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39
40#ifndef QLAYOUTENGINE_P_H
41#define QLAYOUTENGINE_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 "QtWidgets/qlayoutitem.h"
56#include "QtWidgets/qstyle.h"
57
58QT_BEGIN_NAMESPACE
59
60template <typename T> class QVector;
61
62struct QLayoutStruct
63{
64 inline void init(int stretchFactor = 0, int minSize = 0) {
65 stretch = stretchFactor;
66 minimumSize = sizeHint = minSize;
67 maximumSize = QLAYOUTSIZE_MAX;
68 expansive = false;
69 empty = true;
70 spacing = 0;
71 }
72
73 int smartSizeHint() {
74 return (stretch > 0) ? minimumSize : sizeHint;
75 }
76 int effectiveSpacer(int uniformSpacer) const {
77 Q_ASSERT(uniformSpacer >= 0 || spacing >= 0);
78 return (uniformSpacer >= 0) ? uniformSpacer : spacing;
79 }
80
81 // parameters
82 int stretch;
83 int sizeHint;
84 int maximumSize;
85 int minimumSize;
86 int spacing;
87 bool expansive;
88 bool empty;
89
90 // temporary storage
91 bool done;
92
93 // result
94 int pos;
95 int size;
96};
97
98
99Q_WIDGETS_EXPORT void qGeomCalc(QVector<QLayoutStruct> &chain, int start, int count,
100 int pos, int space, int spacer = -1);
101Q_WIDGETS_EXPORT QSize qSmartMinSize(const QSize &sizeHint, const QSize &minSizeHint,
102 const QSize &minSize, const QSize &maxSize,
103 const QSizePolicy &sizePolicy);
104Q_WIDGETS_EXPORT QSize qSmartMinSize(const QWidgetItem *i);
105Q_WIDGETS_EXPORT QSize qSmartMinSize(const QWidget *w);
106Q_WIDGETS_EXPORT QSize qSmartMaxSize(const QSize &sizeHint,
107 const QSize &minSize, const QSize &maxSize,
108 const QSizePolicy &sizePolicy, Qt::Alignment align = { });
109Q_WIDGETS_EXPORT QSize qSmartMaxSize(const QWidgetItem *i, Qt::Alignment align = { });
110Q_WIDGETS_EXPORT QSize qSmartMaxSize(const QWidget *w, Qt::Alignment align = { });
111
112Q_WIDGETS_EXPORT int qSmartSpacing(const QLayout *layout, QStyle::PixelMetric pm);
113
114/*
115 Modify total maximum (max), total expansion (exp), and total empty
116 when adding boxmax/boxexp.
117
118 Expansive boxes win over non-expansive boxes.
119 Non-empty boxes win over empty boxes.
120*/
121static inline void qMaxExpCalc(int & max, bool &exp, bool &empty,
122 int boxmax, bool boxexp, bool boxempty)
123{
124 if (exp) {
125 if (boxexp)
126 max = qMax(a: max, b: boxmax);
127 } else {
128 if (boxexp || (empty && (!boxempty || max == 0)))
129 max = boxmax;
130 else if (empty == boxempty)
131 max = qMin(a: max, b: boxmax);
132 }
133 exp = exp || boxexp;
134 empty = empty && boxempty;
135}
136
137QT_END_NAMESPACE
138
139#endif // QLAYOUTENGINE_P_H
140

source code of qtbase/src/widgets/kernel/qlayoutengine_p.h