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33
34 #include "chasewidget.h"
35
36 #include <QtCore/QPoint>
37
38 #include <QtWidgets/QApplication>
39 #include <QtGui/QHideEvent>
40 #include <QtGui/QPainter>
41 #include <QtGui/QPaintEvent>
42 #include <QtGui/QShowEvent>
43
ChaseWidget(QWidget * parent,QPixmap pixmap,bool pixmapEnabled)44 ChaseWidget::ChaseWidget(QWidget *parent, QPixmap pixmap, bool pixmapEnabled)
45 : QWidget(parent)
46 , m_segment(0)
47 , m_delay(100)
48 , m_step(40)
49 , m_timerId(-1)
50 , m_animated(false)
51 , m_pixmap(pixmap)
52 , m_pixmapEnabled(pixmapEnabled)
53 {
54 }
55
setAnimated(bool value)56 void ChaseWidget::setAnimated(bool value)
57 {
58 if (m_animated == value)
59 return;
60 m_animated = value;
61 if (m_timerId != -1) {
62 killTimer(m_timerId);
63 m_timerId = -1;
64 }
65 if (m_animated) {
66 m_segment = 0;
67 m_timerId = startTimer(m_delay);
68 }
69 update();
70 }
71
paintEvent(QPaintEvent * event)72 void ChaseWidget::paintEvent(QPaintEvent *event)
73 {
74 Q_UNUSED(event);
75 QPainter p(this);
76 if (m_pixmapEnabled && !m_pixmap.isNull()) {
77 p.drawPixmap(0, 0, m_pixmap);
78 return;
79 }
80
81 const int extent = qMin(width() - 8, height() - 8);
82 const int displ = extent / 4;
83 const int ext = extent / 4 - 1;
84
85 p.setRenderHint(QPainter::Antialiasing, true);
86
87 if(m_animated)
88 p.setPen(Qt::gray);
89 else
90 p.setPen(QPen(palette().dark().color()));
91
92 p.translate(width() / 2, height() / 2); // center
93
94 for (int segment = 0; segment < segmentCount(); ++segment) {
95 p.rotate(QApplication::isRightToLeft() ? m_step : -m_step);
96 if(m_animated)
97 p.setBrush(colorForSegment(segment));
98 else
99 p.setBrush(palette().background());
100 p.drawEllipse(QRect(displ, -ext / 2, ext, ext));
101 }
102 }
103
sizeHint() const104 QSize ChaseWidget::sizeHint() const
105 {
106 return QSize(32, 32);
107 }
108
timerEvent(QTimerEvent * event)109 void ChaseWidget::timerEvent(QTimerEvent *event)
110 {
111 if (event->timerId() == m_timerId) {
112 ++m_segment;
113 update();
114 }
115 QWidget::timerEvent(event);
116 }
117
colorForSegment(int seg) const118 QColor ChaseWidget::colorForSegment(int seg) const
119 {
120 int index = ((seg + m_segment) % segmentCount());
121 int comp = qMax(0, 255 - (index * (255 / segmentCount())));
122 return QColor(comp, comp, comp, 255);
123 }
124
segmentCount() const125 int ChaseWidget::segmentCount() const
126 {
127 return 360 / m_step;
128 }
129
setPixmapEnabled(bool enable)130 void ChaseWidget::setPixmapEnabled(bool enable)
131 {
132 m_pixmapEnabled = enable;
133 }
134
135