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39
40#ifndef QABSTRACTSCROLLAREA_P_H
41#define QABSTRACTSCROLLAREA_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 <QtWidgets/private/qtwidgetsglobal_p.h>
55#include "private/qframe_p.h"
56#include "qabstractscrollarea.h"
57
58QT_BEGIN_NAMESPACE
59
60#if QT_CONFIG(scrollarea)
61
62class QScrollBar;
63class QAbstractScrollAreaScrollBarContainer;
64
65// ### Qt 6: is the export still needed? If not, unexport QFramePrivate, too.
66class Q_WIDGETS_EXPORT QAbstractScrollAreaPrivate: public QFramePrivate
67{
68 Q_DECLARE_PUBLIC(QAbstractScrollArea)
69
70public:
71 QAbstractScrollAreaPrivate();
72 ~QAbstractScrollAreaPrivate();
73
74 void replaceScrollBar(QScrollBar *scrollBar, Qt::Orientation orientation);
75
76 QAbstractScrollAreaScrollBarContainer *scrollBarContainers[Qt::Vertical + 1];
77 QScrollBar *hbar, *vbar;
78 Qt::ScrollBarPolicy vbarpolicy, hbarpolicy;
79
80 bool shownOnce;
81 bool inResize;
82 mutable QSize sizeHint;
83 QAbstractScrollArea::SizeAdjustPolicy sizeAdjustPolicy;
84
85 QWidget *viewport;
86 QWidget *cornerWidget;
87 QRect cornerPaintingRect;
88
89 int left, top, right, bottom; // viewport margin
90
91 int xoffset, yoffset;
92 QPoint overshoot;
93
94 void init();
95 void layoutChildren();
96 void layoutChildren_helper(bool *needHorizontalScrollbar, bool *needVerticalScrollbar);
97 // ### Fix for 4.4, talk to Bjoern E or Girish.
98 virtual void scrollBarPolicyChanged(Qt::Orientation, Qt::ScrollBarPolicy) {}
99 bool canStartScrollingAt( const QPoint &startPos );
100
101 void flashScrollBars();
102 void setScrollBarTransient(QScrollBar *scrollBar, bool transient);
103
104 void _q_hslide(int);
105 void _q_vslide(int);
106 void _q_showOrHideScrollBars();
107
108 virtual QPoint contentsOffset() const;
109
110 inline bool viewportEvent(QEvent *event)
111 { return q_func()->viewportEvent(event); }
112 QScopedPointer<QObject> viewportFilter;
113};
114
115class QAbstractScrollAreaFilter : public QObject
116{
117 Q_OBJECT
118public:
119 QAbstractScrollAreaFilter(QAbstractScrollAreaPrivate *p) : d(p)
120 { setObjectName(QLatin1String("qt_abstractscrollarea_filter")); }
121 bool eventFilter(QObject *o, QEvent *e) override
122 { return (o == d->viewport ? d->viewportEvent(event: e) : false); }
123private:
124 QAbstractScrollAreaPrivate *d;
125};
126
127class QBoxLayout;
128class QAbstractScrollAreaScrollBarContainer : public QWidget
129{
130public:
131 enum LogicalPosition { LogicalLeft = 1, LogicalRight = 2 };
132
133 QAbstractScrollAreaScrollBarContainer(Qt::Orientation orientation, QWidget *parent);
134 void addWidget(QWidget *widget, LogicalPosition position);
135 QWidgetList widgets(LogicalPosition position);
136 void removeWidget(QWidget *widget);
137
138 QScrollBar *scrollBar;
139 QBoxLayout *layout;
140private:
141 int scrollBarLayoutIndex() const;
142
143 Qt::Orientation orientation;
144};
145
146#endif // QT_CONFIG(scrollarea)
147
148QT_END_NAMESPACE
149
150#endif // QABSTRACTSCROLLAREA_P_H
151

source code of qtbase/src/widgets/widgets/qabstractscrollarea_p.h