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-rw-r--r--dom/base/SelectionChangeEventDispatcher.h69
1 files changed, 69 insertions, 0 deletions
diff --git a/dom/base/SelectionChangeEventDispatcher.h b/dom/base/SelectionChangeEventDispatcher.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_SelectionChangeEventDispatcher_h
+#define mozilla_SelectionChangeEventDispatcher_h
+
+#include "mozilla/Attributes.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsTArray.h"
+#include "nsCOMPtr.h"
+#include "nsDirection.h"
+
+class nsINode;
+class nsRange;
+
+namespace mozilla {
+
+namespace dom {
+class Document;
+class Selection;
+} // namespace dom
+
+class SelectionChangeEventDispatcher final {
+ public:
+ // SelectionChangeEventDispatcher has to participate in cycle collection
+ // because it holds strong references to nsINodes in its mOldRanges array.
+ NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(
+ SelectionChangeEventDispatcher)
+ NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(SelectionChangeEventDispatcher)
+
+ MOZ_CAN_RUN_SCRIPT
+ void OnSelectionChange(dom::Document* aDocument, dom::Selection* aSelection,
+ int16_t aReason);
+
+ // This field is used to keep track of the ranges which were present in the
+ // selection when the selectionchange event was previously fired. This allows
+ // for the selectionchange event to only be fired when a selection is actually
+ // changed.
+ struct RawRangeData {
+ // These properties are not void*s to avoid the potential situation where
+ // the nsINode is freed, and a new nsINode is allocated with the same
+ // address, which could potentially break the comparison logic. In reality,
+ // this is extremely unlikely to occur (potentially impossible), but these
+ // nsCOMPtrs are safer. They are never dereferenced.
+ nsCOMPtr<nsINode> mStartContainer;
+ nsCOMPtr<nsINode> mEndContainer;
+
+ // XXX These are int32_ts on nsRange, but uint32_ts in the return value
+ // of GetStart_, so I use uint32_ts here. See bug 1194256.
+ uint32_t mStartOffset;
+ uint32_t mEndOffset;
+
+ explicit RawRangeData(const nsRange* aRange);
+ bool Equals(const nsRange* aRange);
+ };
+
+ private:
+ nsTArray<RawRangeData> mOldRanges;
+ nsDirection mOldDirection;
+
+ ~SelectionChangeEventDispatcher() = default;
+};
+
+} // namespace mozilla
+
+#endif // mozilla_SelectionChangeEventDispatcher_h