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
  22 #include <assert.h>
  23
  24 #include <QtGui>
  25 #include <QApplication>
  26 #include <QDesktopWidget>
  27 #include <QLineEdit>
  28
  29 #include "popup.hpp"
  30
  31 using std::max;
  32 using std::min;
  33
  34 namespace pv {
  35 namespace widgets {
  36
  37 const unsigned int Popup::ArrowLength = 10;
  38 const unsigned int Popup::ArrowOverlap = 3;
  39 const unsigned int Popup::MarginWidth = 6;
  40
  41 Popup::Popup(QWidget *parent) :
  42         QWidget(parent, Qt::Popup | Qt::FramelessWindowHint),
  43         point_(),
  44         pos_(Left)
  45 {
  46 }
  47
  48 const QPoint& Popup::point() const
  49 {
  50         return point_;
  51 }
  52
  53 Popup::Position Popup::position() const
  54 {
  55         return pos_;
  56 }
  57
  58 void Popup::set_position(const QPoint point, Position pos)
  59 {
  60         point_ = point, pos_ = pos;
  61
  62         setContentsMargins(
  63                 MarginWidth + ((pos == Right) ? ArrowLength : 0),
  64                 MarginWidth + ((pos == Bottom) ? ArrowLength : 0),
  65                 MarginWidth + ((pos == Left) ? ArrowLength : 0),
  66                 MarginWidth + ((pos == Top) ? ArrowLength : 0));
  67 }
  68
  69 bool Popup::eventFilter(QObject *obj, QEvent *event)
  70 {
  71         QKeyEvent *keyEvent;
  72
  73         (void)obj;
  74
  75         if (event->type() == QEvent::KeyPress) {
  76                 keyEvent = static_cast<QKeyEvent*>(event);
  77                 if (keyEvent->key() == Qt::Key_Enter ||
  78                     keyEvent->key() == Qt::Key_Return) {
  79                         close();
  80                         return true;
  81                 }
  82         }
  83
  84         return false;
  85 }
  86
  87 void Popup::show()
  88 {
  89         QLineEdit* le;
  90
  91         QWidget::show();
  92
  93         // We want to close the popup when the Enter key was
  94         // pressed and the first editable widget had focus.
  95         if ((le = this->findChild<QLineEdit*>())) {
  96
  97                 // For combo boxes we need to hook into the parent of
  98                 // the line edit (i.e. the QComboBox). For edit boxes
  99                 // we hook into the widget directly.
 100                 if (le->parent()->metaObject()->className() ==
 101                                 this->metaObject()->className())
 102                         le->installEventFilter(this);
 103                 else
 104                         le->parent()->installEventFilter(this);
 105
 106                 le->selectAll();
 107                 le->setFocus();
 108         }
 109 }
 110
 111 bool Popup::space_for_arrow() const
 112 {
 113         // Check if there is room for the arrow
 114         switch (pos_) {
 115         case Right:
 116                 if (point_.x() > x())
 117                         return false;
 118                 return true;
 119
 120         case Bottom:
 121                 if (point_.y() > y())
 122                         return false;
 123                 return true;
 124
 125         case Left:
 126                 if (point_.x() < (x() + width()))
 127                         return false;
 128                 return true;
 129
 130         case Top:
 131                 if (point_.y() < (y() + height()))
 132                         return false;
 133                 return true;
 134         }
 135
 136         return true;
 137 }
 138
 139 QPolygon Popup::arrow_polygon() const
 140 {
 141         QPolygon poly;
 142
 143         const QPoint p = mapFromGlobal(point_);
 144         const int l = ArrowLength + ArrowOverlap;
 145
 146         switch (pos_) {
 147         case Right:
 148                 poly << QPoint(p.x() + l, p.y() - l);
 149                 break;
 150
 151         case Bottom:
 152                 poly << QPoint(p.x() - l, p.y() + l);
 153                 break;
 154
 155         case Left:
 156         case Top:
 157                 poly << QPoint(p.x() - l, p.y() - l);
 158                 break;
 159         }
 160
 161         poly << p;
 162
 163         switch (pos_) {
 164         case Right:
 165         case Bottom:
 166                 poly << QPoint(p.x() + l, p.y() + l);
 167                 break;
 168
 169         case Left:
 170                 poly << QPoint(p.x() - l, p.y() + l);
 171                 break;
 172
 173         case Top:
 174                 poly << QPoint(p.x() + l, p.y() - l);
 175                 break;
 176         }
 177
 178         return poly;
 179 }
 180
 181 QRegion Popup::arrow_region() const
 182 {
 183         return QRegion(arrow_polygon());
 184 }
 185
 186 QRect Popup::bubble_rect() const
 187 {
 188         return QRect(
 189                 QPoint((pos_ == Right) ? ArrowLength : 0,
 190                         (pos_ == Bottom) ? ArrowLength : 0),
 191                 QSize(width() - ((pos_ == Left || pos_ == Right) ?
 192                                 ArrowLength : 0),
 193                         height() - ((pos_ == Top || pos_ == Bottom) ?
 194                                 ArrowLength : 0)));
 195 }
 196
 197 QRegion Popup::bubble_region() const
 198 {
 199         const QRect rect(bubble_rect());
 200
 201         const unsigned int r = MarginWidth;
 202         const unsigned int d = 2 * r;
 203         return QRegion(rect.adjusted(r, 0, -r, 0)).united(
 204                 QRegion(rect.adjusted(0, r, 0, -r))).united(
 205                 QRegion(rect.left(), rect.top(), d, d,
 206                         QRegion::Ellipse)).united(
 207                 QRegion(rect.right() - d, rect.top(), d, d,
 208                         QRegion::Ellipse)).united(
 209                 QRegion(rect.left(), rect.bottom() - d, d, d,
 210                         QRegion::Ellipse)).united(
 211                 QRegion(rect.right() - d, rect.bottom() - d, d, d,
 212                         QRegion::Ellipse));
 213 }
 214
 215 QRegion Popup::popup_region() const
 216 {
 217         if (space_for_arrow())
 218                 return arrow_region().united(bubble_region());
 219         else
 220                 return bubble_region();
 221 }
 222
 223 void Popup::reposition_widget()
 224 {
 225         QPoint o;
 226
 227         const QRect screen_rect = QApplication::desktop()->availableGeometry(
 228                 QApplication::desktop()->screenNumber(point_));
 229
 230         if (pos_ == Right || pos_ == Left)
 231                 o.ry() = -height() / 2;
 232         else
 233                 o.rx() = -width() / 2;
 234
 235         if (pos_ == Left)
 236                 o.rx() = -width();
 237         else if (pos_ == Top)
 238                 o.ry() = -height();
 239
 240         o += point_;
 241         move(max(min(o.x(), screen_rect.right() - width()),
 242                         screen_rect.left()),
 243                 max(min(o.y(), screen_rect.bottom() - height()),
 244                         screen_rect.top()));
 245 }
 246
 247 void Popup::closeEvent(QCloseEvent*)
 248 {
 249         closed();
 250 }
 251
 252 void Popup::paintEvent(QPaintEvent*)
 253 {
 254         QPainter painter(this);
 255         painter.setRenderHint(QPainter::Antialiasing);
 256
 257         const QColor outline_color(QApplication::palette().color(
 258                 QPalette::Dark));
 259
 260         // Draw the bubble
 261         const QRegion b = bubble_region();
 262         const QRegion bubble_outline = QRegion(rect()).subtracted(
 263                 b.translated(1, 0).intersected(b.translated(0, 1).intersected(
 264                 b.translated(-1, 0).intersected(b.translated(0, -1)))));
 265
 266         painter.setPen(Qt::NoPen);
 267         painter.setBrush(QApplication::palette().brush(QPalette::Window));
 268         painter.drawRect(rect());
 269
 270         // Draw the arrow
 271         if (!space_for_arrow())
 272                 return;
 273
 274         const QPoint ArrowOffsets[] = {
 275                 QPoint(1, 0), QPoint(0, -1), QPoint(-1, 0), QPoint(0, 1)};
 276
 277         const QRegion a(arrow_region());
 278         const QRegion arrow_outline = a.subtracted(
 279                 a.translated(ArrowOffsets[pos_]));
 280
 281         painter.setClipRegion(bubble_outline.subtracted(a).united(
 282                 arrow_outline));
 283         painter.setBrush(outline_color);
 284         painter.drawRect(rect());
 285 }
 286
 287 void Popup::resizeEvent(QResizeEvent*)
 288 {
 289         reposition_widget();
 290         setMask(popup_region());
 291 }
 292
 293 void Popup::mouseReleaseEvent(QMouseEvent *event)
 294 {
 295         assert(event);
 296
 297         // We need our own out-of-bounds click handler because QWidget counts
 298         // the drop-shadow region as inside the widget
 299         if (!bubble_rect().contains(event->pos()))
 300                 close();
 301 }
 302
 303 void Popup::showEvent(QShowEvent*)
 304 {
 305         reposition_widget();
 306 }
 307
 308 } // namespace widgets
 309 } // namespace pv