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29
30#include "view.h"
31#include <QtGui/QResizeEvent>
32#include <QtWidgets/QGraphicsScene>
33#include <QtCharts/QChart>
34#include <QtCharts/QLineSeries>
35#include <QtCharts/QSplineSeries>
36#include <QtWidgets/QGraphicsTextItem>
37#include "callout.h"
38#include <QtGui/QMouseEvent>
39
40View::View(QWidget *parent)
41 : QGraphicsView(new QGraphicsScene, parent),
42 m_coordX(0),
43 m_coordY(0),
44 m_chart(0),
45 m_tooltip(0)
46{
47 setDragMode(QGraphicsView::NoDrag);
48 setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
49 setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
50
51 // chart
52 m_chart = new QChart;
53 m_chart->setMinimumSize(aw: 640, ah: 480);
54 m_chart->setTitle("Hover the line to show callout. Click the line to make it stay");
55 m_chart->legend()->hide();
56 QLineSeries *series = new QLineSeries;
57 series->append(x: 1, y: 3);
58 series->append(x: 4, y: 5);
59 series->append(x: 5, y: 4.5);
60 series->append(x: 7, y: 1);
61 series->append(x: 11, y: 2);
62 m_chart->addSeries(series);
63
64 QSplineSeries *series2 = new QSplineSeries;
65 series2->append(x: 1.6, y: 1.4);
66 series2->append(x: 2.4, y: 3.5);
67 series2->append(x: 3.7, y: 2.5);
68 series2->append(x: 7, y: 4);
69 series2->append(x: 10, y: 2);
70 m_chart->addSeries(series: series2);
71
72 m_chart->createDefaultAxes();
73 m_chart->setAcceptHoverEvents(true);
74
75 setRenderHint(hint: QPainter::Antialiasing);
76 scene()->addItem(item: m_chart);
77
78 m_coordX = new QGraphicsSimpleTextItem(m_chart);
79 m_coordX->setPos(ax: m_chart->size().width()/2 - 50, ay: m_chart->size().height());
80 m_coordX->setText("X: ");
81 m_coordY = new QGraphicsSimpleTextItem(m_chart);
82 m_coordY->setPos(ax: m_chart->size().width()/2 + 50, ay: m_chart->size().height());
83 m_coordY->setText("Y: ");
84
85 connect(sender: series, signal: &QLineSeries::clicked, receiver: this, slot: &View::keepCallout);
86 connect(sender: series, signal: &QLineSeries::hovered, receiver: this, slot: &View::tooltip);
87
88 connect(sender: series2, signal: &QSplineSeries::clicked, receiver: this, slot: &View::keepCallout);
89 connect(sender: series2, signal: &QSplineSeries::hovered, receiver: this, slot: &View::tooltip);
90
91 this->setMouseTracking(true);
92}
93
94void View::resizeEvent(QResizeEvent *event)
95{
96 if (scene()) {
97 scene()->setSceneRect(QRect(QPoint(0, 0), event->size()));
98 m_chart->resize(size: event->size());
99 m_coordX->setPos(ax: m_chart->size().width()/2 - 50, ay: m_chart->size().height() - 20);
100 m_coordY->setPos(ax: m_chart->size().width()/2 + 50, ay: m_chart->size().height() - 20);
101 const auto callouts = m_callouts;
102 for (Callout *callout : callouts)
103 callout->updateGeometry();
104 }
105 QGraphicsView::resizeEvent(event);
106}
107
108void View::mouseMoveEvent(QMouseEvent *event)
109{
110 m_coordX->setText(QString("X: %1").arg(a: m_chart->mapToValue(position: event->pos()).x()));
111 m_coordY->setText(QString("Y: %1").arg(a: m_chart->mapToValue(position: event->pos()).y()));
112 QGraphicsView::mouseMoveEvent(event);
113}
114
115void View::keepCallout()
116{
117 m_callouts.append(t: m_tooltip);
118 m_tooltip = new Callout(m_chart);
119}
120
121void View::tooltip(QPointF point, bool state)
122{
123 if (m_tooltip == 0)
124 m_tooltip = new Callout(m_chart);
125
126 if (state) {
127 m_tooltip->setText(QString("X: %1 \nY: %2 ").arg(a: point.x()).arg(a: point.y()));
128 m_tooltip->setAnchor(point);
129 m_tooltip->setZValue(11);
130 m_tooltip->updateGeometry();
131 m_tooltip->show();
132 } else {
133 m_tooltip->hide();
134 }
135}
136

source code of qtcharts/examples/charts/callout/view.cpp