| 1 |
/* This file is part of the KDE project. |
| 2 |
|
| 3 |
Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). |
| 4 |
|
| 5 |
This library is free software: you can redistribute it and/or modify |
| 6 |
it under the terms of the GNU Lesser General Public License as published by |
| 7 |
the Free Software Foundation, either version 2.1 or 3 of the License. |
| 8 |
|
| 9 |
This library is distributed in the hope that it will be useful, |
| 10 |
but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 |
GNU Lesser General Public License for more details. |
| 13 |
|
| 14 |
You should have received a copy of the GNU Lesser General Public License |
| 15 |
along with this library. If not, see <http://www.gnu.org/licenses/>. |
| 16 |
|
| 17 |
*/ |
| 18 |
|
| 19 |
#ifndef OBJECTTREE_H |
| 20 |
#define OBJECTTREE_H |
| 21 |
|
| 22 |
#include <QObject> |
| 23 |
#include <QStack> |
| 24 |
|
| 25 |
QT_BEGIN_NAMESPACE |
| 26 |
|
| 27 |
namespace ObjectTree |
| 28 |
{ |
| 29 |
|
| 30 |
/** |
| 31 |
* Depth-first iterator for QObject tree |
| 32 |
*/ |
| 33 |
class DepthFirstConstIterator |
| 34 |
{ |
| 35 |
public: |
| 36 |
DepthFirstConstIterator(); |
| 37 |
DepthFirstConstIterator(const QObject& root); |
| 38 |
|
| 39 |
DepthFirstConstIterator& operator++(); |
| 40 |
|
| 41 |
inline bool operator==(const DepthFirstConstIterator& other) const |
| 42 |
{ return other.m_pointee == m_pointee; } |
| 43 |
|
| 44 |
inline bool operator!=(const DepthFirstConstIterator& other) const |
| 45 |
{ return other.m_pointee != m_pointee; } |
| 46 |
|
| 47 |
inline const QObject* operator->() const { return m_pointee; } |
| 48 |
inline const QObject& operator*() const { return *m_pointee; } |
| 49 |
|
| 50 |
private: |
| 51 |
void backtrack(); |
| 52 |
|
| 53 |
private: |
| 54 |
const QObject* m_pointee; |
| 55 |
QStack<int> m_history; |
| 56 |
}; |
| 57 |
|
| 58 |
/** |
| 59 |
* Ancestor iterator for QObject tree |
| 60 |
*/ |
| 61 |
class AncestorConstIterator |
| 62 |
{ |
| 63 |
public: |
| 64 |
AncestorConstIterator(); |
| 65 |
AncestorConstIterator(const QObject& root); |
| 66 |
|
| 67 |
inline AncestorConstIterator& operator++() |
| 68 |
{ m_ancestors.pop(); return *this; } |
| 69 |
|
| 70 |
inline bool operator==(const AncestorConstIterator& other) const |
| 71 |
{ return other.m_ancestors == m_ancestors; } |
| 72 |
|
| 73 |
inline bool operator!=(const AncestorConstIterator& other) const |
| 74 |
{ return other.m_ancestors != m_ancestors; } |
| 75 |
|
| 76 |
inline const QObject* operator->() const { return m_ancestors.top(); } |
| 77 |
inline const QObject& operator*() const { return *m_ancestors.top(); } |
| 78 |
|
| 79 |
private: |
| 80 |
QStack<const QObject*> m_ancestors; |
| 81 |
|
| 82 |
}; |
| 83 |
|
| 84 |
/** |
| 85 |
* Generic algorithm for visiting nodes in an object tree. Nodes in the |
| 86 |
* tree are visited in a const context, therefore they are not modified |
| 87 |
* by this algorithm. |
| 88 |
* |
| 89 |
* Visitor must provide functions with the following signatures: |
| 90 |
* |
| 91 |
* Called before visit begins |
| 92 |
* void visitPrepare() |
| 93 |
* |
| 94 |
* Called on each node visited |
| 95 |
* void visitNode(const QObject& object) |
| 96 |
* |
| 97 |
* Called when visit is complete |
| 98 |
* void visitComplete() |
| 99 |
*/ |
| 100 |
template <class Iterator, class Visitor> |
| 101 |
void visit(Iterator begin, Iterator end, Visitor& visitor) |
| 102 |
{ |
| 103 |
visitor.visitPrepare(); |
| 104 |
|
| 105 |
for ( ; begin != end; ++begin) |
| 106 |
visitor.visitNode(*begin); |
| 107 |
|
| 108 |
visitor.visitComplete(); |
| 109 |
} |
| 110 |
|
| 111 |
} // namespace ObjectTree |
| 112 |
|
| 113 |
QT_END_NAMESPACE |
| 114 |
|
| 115 |
#endif // OBJECTTREE_H |
