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3 ** Copyright (C) 2016 The Qt Company Ltd.
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6 ** This file is part of the documentation of the Qt Toolkit.
7 **
8 ** $QT_BEGIN_LICENSE:BSD$
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49 ****************************************************************************/
50
51 //! [0]
createApplication(int & argc,char * argv[])52 QCoreApplication* createApplication(int &argc, char *argv[])
53 {
54 for (int i = 1; i < argc; ++i)
55 if (!qstrcmp(argv[i], "-no-gui"))
56 return new QCoreApplication(argc, argv);
57 return new QApplication(argc, argv);
58 }
59
main(int argc,char * argv[])60 int main(int argc, char* argv[])
61 {
62 QScopedPointer<QCoreApplication> app(createApplication(argc, argv));
63
64 if (qobject_cast<QApplication *>(app.data())) {
65 // start GUI version...
66 } else {
67 // start non-GUI version...
68 }
69
70 return app->exec();
71 }
72 //! [0]
73
74
75 //! [1]
76 QApplication::setStyle(QStyleFactory::create("fusion"));
77 //! [1]
78
79
80 //! [2]
main(int argc,char * argv[])81 int main(int argc, char *argv[])
82 {
83 QApplication::setColorSpec(QApplication::ManyColor);
84 QApplication app(argc, argv);
85 ...
86 return app.exec();
87 }
88 //! [2]
89
90
91 //! [3]
sizeHint() const92 QSize MyWidget::sizeHint() const
93 {
94 return QSize(80, 25);
95 }
96 //! [3]
97
98
99 //! [4]
showAllHiddenTopLevelWidgets()100 void showAllHiddenTopLevelWidgets()
101 {
102 const auto topLevelWidgets = QApplication::topLevelWidgets();
103 for (QWidget *widget : topLevelWidgets) {
104 if (widget->isHidden())
105 widget->show();
106 }
107 }
108 //! [4]
109
110
111 //! [5]
updateAllWidgets()112 void updateAllWidgets()
113 {
114 const auto topLevelWidgets = QApplication::topLevelWidgets();
115 for (QWidget *widget : topLevelWidgets)
116 widget->update();
117 }
118 //! [5]
119
120
121 //! [6]
122 if ((startPos - currentPos).manhattanLength() >=
123 QApplication::startDragDistance())
124 startTheDrag();
125 //! [6]
126
127 //! [7]
128 QWidget *widget = qApp->widgetAt(x, y);
129 if (widget)
130 widget = widget->window();
131 //! [7]
132
133
134 //! [8]
135 QWidget *widget = qApp->widgetAt(point);
136 if (widget)
137 widget = widget->window();
138 //! [8]
139