1/****************************************************************************
2**
3** Copyright (C) 2017 The Qt Company Ltd.
4** Contact: https://www.qt.io/licensing/
5**
6** This file is part of the examples of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:BSD$
9** Commercial License Usage
10** Licensees holding valid commercial Qt licenses may use this file in
11** accordance with the commercial license agreement provided with the
12** Software or, alternatively, in accordance with the terms contained in
13** a written agreement between you and The Qt Company. For licensing terms
14** and conditions see https://www.qt.io/terms-conditions. For further
15** information use the contact form at https://www.qt.io/contact-us.
16**
17** BSD License Usage
18** Alternatively, you may use this file under the terms of the BSD license
19** as follows:
20**
21** "Redistribution and use in source and binary forms, with or without
22** modification, are permitted provided that the following conditions are
23** met:
24** * Redistributions of source code must retain the above copyright
25** notice, this list of conditions and the following disclaimer.
26** * Redistributions in binary form must reproduce the above copyright
27** notice, this list of conditions and the following disclaimer in
28** the documentation and/or other materials provided with the
29** distribution.
30** * Neither the name of The Qt Company Ltd nor the names of its
31** contributors may be used to endorse or promote products derived
32** from this software without specific prior written permission.
33**
34**
35** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
36** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
37** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
38** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
39** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
42** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
43** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
44** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
45** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
46**
47** $QT_END_LICENSE$
48**
49****************************************************************************/
50
51#include <QtWidgets>
52#include <QtSvg>
53#include "mimedata.h"
54#include "sourcewidget.h"
55
56SourceWidget::SourceWidget(QWidget *parent)
57 : QWidget(parent)
58{
59 QFile imageFile(":/images/example.svg");
60 imageFile.open(flags: QIODevice::ReadOnly);
61 imageData = imageFile.readAll();
62 imageFile.close();
63
64 QScrollArea *imageArea = new QScrollArea;
65 imageLabel = new QSvgWidget;
66 imageLabel->renderer()->load(contents: imageData);
67 imageArea->setWidget(imageLabel);
68 //imageLabel->setMinimumSize(imageLabel->renderer()->viewBox().size());
69
70 QLabel *instructTopLabel = new QLabel(tr(s: "This is an SVG drawing:"));
71 QLabel *instructBottomLabel = new QLabel(
72 tr(s: "Drag the icon to copy the drawing as a PNG file:"));
73 instructBottomLabel->setWordWrap(true);
74 QPushButton *dragIcon = new QPushButton(tr(s: "Export"));
75 dragIcon->setIcon(QIcon(":/images/drag.png"));
76
77 connect(sender: dragIcon, SIGNAL(pressed()), receiver: this, SLOT(startDrag()));
78
79 QGridLayout *layout = new QGridLayout;
80 layout->addWidget(instructTopLabel, row: 0, column: 0, rowSpan: 1, columnSpan: 2);
81 layout->addWidget(imageArea, row: 1, column: 0, rowSpan: 2, columnSpan: 2);
82 layout->addWidget(instructBottomLabel, row: 3, column: 0);
83 layout->addWidget(dragIcon, row: 3, column: 1);
84 setLayout(layout);
85 setWindowTitle(tr(s: "Delayed Encoding"));
86}
87
88//![1]
89void SourceWidget::createData(const QString &mimeType)
90{
91 if (mimeType != "image/png")
92 return;
93
94 QImage image(imageLabel->size(), QImage::Format_RGB32);
95 QPainter painter;
96 painter.begin(&image);
97 imageLabel->renderer()->render(p: &painter);
98 painter.end();
99
100 QByteArray data;
101 QBuffer buffer(&data);
102 buffer.open(openMode: QIODevice::WriteOnly);
103 image.save(device: &buffer, format: "PNG");
104 buffer.close();
105
106 mimeData->setData(mimetype: "image/png", data);
107}
108//![1]
109
110//![0]
111void SourceWidget::startDrag()
112{
113 mimeData = new MimeData;
114
115 connect(sender: mimeData, SIGNAL(dataRequested(QString)),
116 receiver: this, SLOT(createData(QString)), Qt::DirectConnection);
117
118 QDrag *drag = new QDrag(this);
119 drag->setMimeData(mimeData);
120 drag->setPixmap(QPixmap(":/images/drag.png"));
121
122 drag->exec(supportedActions: Qt::CopyAction);
123}
124//![0]
125
126

Provided by KDAB

Privacy Policy
Learn to use CMake with our Intro Training
Find out more

source code of qtsvg/examples/svg/draganddrop/delayedencoding/sourcewidget.cpp