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50
51#include "maskedmousearea.h"
52
53#include <QStyleHints>
54#include <QGuiApplication>
55#include <qqmlfile.h>
56
57MaskedMouseArea::MaskedMouseArea(QQuickItem *parent)
58 : QQuickItem(parent),
59 m_pressed(false),
60 m_alphaThreshold(0.0),
61 m_containsMouse(false)
62{
63 setAcceptHoverEvents(true);
64 setAcceptedMouseButtons(Qt::LeftButton);
65}
66
67void MaskedMouseArea::setPressed(bool pressed)
68{
69 if (m_pressed != pressed) {
70 m_pressed = pressed;
71 emit pressedChanged();
72 }
73}
74
75void MaskedMouseArea::setContainsMouse(bool containsMouse)
76{
77 if (m_containsMouse != containsMouse) {
78 m_containsMouse = containsMouse;
79 emit containsMouseChanged();
80 }
81}
82
83void MaskedMouseArea::setMaskSource(const QUrl &source)
84{
85 if (m_maskSource != source) {
86 m_maskSource = source;
87 m_maskImage = QImage(QQmlFile::urlToLocalFileOrQrc(source));
88 emit maskSourceChanged();
89 }
90}
91
92void MaskedMouseArea::setAlphaThreshold(qreal threshold)
93{
94 if (m_alphaThreshold != threshold) {
95 m_alphaThreshold = threshold;
96 emit alphaThresholdChanged();
97 }
98}
99
100bool MaskedMouseArea::contains(const QPointF &point) const
101{
102 if (!QQuickItem::contains(point) || m_maskImage.isNull())
103 return false;
104
105 QPoint p = point.toPoint();
106
107 if (p.x() < 0 || p.x() >= m_maskImage.width() ||
108 p.y() < 0 || p.y() >= m_maskImage.height())
109 return false;
110
111 qreal r = qBound<int>(min: 0, val: m_alphaThreshold * 255, max: 255);
112 return qAlpha(rgb: m_maskImage.pixel(pt: p)) > r;
113}
114
115void MaskedMouseArea::mousePressEvent(QMouseEvent *event)
116{
117 setPressed(true);
118 m_pressPoint = event->pos();
119 emit pressed();
120}
121
122void MaskedMouseArea::mouseReleaseEvent(QMouseEvent *event)
123{
124 setPressed(false);
125 emit released();
126
127 const int threshold = qApp->styleHints()->startDragDistance();
128 const bool isClick = (threshold >= qAbs(t: event->x() - m_pressPoint.x()) &&
129 threshold >= qAbs(t: event->y() - m_pressPoint.y()));
130
131 if (isClick)
132 emit clicked();
133}
134
135void MaskedMouseArea::mouseUngrabEvent()
136{
137 setPressed(false);
138 emit canceled();
139}
140
141void MaskedMouseArea::hoverEnterEvent(QHoverEvent *event)
142{
143 Q_UNUSED(event);
144 setContainsMouse(true);
145}
146
147void MaskedMouseArea::hoverLeaveEvent(QHoverEvent *event)
148{
149 Q_UNUSED(event);
150 setContainsMouse(false);
151}
152

source code of qtdeclarative/examples/quick/customitems/maskedmousearea/maskedmousearea.cpp