pv/widgets/popup.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2013 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <algorithm>
  21 #include <cassert>
  22
  23 #include <QApplication>
  24 #include <QDesktopWidget>
  25 #include <QLineEdit>
  26 #include <QtGui>
  27
  28 #include "popup.hpp"
  29
  30 using std::max;
  31 using std::min;
  32
  33 namespace pv {
  34 namespace widgets {
  35
  36 const unsigned int Popup::ArrowLength = 10;
  37 const unsigned int Popup::ArrowOverlap = 3;
  38 const unsigned int Popup::MarginWidth = 6;
  39
  40 Popup::Popup(QWidget *parent) :
  41         QWidget(parent, Qt::Popup | Qt::FramelessWindowHint),
  42         point_(),
  43         pos_(Left)
  44 {
  45 }
  46
  47 const QPoint& Popup::point() const
  48 {
  49         return point_;
  50 }
  51
  52 Popup::Position Popup::position() const
  53 {
  54         return pos_;
  55 }
  56
  57 void Popup::set_position(const QPoint point, Position pos)
  58 {
  59         point_ = point, pos_ = pos;
  60
  61         setContentsMargins(
  62                 MarginWidth + ((pos == Right) ? ArrowLength : 0),
  63                 MarginWidth + ((pos == Bottom) ? ArrowLength : 0),
  64                 MarginWidth + ((pos == Left) ? ArrowLength : 0),
  65                 MarginWidth + ((pos == Top) ? ArrowLength : 0));
  66 }
  67
  68 bool Popup::eventFilter(QObject *obj, QEvent *event)
  69 {
  70         QKeyEvent *keyEvent;
  71
  72         (void)obj;
  73
  74         if (event->type() == QEvent::KeyPress) {
  75                 keyEvent = static_cast<QKeyEvent*>(event);
  76                 if (keyEvent->key() == Qt::Key_Enter ||
  77                     keyEvent->key() == Qt::Key_Return) {
  78                         close();
  79                         return true;
  80                 }
  81         }
  82
  83         return false;
  84 }
  85
  86 void Popup::show()
  87 {
  88         QLineEdit* le;
  89
  90         QWidget::show();
  91
  92         // We want to close the popup when the Enter key was
  93         // pressed and the first editable widget had focus.
  94         if ((le = this->findChild<QLineEdit*>())) {
  95
  96                 // For combo boxes we need to hook into the parent of
  97                 // the line edit (i.e. the QComboBox). For edit boxes
  98                 // we hook into the widget directly.
  99                 if (le->parent()->metaObject()->className() ==
 100                                 this->metaObject()->className())
 101                         le->installEventFilter(this);
 102                 else
 103                         le->parent()->installEventFilter(this);
 104
 105                 le->selectAll();
 106                 le->setFocus();
 107         }
 108 }
 109
 110 bool Popup::space_for_arrow() const
 111 {
 112         // Check if there is room for the arrow
 113         switch (pos_) {
 114         case Right:
 115                 if (point_.x() > x())
 116                         return false;
 117                 return true;
 118
 119         case Bottom:
 120                 if (point_.y() > y())
 121                         return false;
 122                 return true;
 123
 124         case Left:
 125                 if (point_.x() < (x() + width()))
 126                         return false;
 127                 return true;
 128
 129         case Top:
 130                 if (point_.y() < (y() + height()))
 131                         return false;
 132                 return true;
 133         }
 134
 135         return true;
 136 }
 137
 138 QPolygon Popup::arrow_polygon() const
 139 {
 140         QPolygon poly;
 141
 142         const QPoint p = mapFromGlobal(point_);
 143         const int l = ArrowLength + ArrowOverlap;
 144
 145         switch (pos_) {
 146         case Right:
 147                 poly << QPoint(p.x() + l, p.y() - l);
 148                 break;
 149
 150         case Bottom:
 151                 poly << QPoint(p.x() - l, p.y() + l);
 152                 break;
 153
 154         case Left:
 155         case Top:
 156                 poly << QPoint(p.x() - l, p.y() - l);
 157                 break;
 158         }
 159
 160         poly << p;
 161
 162         switch (pos_) {
 163         case Right:
 164         case Bottom:
 165                 poly << QPoint(p.x() + l, p.y() + l);
 166                 break;
 167
 168         case Left:
 169                 poly << QPoint(p.x() - l, p.y() + l);
 170                 break;
 171
 172         case Top:
 173                 poly << QPoint(p.x() + l, p.y() - l);
 174                 break;
 175         }
 176
 177         return poly;
 178 }
 179
 180 QRegion Popup::arrow_region() const
 181 {
 182         return QRegion(arrow_polygon());
 183 }
 184
 185 QRect Popup::bubble_rect() const
 186 {
 187         return QRect(
 188                 QPoint((pos_ == Right) ? ArrowLength : 0,
 189                         (pos_ == Bottom) ? ArrowLength : 0),
 190                 QSize(width() - ((pos_ == Left || pos_ == Right) ?
 191                                 ArrowLength : 0),
 192                         height() - ((pos_ == Top || pos_ == Bottom) ?
 193                                 ArrowLength : 0)));
 194 }
 195
 196 QRegion Popup::bubble_region() const
 197 {
 198         const QRect rect(bubble_rect());
 199
 200         const unsigned int r = MarginWidth;
 201         const unsigned int d = 2 * r;
 202         return QRegion(rect.adjusted(r, 0, -r, 0)).united(
 203                 QRegion(rect.adjusted(0, r, 0, -r))).united(
 204                 QRegion(rect.left(), rect.top(), d, d,
 205                         QRegion::Ellipse)).united(
 206                 QRegion(rect.right() - d, rect.top(), d, d,
 207                         QRegion::Ellipse)).united(
 208                 QRegion(rect.left(), rect.bottom() - d, d, d,
 209                         QRegion::Ellipse)).united(
 210                 QRegion(rect.right() - d, rect.bottom() - d, d, d,
 211                         QRegion::Ellipse));
 212 }
 213
 214 QRegion Popup::popup_region() const
 215 {
 216         if (space_for_arrow())
 217                 return arrow_region().united(bubble_region());
 218         else
 219                 return bubble_region();
 220 }
 221
 222 void Popup::reposition_widget()
 223 {
 224         QPoint o;
 225
 226         const QRect screen_rect = QApplication::desktop()->availableGeometry(
 227                 QApplication::desktop()->screenNumber(point_));
 228
 229         if (pos_ == Right || pos_ == Left)
 230                 o.ry() = -height() / 2;
 231         else
 232                 o.rx() = -width() / 2;
 233
 234         if (pos_ == Left)
 235                 o.rx() = -width();
 236         else if (pos_ == Top)
 237                 o.ry() = -height();
 238
 239         o += point_;
 240         move(max(min(o.x(), screen_rect.right() - width()),
 241                         screen_rect.left()),
 242                 max(min(o.y(), screen_rect.bottom() - height()),
 243                         screen_rect.top()));
 244 }
 245
 246 void Popup::closeEvent(QCloseEvent*)
 247 {
 248         closed();
 249 }
 250
 251 void Popup::paintEvent(QPaintEvent*)
 252 {
 253         QPainter painter(this);
 254         painter.setRenderHint(QPainter::Antialiasing);
 255
 256         const QColor outline_color(QApplication::palette().color(
 257                 QPalette::Dark));
 258
 259         // Draw the bubble
 260         const QRegion b = bubble_region();
 261         const QRegion bubble_outline = QRegion(rect()).subtracted(
 262                 b.translated(1, 0).intersected(b.translated(0, 1).intersected(
 263                 b.translated(-1, 0).intersected(b.translated(0, -1)))));
 264
 265         painter.setPen(Qt::NoPen);
 266         painter.setBrush(QApplication::palette().brush(QPalette::Window));
 267         painter.drawRect(rect());
 268
 269         // Draw the arrow
 270         if (!space_for_arrow())
 271                 return;
 272
 273         const QPoint ArrowOffsets[] = {
 274                 QPoint(1, 0), QPoint(0, -1), QPoint(-1, 0), QPoint(0, 1)};
 275
 276         const QRegion a(arrow_region());
 277         const QRegion arrow_outline = a.subtracted(
 278                 a.translated(ArrowOffsets[pos_]));
 279
 280         painter.setClipRegion(bubble_outline.subtracted(a).united(
 281                 arrow_outline));
 282         painter.setBrush(outline_color);
 283         painter.drawRect(rect());
 284 }
 285
 286 void Popup::resizeEvent(QResizeEvent*)
 287 {
 288         reposition_widget();
 289         setMask(popup_region());
 290 }
 291
 292 void Popup::mouseReleaseEvent(QMouseEvent *event)
 293 {
 294         assert(event);
 295
 296         // We need our own out-of-bounds click handler because QWidget counts
 297         // the drop-shadow region as inside the widget
 298         if (!bubble_rect().contains(event->pos()))
 299                 close();
 300 }
 301
 302 void Popup::showEvent(QShowEvent*)
 303 {
 304         reposition_widget();
 305 }
 306
 307 } // namespace widgets
 308 } // namespace pv