1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
|
/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the test suite of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
#include "mousepangesturerecognizer.h"
class ScrollArea : public QScrollArea
{
Q_OBJECT
public:
ScrollArea(QWidget *parent = 0)
: QScrollArea(parent), outside(false)
{
viewport()->grabGesture(Qt::PanGesture, Qt::ReceivePartialGestures);
}
protected:
bool viewportEvent(QEvent *event)
{
if (event->type() == QEvent::Gesture) {
gestureEvent(static_cast<QGestureEvent *>(event));
return true;
} else if (event->type() == QEvent::GestureOverride) {
QGestureEvent *ge = static_cast<QGestureEvent *>(event);
if (QPanGesture *pan = static_cast<QPanGesture *>(ge->gesture(Qt::PanGesture)))
if (pan->state() == Qt::GestureStarted) {
outside = false;
}
}
return QScrollArea::viewportEvent(event);
}
void gestureEvent(QGestureEvent *event)
{
QPanGesture *pan = static_cast<QPanGesture *>(event->gesture(Qt::PanGesture));
if (pan) {
switch(pan->state()) {
case Qt::GestureStarted: qDebug() << this << "Pan: started"; break;
case Qt::GestureFinished: qDebug() << this << "Pan: finished"; break;
case Qt::GestureCanceled: qDebug() << this << "Pan: canceled"; break;
case Qt::GestureUpdated: break;
default: qDebug() << this << "Pan: <unknown state>"; break;
}
if (pan->state() == Qt::GestureStarted)
outside = false;
event->ignore();
event->ignore(pan);
if (outside)
return;
const QPointF delta = pan->delta();
const QPointF totalOffset = pan->offset();
QScrollBar *vbar = verticalScrollBar();
QScrollBar *hbar = horizontalScrollBar();
if ((vbar->value() == vbar->minimum() && totalOffset.y() > 10) ||
(vbar->value() == vbar->maximum() && totalOffset.y() < -10)) {
outside = true;
return;
}
if ((hbar->value() == hbar->minimum() && totalOffset.x() > 10) ||
(hbar->value() == hbar->maximum() && totalOffset.x() < -10)) {
outside = true;
return;
}
vbar->setValue(vbar->value() - delta.y());
hbar->setValue(hbar->value() - delta.x());
event->accept(pan);
}
}
private:
bool outside;
};
class Slider : public QSlider
{
public:
Slider(Qt::Orientation orientation, QWidget *parent = 0)
: QSlider(orientation, parent)
{
grabGesture(Qt::PanGesture);
}
protected:
bool event(QEvent *event)
{
if (event->type() == QEvent::Gesture) {
gestureEvent(static_cast<QGestureEvent *>(event));
return true;
}
return QSlider::event(event);
}
void gestureEvent(QGestureEvent *event)
{
QPanGesture *pan = static_cast<QPanGesture *>(event->gesture(Qt::PanGesture));
if (pan) {
switch (pan->state()) {
case Qt::GestureStarted: qDebug() << this << "Pan: started"; break;
case Qt::GestureFinished: qDebug() << this << "Pan: finished"; break;
case Qt::GestureCanceled: qDebug() << this << "Pan: canceled"; break;
case Qt::GestureUpdated: break;
default: qDebug() << this << "Pan: <unknown state>"; break;
}
if (pan->state() == Qt::GestureStarted)
outside = false;
event->ignore();
event->ignore(pan);
if (outside)
return;
const QPointF delta = pan->delta();
const QPointF totalOffset = pan->offset();
if (orientation() == Qt::Horizontal) {
if ((value() == minimum() && totalOffset.x() < -10) ||
(value() == maximum() && totalOffset.x() > 10)) {
outside = true;
return;
}
if (totalOffset.y() < 40 && totalOffset.y() > -40) {
setValue(value() + delta.x());
event->accept(pan);
} else {
outside = true;
}
} else if (orientation() == Qt::Vertical) {
if ((value() == maximum() && totalOffset.y() < -10) ||
(value() == minimum() && totalOffset.y() > 10)) {
outside = true;
return;
}
if (totalOffset.x() < 40 && totalOffset.x() > -40) {
setValue(value() - delta.y());
event->accept(pan);
} else {
outside = true;
}
}
}
}
private:
bool outside;
};
class MainWindow : public QMainWindow
{
public:
MainWindow()
{
rootScrollArea = new ScrollArea;
rootScrollArea->setObjectName(QLatin1String("rootScrollArea"));
setCentralWidget(rootScrollArea);
QWidget *root = new QWidget;
root->setFixedSize(3000, 3000);
rootScrollArea->setWidget(root);
Slider *verticalSlider = new Slider(Qt::Vertical, root);
verticalSlider->setObjectName(QLatin1String("verticalSlider"));
verticalSlider ->move(650, 1100);
Slider *horizontalSlider = new Slider(Qt::Horizontal, root);
horizontalSlider->setObjectName(QLatin1String("horizontalSlider"));
horizontalSlider ->move(600, 1000);
childScrollArea = new ScrollArea(root);
childScrollArea->setObjectName(QLatin1String("childScrollArea"));
childScrollArea->move(500, 500);
QWidget *w = new QWidget;
w->setMinimumWidth(700);
QVBoxLayout *l = new QVBoxLayout(w);
l->setMargin(20);
for (int i = 0; i < 100; ++i) {
QWidget *w = new QWidget;
QHBoxLayout *ll = new QHBoxLayout(w);
ll->addWidget(new QLabel(QString("Label %1").arg(i)));
ll->addWidget(new QPushButton(QString("Button %1").arg(i)));
l->addWidget(w);
}
childScrollArea->setWidget(w);
#if defined(Q_OS_WIN)
// Windows can force Qt to create a native window handle for an
// intermediate widget and that will block gesture to get touch events.
// So this hack to make sure gestures get all touch events they need.
foreach (QObject *w, children())
if (w->isWidgetType())
static_cast<QWidget *>(w)->setAttribute(Qt::WA_AcceptTouchEvents);
#endif
}
private:
ScrollArea *rootScrollArea;
ScrollArea *childScrollArea;
};
int main(int argc, char **argv)
{
QApplication app(argc, argv);
QGestureRecognizer::registerRecognizer(new MousePanGestureRecognizer);
MainWindow w;
w.show();
return app.exec();
}
#include "main.moc"
|
