gecko-dev/editor/libeditor/PlaceholderTransaction.cpp

275 строки
8.3 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "PlaceholderTransaction.h"
#include "CompositionTransaction.h"
#include "mozilla/EditorBase.h"
#include "mozilla/dom/Selection.h"
#include "nsGkAtoms.h"
#include "nsQueryObject.h"
namespace mozilla {
using namespace dom;
PlaceholderTransaction::PlaceholderTransaction()
: mAbsorb(true)
, mForwarding(nullptr)
, mCompositionTransaction(nullptr)
, mCommitted(false)
, mEditorBase(nullptr)
{
}
PlaceholderTransaction::~PlaceholderTransaction()
{
}
NS_IMPL_CYCLE_COLLECTION_CLASS(PlaceholderTransaction)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(PlaceholderTransaction,
EditAggregateTransaction)
if (tmp->mStartSel) {
ImplCycleCollectionUnlink(*tmp->mStartSel);
}
NS_IMPL_CYCLE_COLLECTION_UNLINK(mEndSel);
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(PlaceholderTransaction,
EditAggregateTransaction)
if (tmp->mStartSel) {
ImplCycleCollectionTraverse(cb, *tmp->mStartSel, "mStartSel", 0);
}
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEndSel);
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PlaceholderTransaction)
NS_INTERFACE_MAP_ENTRY(nsIAbsorbingTransaction)
NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
NS_INTERFACE_MAP_END_INHERITING(EditAggregateTransaction)
NS_IMPL_ADDREF_INHERITED(PlaceholderTransaction, EditAggregateTransaction)
NS_IMPL_RELEASE_INHERITED(PlaceholderTransaction, EditAggregateTransaction)
NS_IMETHODIMP
PlaceholderTransaction::Init(nsIAtom* aName,
SelectionState* aSelState,
EditorBase* aEditorBase)
{
NS_ENSURE_TRUE(aEditorBase && aSelState, NS_ERROR_NULL_POINTER);
mName = aName;
mStartSel = aSelState;
mEditorBase = aEditorBase;
return NS_OK;
}
NS_IMETHODIMP
PlaceholderTransaction::DoTransaction()
{
return NS_OK;
}
NS_IMETHODIMP
PlaceholderTransaction::UndoTransaction()
{
// Undo transactions.
nsresult rv = EditAggregateTransaction::UndoTransaction();
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(mStartSel, NS_ERROR_NULL_POINTER);
// now restore selection
RefPtr<Selection> selection = mEditorBase->GetSelection();
NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
return mStartSel->RestoreSelection(selection);
}
NS_IMETHODIMP
PlaceholderTransaction::RedoTransaction()
{
// Redo transactions.
nsresult rv = EditAggregateTransaction::RedoTransaction();
NS_ENSURE_SUCCESS(rv, rv);
// now restore selection
RefPtr<Selection> selection = mEditorBase->GetSelection();
NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
return mEndSel.RestoreSelection(selection);
}
NS_IMETHODIMP
PlaceholderTransaction::Merge(nsITransaction* aTransaction,
bool* aDidMerge)
{
NS_ENSURE_TRUE(aDidMerge && aTransaction, NS_ERROR_NULL_POINTER);
// set out param default value
*aDidMerge=false;
if (mForwarding)
{
NS_NOTREACHED("tried to merge into a placeholder that was in forwarding mode!");
return NS_ERROR_FAILURE;
}
// check to see if aTransaction is one of the editor's
// private transactions. If not, we want to avoid merging
// the foreign transaction into our placeholder since we
// don't know what it does.
nsCOMPtr<nsPIEditorTransaction> pTxn = do_QueryInterface(aTransaction);
NS_ENSURE_TRUE(pTxn, NS_OK); // it's foreign so just bail!
// XXX: hack, not safe! need nsIEditTransaction!
EditTransactionBase* editTransactionBase = (EditTransactionBase*)aTransaction;
// determine if this incoming txn is a placeholder txn
nsCOMPtr<nsIAbsorbingTransaction> absorbingTransaction =
do_QueryObject(editTransactionBase);
// We are absorbing all transactions if mAbsorb is lit.
if (mAbsorb) {
RefPtr<CompositionTransaction> otherTransaction =
do_QueryObject(aTransaction);
if (otherTransaction) {
// special handling for CompositionTransaction's: they need to merge with
// any previous CompositionTransaction in this placeholder, if possible.
if (!mCompositionTransaction) {
// this is the first IME txn in the placeholder
mCompositionTransaction = otherTransaction;
AppendChild(editTransactionBase);
} else {
bool didMerge;
mCompositionTransaction->Merge(otherTransaction, &didMerge);
if (!didMerge) {
// it wouldn't merge. Earlier IME txn is already committed and will
// not absorb further IME txns. So just stack this one after it
// and remember it as a candidate for further merges.
mCompositionTransaction = otherTransaction;
AppendChild(editTransactionBase);
}
}
} else if (!absorbingTransaction) {
// See bug 171243: just drop incoming placeholders on the floor.
// Their children will be swallowed by this preexisting one.
AppendChild(editTransactionBase);
}
*aDidMerge = true;
// RememberEndingSelection();
// efficiency hack: no need to remember selection here, as we haven't yet
// finished the initial batch and we know we will be told when the batch ends.
// we can remeber the selection then.
} else {
// merge typing or IME or deletion transactions if the selection matches
if (((mName.get() == nsGkAtoms::TypingTxnName) ||
(mName.get() == nsGkAtoms::IMETxnName) ||
(mName.get() == nsGkAtoms::DeleteTxnName))
&& !mCommitted) {
if (absorbingTransaction) {
nsCOMPtr<nsIAtom> atom;
absorbingTransaction->GetTxnName(getter_AddRefs(atom));
if (atom && atom == mName) {
// check if start selection of next placeholder matches
// end selection of this placeholder
bool isSame;
absorbingTransaction->StartSelectionEquals(&mEndSel, &isSame);
if (isSame) {
mAbsorb = true; // we need to start absorbing again
absorbingTransaction->ForwardEndBatchTo(this);
// AppendChild(editTransactionBase);
// see bug 171243: we don't need to merge placeholders
// into placeholders. We just reactivate merging in the pre-existing
// placeholder and drop the new one on the floor. The EndPlaceHolderBatch()
// call on the new placeholder will be forwarded to this older one.
RememberEndingSelection();
*aDidMerge = true;
}
}
}
}
}
return NS_OK;
}
NS_IMETHODIMP
PlaceholderTransaction::GetTxnDescription(nsAString& aString)
{
aString.AssignLiteral("PlaceholderTransaction: ");
if (mName)
{
nsAutoString name;
mName->ToString(name);
aString += name;
}
return NS_OK;
}
NS_IMETHODIMP
PlaceholderTransaction::GetTxnName(nsIAtom** aName)
{
return GetName(aName);
}
NS_IMETHODIMP
PlaceholderTransaction::StartSelectionEquals(SelectionState* aSelState,
bool* aResult)
{
// determine if starting selection matches the given selection state.
// note that we only care about collapsed selections.
NS_ENSURE_TRUE(aResult && aSelState, NS_ERROR_NULL_POINTER);
if (!mStartSel->IsCollapsed() || !aSelState->IsCollapsed())
{
*aResult = false;
return NS_OK;
}
*aResult = mStartSel->IsEqual(aSelState);
return NS_OK;
}
NS_IMETHODIMP
PlaceholderTransaction::EndPlaceHolderBatch()
{
mAbsorb = false;
if (mForwarding)
{
nsCOMPtr<nsIAbsorbingTransaction> plcTxn = do_QueryReferent(mForwarding);
if (plcTxn) plcTxn->EndPlaceHolderBatch();
}
// remember our selection state.
return RememberEndingSelection();
}
NS_IMETHODIMP
PlaceholderTransaction::ForwardEndBatchTo(
nsIAbsorbingTransaction* aForwardingAddress)
{
mForwarding = do_GetWeakReference(aForwardingAddress);
return NS_OK;
}
NS_IMETHODIMP
PlaceholderTransaction::Commit()
{
mCommitted = true;
return NS_OK;
}
nsresult
PlaceholderTransaction::RememberEndingSelection()
{
RefPtr<Selection> selection = mEditorBase->GetSelection();
NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
mEndSel.SaveSelection(selection);
return NS_OK;
}
} // namespace mozilla