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50
51#include "window.h"
52
53#include <private/qguiapplication_p.h>
54
55#include <QBackingStore>
56#include <QPainter>
57
58static int colorIndexId = 0;
59
60QColor colorTable[] =
61{
62 QColor("#f09f8f"),
63 QColor("#a2bff2"),
64 QColor("#c0ef8f")
65};
66
67Window::Window(QScreen *screen)
68 : QWindow(screen)
69 , m_backgroundColorIndex(colorIndexId++)
70{
71 initialize();
72}
73
74Window::Window(QWindow *parent)
75 : QWindow(parent)
76 , m_backgroundColorIndex(colorIndexId++)
77{
78 initialize();
79}
80
81void Window::initialize()
82{
83 if (parent())
84 setGeometry(QRect(160, 120, 320, 240));
85 else {
86 setFlags(flags() | Qt::WindowTitleHint | Qt::WindowSystemMenuHint
87 | Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint);
88 const QSize baseSize = QSize(640, 480);
89 setGeometry(QRect(geometry().topLeft(), baseSize));
90
91 setSizeIncrement(QSize(10, 10));
92 setBaseSize(baseSize);
93 setMinimumSize(QSize(240, 160));
94 setMaximumSize(QSize(800, 600));
95 }
96
97 create();
98 m_backingStore = new QBackingStore(this);
99
100 m_image = QImage(geometry().size(), QImage::Format_RGB32);
101 m_image.fill(pixel: colorTable[m_backgroundColorIndex % (sizeof(colorTable) / sizeof(colorTable[0]))].rgba());
102
103 m_lastPos = QPoint(-1, -1);
104 m_renderTimer = 0;
105}
106
107void Window::mousePressEvent(QMouseEvent *event)
108{
109 m_lastPos = event->pos();
110}
111
112void Window::mouseMoveEvent(QMouseEvent *event)
113{
114 if (m_lastPos != QPoint(-1, -1)) {
115 QPainter p(&m_image);
116 p.setRenderHint(hint: QPainter::Antialiasing);
117 p.drawLine(p1: m_lastPos, p2: event->pos());
118 m_lastPos = event->pos();
119
120 scheduleRender();
121 }
122}
123
124void Window::mouseReleaseEvent(QMouseEvent *event)
125{
126 if (m_lastPos != QPoint(-1, -1)) {
127 QPainter p(&m_image);
128 p.setRenderHint(hint: QPainter::Antialiasing);
129 p.drawLine(p1: m_lastPos, p2: event->pos());
130 m_lastPos = QPoint(-1, -1);
131
132 scheduleRender();
133 }
134}
135
136void Window::exposeEvent(QExposeEvent *)
137{
138 scheduleRender();
139}
140
141void Window::resizeEvent(QResizeEvent *)
142{
143 QImage old = m_image;
144
145 int width = qMax(a: geometry().width(), b: old.width());
146 int height = qMax(a: geometry().height(), b: old.height());
147
148 if (width > old.width() || height > old.height()) {
149 m_image = QImage(width, height, QImage::Format_RGB32);
150 m_image.fill(pixel: colorTable[(m_backgroundColorIndex) % (sizeof(colorTable) / sizeof(colorTable[0]))].rgba());
151
152 QPainter p(&m_image);
153 p.drawImage(x: 0, y: 0, image: old);
154 }
155 scheduleRender();
156}
157
158void Window::keyPressEvent(QKeyEvent *event)
159{
160 switch (event->key()) {
161 case Qt::Key_Backspace:
162 m_text.chop(n: 1);
163 break;
164 case Qt::Key_Enter:
165 case Qt::Key_Return:
166 m_text.append(c: '\n');
167 break;
168 default:
169 m_text.append(s: event->text());
170 break;
171 }
172 scheduleRender();
173}
174
175void Window::scheduleRender()
176{
177 if (!m_renderTimer)
178 m_renderTimer = startTimer(interval: 1);
179}
180
181void Window::timerEvent(QTimerEvent *)
182{
183 if (isExposed())
184 render();
185 killTimer(id: m_renderTimer);
186 m_renderTimer = 0;
187}
188
189void Window::render()
190{
191 QRect rect(QPoint(), geometry().size());
192 m_backingStore->resize(size: rect.size());
193
194 m_backingStore->beginPaint(rect);
195
196 QPaintDevice *device = m_backingStore->paintDevice();
197
198 QPainter p(device);
199 p.drawImage(x: 0, y: 0, image: m_image);
200
201 QFont font;
202 font.setPixelSize(32);
203
204 p.setFont(font);
205 p.drawText(r: rect, flags: 0, text: m_text);
206
207 m_backingStore->endPaint();
208 m_backingStore->flush(region: rect);
209}
210
211
212

source code of qtbase/examples/qpa/windows/window.cpp