1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/accessible/src/base/Relation.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,109 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set ts=2 et sw=2 tw=80: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef mozilla_a11y_relation_h_
1.11 +#define mozilla_a11y_relation_h_
1.12 +
1.13 +#include "AccIterator.h"
1.14 +
1.15 +#include "mozilla/Move.h"
1.16 +
1.17 +namespace mozilla {
1.18 +namespace a11y {
1.19 +
1.20 +/**
1.21 + * A collection of relation targets of a certain type. Targets are computed
1.22 + * lazily while enumerating.
1.23 + */
1.24 +class Relation
1.25 +{
1.26 +public:
1.27 + Relation() : mFirstIter(nullptr), mLastIter(nullptr) { }
1.28 +
1.29 + Relation(AccIterable* aIter) :
1.30 + mFirstIter(aIter), mLastIter(aIter) { }
1.31 +
1.32 + Relation(Accessible* aAcc) :
1.33 + mFirstIter(nullptr), mLastIter(nullptr)
1.34 + { AppendTarget(aAcc); }
1.35 +
1.36 + Relation(DocAccessible* aDocument, nsIContent* aContent) :
1.37 + mFirstIter(nullptr), mLastIter(nullptr)
1.38 + { AppendTarget(aDocument, aContent); }
1.39 +
1.40 + Relation(Relation&& aOther) :
1.41 + mFirstIter(Move(aOther.mFirstIter)), mLastIter(aOther.mLastIter)
1.42 + {
1.43 + aOther.mLastIter = nullptr;
1.44 + }
1.45 +
1.46 + Relation& operator = (Relation&& aRH)
1.47 + {
1.48 + mFirstIter = Move(aRH.mFirstIter);
1.49 + mLastIter = aRH.mLastIter;
1.50 + aRH.mLastIter = nullptr;
1.51 + return *this;
1.52 + }
1.53 +
1.54 + inline void AppendIter(AccIterable* aIter)
1.55 + {
1.56 + if (mLastIter)
1.57 + mLastIter->mNextIter = aIter;
1.58 + else
1.59 + mFirstIter = aIter;
1.60 +
1.61 + mLastIter = aIter;
1.62 + }
1.63 +
1.64 + /**
1.65 + * Append the given accessible to the set of related accessibles.
1.66 + */
1.67 + inline void AppendTarget(Accessible* aAcc)
1.68 + {
1.69 + if (aAcc)
1.70 + AppendIter(new SingleAccIterator(aAcc));
1.71 + }
1.72 +
1.73 + /**
1.74 + * Append the one accessible for this content node to the set of related
1.75 + * accessibles.
1.76 + */
1.77 + void AppendTarget(DocAccessible* aDocument, nsIContent* aContent)
1.78 + {
1.79 + if (aContent)
1.80 + AppendTarget(aDocument->GetAccessible(aContent));
1.81 + }
1.82 +
1.83 + /**
1.84 + * compute and return the next related accessible.
1.85 + */
1.86 + inline Accessible* Next()
1.87 + {
1.88 + Accessible* target = nullptr;
1.89 +
1.90 + // a trick nsAutoPtr deletes what it used to point to when assigned to
1.91 + while (mFirstIter && !(target = mFirstIter->Next()))
1.92 + mFirstIter = mFirstIter->mNextIter;
1.93 +
1.94 + if (!mFirstIter)
1.95 + mLastIter = nullptr;
1.96 +
1.97 + return target;
1.98 + }
1.99 +
1.100 +private:
1.101 + Relation& operator = (const Relation&) MOZ_DELETE;
1.102 + Relation(const Relation&) MOZ_DELETE;
1.103 +
1.104 + nsAutoPtr<AccIterable> mFirstIter;
1.105 + AccIterable* mLastIter;
1.106 +};
1.107 +
1.108 +} // namespace a11y
1.109 +} // namespace mozilla
1.110 +
1.111 +#endif
1.112 +
