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39
40#ifndef QQUICKPOSITIONERS_P_P_H
41#define QQUICKPOSITIONERS_P_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtQuick/private/qtquickglobal_p.h>
55
56QT_REQUIRE_CONFIG(quick_positioners);
57
58#include "qquickpositioners_p.h"
59#include "qquickimplicitsizeitem_p_p.h"
60
61#include <private/qlazilyallocated_p.h>
62
63#include <QtCore/qobject.h>
64#include <QtCore/qstring.h>
65#include <QtCore/qtimer.h>
66
67QT_BEGIN_NAMESPACE
68
69class QQuickItemViewTransitioner;
70
71class QQuickBasePositionerPrivate : public QQuickImplicitSizeItemPrivate, public QQuickItemChangeListener
72{
73 Q_DECLARE_PUBLIC(QQuickBasePositioner)
74
75public:
76 struct ExtraData {
77 ExtraData();
78
79 qreal padding;
80 qreal topPadding;
81 qreal leftPadding;
82 qreal rightPadding;
83 qreal bottomPadding;
84 bool explicitTopPadding : 1;
85 bool explicitLeftPadding : 1;
86 bool explicitRightPadding : 1;
87 bool explicitBottomPadding : 1;
88 };
89 QLazilyAllocated<ExtraData> extra;
90
91 QQuickBasePositionerPrivate()
92 : spacing(0), type(QQuickBasePositioner::None)
93 , transitioner(0), positioningDirty(false)
94 , doingPositioning(false), anchorConflict(false), layoutDirection(Qt::LeftToRight)
95
96 {
97 }
98
99 void init(QQuickBasePositioner::PositionerType at)
100 {
101 type = at;
102 }
103
104 qreal spacing;
105
106 QQuickBasePositioner::PositionerType type;
107 QQuickItemViewTransitioner *transitioner;
108
109 void watchChanges(QQuickItem *other);
110 void unwatchChanges(QQuickItem* other);
111 void setPositioningDirty() {
112 Q_Q(QQuickBasePositioner);
113 if (!positioningDirty) {
114 positioningDirty = true;
115 q->polish();
116 }
117 }
118
119 bool positioningDirty : 1;
120 bool doingPositioning : 1;
121 bool anchorConflict : 1;
122
123 Qt::LayoutDirection layoutDirection;
124
125 void mirrorChange() override {
126 effectiveLayoutDirectionChange();
127 }
128 bool isLeftToRight() const {
129 if (type == QQuickBasePositioner::Vertical)
130 return true;
131 else
132 return effectiveLayoutMirror ? layoutDirection == Qt::RightToLeft : layoutDirection == Qt::LeftToRight;
133 }
134
135 void itemSiblingOrderChanged(QQuickItem* other) override
136 {
137 Q_UNUSED(other);
138 setPositioningDirty();
139 }
140
141 void itemGeometryChanged(QQuickItem *, QQuickGeometryChange change, const QRectF &) override
142 {
143 if (change.sizeChange())
144 setPositioningDirty();
145 }
146
147 void itemVisibilityChanged(QQuickItem *) override
148 {
149 setPositioningDirty();
150 }
151
152 void itemDestroyed(QQuickItem *item) override
153 {
154 Q_Q(QQuickBasePositioner);
155 int index = q->positionedItems.find(v: QQuickBasePositioner::PositionedItem(item));
156 if (index >= 0)
157 q->removePositionedItem(items: &q->positionedItems, index);
158 }
159
160 static Qt::LayoutDirection getLayoutDirection(const QQuickBasePositioner *positioner)
161 {
162 return positioner->d_func()->layoutDirection;
163 }
164
165 static Qt::LayoutDirection getEffectiveLayoutDirection(const QQuickBasePositioner *positioner)
166 {
167 if (positioner->d_func()->effectiveLayoutMirror)
168 return positioner->d_func()->layoutDirection == Qt::RightToLeft ? Qt::LeftToRight : Qt::RightToLeft;
169 else
170 return positioner->d_func()->layoutDirection;
171 }
172
173 virtual void effectiveLayoutDirectionChange()
174 {
175 }
176
177 inline qreal padding() const { return extra.isAllocated() ? extra->padding : 0.0; }
178 void setTopPadding(qreal value, bool reset = false);
179 void setLeftPadding(qreal value, bool reset = false);
180 void setRightPadding(qreal value, bool reset = false);
181 void setBottomPadding(qreal value, bool reset = false);
182};
183
184QT_END_NAMESPACE
185
186#endif // QQUICKPOSITIONERS_P_P_H
187

source code of qtdeclarative/src/quick/items/qquickpositioners_p_p.h