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50 
51 //! [0]
52 QGraphicsScene scene;
53 scene.addText("Hello, world!");
54 
55 QGraphicsView view(&scene);
56 view.show();
57 //! [0]
58 
59 
60 //! [1]
61 QGraphicsScene scene;
62 scene.addRect(QRectF(-10, -10, 20, 20));
63 
64 QGraphicsView view(&scene);
65 view.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
66 view.show();
67 //! [1]
68 
69 
70 //! [2]
71 QGraphicsView view;
72 view.setBackgroundBrush(QImage(":/images/backgroundtile.png"));
73 view.setCacheMode(QGraphicsView::CacheBackground);
74 //! [2]
75 
76 
77 //! [3]
78 QGraphicsScene scene;
79 scene.addText("GraphicsView rotated clockwise");
80 
81 QGraphicsView view(&scene);
82 view.rotate(90); // the text is rendered with a 90 degree clockwise rotation
83 view.show();
84 //! [3]
85 
86 
87 //! [4]
88 QGraphicsScene scene;
89 scene.addItem(...
90 ...
91 
92 QGraphicsView view(&scene);
93 view.show();
94 ...
95 
96 QPrinter printer(QPrinter::HighResolution);
97 printer.setPageSize(QPrinter::A4);
98 QPainter painter(&printer);
99 
100 // print, fitting the viewport contents into a full page
101 view.render(&painter);
102 
103 // print the upper half of the viewport into the lower.
104 // half of the page.
105 QRect viewport = view.viewport()->rect();
106 view.render(&painter,
107             QRectF(0, printer.height() / 2,
108                    printer.width(), printer.height() / 2),
109             viewport.adjusted(0, 0, 0, -viewport.height() / 2));
110 
111 //! [4]
112 
113 
114 //! [5]
115 void CustomView::mousePressEvent(QMouseEvent *event)
116 {
117     qDebug() << "There are" << items(event->pos()).size()
118              << "items at position" << mapToScene(event->pos());
119 }
120 //! [5]
121 
122 
123 //! [6]
124 void CustomView::mousePressEvent(QMouseEvent *event)
125 {
126     if (QGraphicsItem *item = itemAt(event->pos())) {
127         qDebug() << "You clicked on item" << item;
128     } else {
129         qDebug("You didn't click on an item.");
130     }
131 }
132 //! [6]
133 
134 
135 //! [7]
136 QGraphicsScene scene;
137 scene.addText("GraphicsView rotated clockwise");
138 
139 QGraphicsView view(&scene);
140 view.rotate(90); // the text is rendered with a 90 degree clockwise rotation
141 view.show();
142 //! [7]
143