Unity 8
screengrabber.cpp
1 /*
2  * Copyright (C) 2014-2015 Canonical, Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 3.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program. If not, see <http://www.gnu.org/licenses/>.
15  */
16 
17 #include "screengrabber.h"
18 
19 #include <QDir>
20 #include <QDateTime>
21 #include <QStandardPaths>
22 #include <QTemporaryDir>
23 #include <QtGui/QImage>
24 #include <QtGui/QGuiApplication>
25 #include <QtQuick/QQuickWindow>
26 
27 #include <QDebug>
28 
29 QString saveScreenshot(const QImage &screenshot, const QString &filename, const QString &format, int quality)
30 {
31  if (screenshot.save(filename, format.toLatin1().data(), quality)) {
32  return filename;
33  } else {
34  qWarning() << "ScreenGrabber: failed to save snapshot!";
35  }
36  return QString();
37 }
38 
39 ScreenGrabber::ScreenGrabber(QObject *parent)
40  : QObject(parent)
41 {
42  QObject::connect(&m_watcher,
43  &QFutureWatcher<QString>::finished,
44  this,
45  &ScreenGrabber::onScreenshotSaved);
46 
47  QDir screenshotsDir;
48  if (qEnvironmentVariableIsSet("UNITY_TESTING")) {
49  QTemporaryDir tDir;
50  tDir.setAutoRemove(false);
51  screenshotsDir = tDir.path();
52  } else {
53  screenshotsDir = QStandardPaths::writableLocation(QStandardPaths::PicturesLocation);
54  }
55  screenshotsDir.mkpath(QStringLiteral("Screenshots"));
56  screenshotsDir.cd(QStringLiteral("Screenshots"));
57  if (screenshotsDir.exists()) {
58  fileNamePrefix = screenshotsDir.absolutePath();
59  fileNamePrefix.append("/screenshot");
60  } else {
61  qWarning() << "ScreenGrabber: failed to create directory at: " << screenshotsDir.absolutePath();
62  }
63 }
64 
65 void ScreenGrabber::captureAndSave(int angle)
66 {
67  if (fileNamePrefix.isEmpty())
68  {
69  qWarning() << "ScreenShotter: no directory to save screenshot";
70  return;
71  }
72 
73  const QWindowList windows = QGuiApplication::topLevelWindows();
74  if (windows.empty())
75  {
76  qWarning() << "ScreenShotter: no top level windows found!";
77  return;
78  }
79 
80  QQuickWindow *main_window = qobject_cast<QQuickWindow *>(windows[0]);
81  if (!main_window)
82  {
83  qWarning() << "ScreenShotter: can only take screenshots of QQuickWindows";
84  return;
85  }
86 
87  const QImage screenshot = main_window->grabWindow().transformed(QTransform().rotate(angle));
88  const QString filename = makeFileName();
89  qDebug() << "Saving screenshot to" << filename;
90  QFuture<QString> saveFuture(QtConcurrent::run(saveScreenshot, screenshot, filename, getFormat(), screenshotQuality));
91  m_watcher.setFuture(saveFuture);
92 }
93 
94 void ScreenGrabber::onScreenshotSaved()
95 {
96  const QString filename = m_watcher.future().result();
97  if (!filename.isEmpty()) {
98  Q_EMIT screenshotSaved(filename);
99  }
100 }
101 
102 QString ScreenGrabber::makeFileName() const
103 {
104  QString fileName(fileNamePrefix);
105  fileName.append(QDateTime::currentDateTime().toString(QStringLiteral("yyyyMMdd_hhmmsszzz")));
106  fileName.append(".");
107  fileName.append(getFormat());
108  return fileName;
109 }
110 
111 QString ScreenGrabber::getFormat() const
112 {
113  //TODO: This should be configurable (perhaps through gsettings?)
114  return QStringLiteral("png");
115 }