1 files changed, 85 insertions, 0 deletions
diff --git a/layout/base/nsIFrameTraversal.h b/layout/base/nsIFrameTraversal.h
new file mode 100644
index 0000000000..9b9b3a39a6
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+++ b/layout/base/nsIFrameTraversal.h
@@ -0,0 +1,85 @@
+/* -*- 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 NSIFRAMETRAVERSAL_H
+#define NSIFRAMETRAVERSAL_H
+
+#include "nsISupports.h"
+
+class nsIFrame;
+class nsPresContext;
+
+#define NS_IFRAMEENUMERATOR_IID                      \
+  {                                                  \
+    0x7c633f5d, 0x91eb, 0x494e, {                    \
+      0xa1, 0x40, 0x17, 0x46, 0x17, 0x4c, 0x23, 0xd3 \
+    }                                                \
+  }
+
+class nsIFrameEnumerator : public nsISupports {
+ public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_IFRAMEENUMERATOR_IID)
+
+  virtual void First() = 0;
+  virtual void Next() = 0;
+  virtual nsIFrame* CurrentItem() = 0;
+  virtual bool IsDone() = 0;
+
+  virtual void Last() = 0;
+  virtual void Prev() = 0;
+
+  inline nsIFrame* Traverse(bool aForward) {
+    if (aForward) {
+      Next();
+    } else {
+      Prev();
+    }
+    return CurrentItem();
+  };
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsIFrameEnumerator, NS_IFRAMEENUMERATOR_IID)
+
+enum nsIteratorType { eLeaf, ePreOrder, ePostOrder };
+
+// {d33fe76c-207c-4359-a315-8eb1eecf80e5}
+#define NS_IFRAMETRAVERSAL_IID                       \
+  {                                                  \
+    0xd33fe76c, 0x207c, 0x4359, {                    \
+      0xa3, 0x15, 0x8e, 0xb1, 0xee, 0xcf, 0x80, 0xe5 \
+    }                                                \
+  }
+
+class nsIFrameTraversal : public nsISupports {
+ public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_IFRAMETRAVERSAL_IID)
+
+  /**
+   * Create a frame iterator with the specified properties.
+   * @param aEnumerator [out] the created iterator
+   * @param aPresContext [in]
+   * @param aStart [in] the frame to start iterating from
+   * @param aType [in] the type of the iterator: leaf, pre-order, or post-order
+   * @param aVisual [in] whether the iterator should traverse frames in visual
+   *        bidi order
+   * @param aLockInScrollView [in] whether to stop iterating when exiting a
+   *        scroll view
+   * @param aFollowOOFs [in] whether the iterator should follow out-of-flows.
+   *        If true, when reaching a placeholder frame while going down will get
+   *        the real frame. Going back up will go on past the placeholder,
+   *        so the placeholders are logically part of the frame tree.
+   * @param aSkipPopupChecks [in] if false, then don't iterate into or out of a
+   *        popup frame. If true, skip any popup related checks.
+   */
+  NS_IMETHOD NewFrameTraversal(nsIFrameEnumerator** aEnumerator,
+                               nsPresContext* aPresContext, nsIFrame* aStart,
+                               int32_t aType, bool aVisual,
+                               bool aLockInScrollView, bool aFollowOOFs,
+                               bool aSkipPopupChecks) = 0;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsIFrameTraversal, NS_IFRAMETRAVERSAL_IID)
+
+#endif  // NSIFRAMETRAVERSAL_H