nsCSSProps::GetStringValue(aProperty)),
aDuration.ToSeconds())
{
}
// nsTransitionEvent doesn't support copy-construction, so we need
// to ourselves in order to work with nsTArray
TransitionEventInfo(const TransitionEventInfo &aOther)
: mElement(aOther.mElement),
mEvent(PR_TRUE, NS_TRANSITION_END,
aOther.mEvent.propertyName, aOther.mEvent.elapsedTime)
{
}
};
/* virtual */ void
nsTransitionManager::WillRefresh(mozilla::TimeStamp aTime)
{
NS_ABORT_IF_FALSE(mPresContext,
"refresh driver should not notify additional observers "
"after pres context has been destroyed");
if (!mPresContext->GetPresShell()) {
// Someone might be keeping mPresContext alive past the point
// where it has been torn down; don't bother doing anything in
// this case. But do get rid of all our transitions so we stop
// triggering refreshes.
RemoveAllTransitions();
return;
}
nsTArray<TransitionEventInfo> events;
// Trim transitions that have completed, and post restyle events for
// frames that are still transitioning.
{
PRCList *next = PR_LIST_HEAD(&mElementTransitions);
while (next != &mElementTransitions) {
ElementTransitions *et = static_cast<ElementTransitions*>(next);
next = PR_NEXT_LINK(next);
NS_ABORT_IF_FALSE(et->mElement->GetCurrentDoc() ==
mPresContext->Document(),
"nsGenericElement::UnbindFromTree should have "
"destroyed the element transitions object");
PRUint32 i = et->mPropertyTransitions.Length();
NS_ABORT_IF_FALSE(i != 0, "empty transitions list?");
do {
--i;
ElementPropertyTransition &pt = et->mPropertyTransitions[i];
if (pt.IsRemovedSentinel()) {
// Actually remove transitions one cycle after their
// completion. See comment below.
et->mPropertyTransitions.RemoveElementAt(i);
} else if (pt.mStartTime + pt.mDuration <= aTime) {
// This transition has completed.
// Fire transitionend events only for transitions on elements
// and not those on pseudo-elements, since we can't target an
// event at pseudo-elements.
if (et->mElementProperty == nsGkAtoms::transitionsProperty) {
nsCSSProperty prop = pt.mProperty;
if (nsCSSProps::PropHasFlags(prop, CSS_PROPERTY_REPORT_OTHER_NAME))
{
prop = nsCSSProps::OtherNameFor(prop);
}
events.AppendElement(
TransitionEventInfo(et->mElement, prop, pt.mDuration));
}
// Leave this transition in the list for one more refresh
// cycle, since we haven't yet processed its style change, and
// if we also have (already, or will have from processing
// transitionend events or other refresh driver notifications)
// a non-animation style change that would affect it, we need
// to know not to start a new transition for the transition
// from the almost-completed value to the final value.
pt.SetRemovedSentinel();
}
} while (i != 0);
// We need to restyle even if the transition rule no longer
// applies (in which case we just made it not apply).
NS_ASSERTION(et->mElementProperty == nsGkAtoms::transitionsProperty ||
et->mElementProperty == nsGkAtoms::transitionsOfBeforeProperty ||
et->mElementProperty == nsGkAtoms::transitionsOfAfterProperty,
"Unexpected element property; might restyle too much");
nsRestyleHint hint = et->mElementProperty == nsGkAtoms::transitionsProperty ?
eRestyle_Self : eRestyle_Subtree;
mPresContext->PresShell()->RestyleForAnimation(et->mElement, hint);
if (et->mPropertyTransitions.IsEmpty()) {
et->Destroy();
// |et| is now a dangling pointer!
et = nsnull;
}
}
}
// We might have removed transitions above.
TransitionsRemoved();
for (PRUint32 i = 0, i_end = events.Length(); i < i_end; ++i) {
TransitionEventInfo &info = events[i];
nsEventDispatcher::Dispatch(info.mElement, mPresContext, &info.mEvent);
if (!mPresContext) {
break;
}
}
}
void
nsTransitionManager::TransitionsRemoved()
{
// If we have no transitions left, remove ourselves from the refresh
// driver.
if (PR_CLIST_IS_EMPTY(&mElementTransitions)) {
mPresContext->RefreshDriver()->RemoveRefreshObserver(this, Flush_Style);
}
}