Developer Documentation

- Main Page
- Related Pages
- Modules
- Namespaces
- Classes
- Files

- File List
- File Members

All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Properties Friends Macros Modules Pages
SpinBoxEventFilter.cc
1 /*===========================================================================*\
2 * *
3 * OpenFlipper *
4 * Copyright (c) 2001-2015, RWTH-Aachen University *
5 * Department of Computer Graphics and Multimedia *
6 * All rights reserved. *
7 * www.openflipper.org *
8 * *
9 *---------------------------------------------------------------------------*
10 * This file is part of OpenFlipper. *
11 *---------------------------------------------------------------------------*
12 * *
13 * Redistribution and use in source and binary forms, with or without *
14 * modification, are permitted provided that the following conditions *
15 * are met: *
16 * *
17 * 1. Redistributions of source code must retain the above copyright notice, *
18 * this list of conditions and the following disclaimer. *
19 * *
20 * 2. Redistributions in binary form must reproduce the above copyright *
21 * notice, this list of conditions and the following disclaimer in the *
22 * documentation and/or other materials provided with the distribution. *
23 * *
24 * 3. Neither the name of the copyright holder nor the names of its *
25 * contributors may be used to endorse or promote products derived from *
26 * this software without specific prior written permission. *
27 * *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS *
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED *
30 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
31 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER *
32 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, *
33 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, *
34 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR *
35 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF *
36 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING *
37 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS *
38 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *
39 * *
40 \*===========================================================================*/
41
42 /*===========================================================================*\
43 * *
44 * $Revision$ *
45 * $Author$ *
46 * $Date$ *
47 * *
48 \*===========================================================================*/
49
50 /*
51 * SpinBoxEventFilter.cc
52 *
53 * Created on: Aug 1, 2013
54 * Author: ebke
55 */
56
57 //#define VERBOSE_DEBUGGING_OUTPUT
58
59 #include "SpinBoxEventFilter.hh"
60
61 #include <QAbstractSpinBox>
62 #include <QEvent>
63 #include <QMetaEnum>
64 #include <stack>
65
66 #ifdef VERBOSE_DEBUGGING_OUTPUT
67 #include <iostream>
68 #endif
69
70 SpinBoxEventFilter::SpinBoxEventFilter(QObject *parent) :
71 QObject(parent), scrolling(false) {
72
73 scrollingTimer.setSingleShot(true);
74 scrollingTimer.setInterval(500);
75
76 connect(&scrollingTimer, SIGNAL( timeout() ), this, SLOT( unsetScrolling() ));
77 }
78
79 SpinBoxEventFilter::~SpinBoxEventFilter() {
80 }
81
82 bool SpinBoxEventFilter::eventFilter(QObject *object, QEvent *event) {
83
84 if (event->type() != QEvent::Wheel) return QObject::eventFilter(object, event);
85
86 QWidget *widget = qobject_cast<QWidget*>(object);
87
88 if (scrollAreas.find(widget) != scrollAreas.end()) {
89 #ifdef VERBOSE_DEBUGGING_OUTPUT
90 std::cout << "Reset isScrolling." << std::endl;
91 #endif
92 setScrolling();
93 return QObject::eventFilter(object, event);
94 }
95
96 if (!isScrolling() && widget->isEnabled()) {
97 #ifdef VERBOSE_DEBUGGING_OUTPUT
98 std::cout << "Not scrolling. Letting wheel event pass." << std::endl;
99 #endif
100 return QObject::eventFilter(object, event);
101 }
102
103 setScrolling();
104 event->ignore();
105 #ifdef VERBOSE_DEBUGGING_OUTPUT
106 std::cout << "Swallowing wheel event." << std::endl;
107 #endif
108 return true;
109
110 //#ifdef VERBOSE_DEBUGGING_OUTPUT
111 // std::cout << "Not a spin box. Letting wheel event pass." << std::endl;
112 //#endif
113 // return QObject::eventFilter(object, event);
114 }
115
116 inline bool SpinBoxEventFilter::isScrolling() {
117 return scrolling;
118 }
119
120 void SpinBoxEventFilter::hookUpToWidgetTree(QWidget *root_widget) {
121 std::stack<QWidget*> dfs;
122 dfs.push(root_widget);
123
124 while (!dfs.empty()) {
125 QWidget *cur = dfs.top(); dfs.pop();
126
127 cur->installEventFilter(this);
128
129 const QObjectList &children = cur->children();
130 for (QObjectList::const_iterator it = children.begin(), it_end = children.end();
131 it != it_end; ++it) {
132
133 QWidget *widget = qobject_cast<QWidget*>(*it);
134 if (widget)
135 dfs.push(widget);
136 }
137 }
138 }
139
140 void SpinBoxEventFilter::registerScrollArea(QWidget *scrollArea) {
141 scrollAreas.insert(scrollArea);
142 scrollArea->installEventFilter(this);
143 }
144
145 void SpinBoxEventFilter::setScrolling() {
146 scrolling = true;
147 scrollingTimer.start();
148 }
149
150 void SpinBoxEventFilter::unsetScrolling() {
151 #ifdef VERBOSE_DEBUGGING_OUTPUT
152 std::cout << "Scrolling timeout." << std::endl;
153 #endif
154 scrolling = false;
155 }