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 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
  25 #include <QScreen>
  26 #else
  27 #include <QDesktopWidget>
  28 #endif
  29 #include <QLineEdit>
  30 #include <QScrollBar>
  31 #include <QStyle>
  32 #include <QtGui>
  33
  34 #include "popup.hpp"
  35
  36 using std::max;
  37 using std::min;
  38
  39 namespace pv {
  40 namespace widgets {
  41
  42 const unsigned int Popup::ArrowLength = 10;
  43 const unsigned int Popup::ArrowOverlap = 3;
  44 const unsigned int Popup::MarginWidth = 6;
  45
  46
  47 QWidthAdjustingScrollArea::QWidthAdjustingScrollArea(QWidget* parent) :
  48         QScrollArea(parent)
  49 {
  50 }
  51
  52 void QWidthAdjustingScrollArea::setWidget(QWidget* w)
  53 {
  54         QScrollArea::setWidget(w);
  55         // It happens that QScrollArea already filters widget events,
  56         // but that's an implementation detail that we shouldn't rely on.
  57         w->installEventFilter(this);
  58 }
  59
  60 bool QWidthAdjustingScrollArea::eventFilter(QObject* obj, QEvent* ev)
  61 {
  62         if (obj == widget() && ev->type() == QEvent::Resize) {
  63                 if (widget()->height() > height())
  64                         setMinimumWidth(widget()->width() + qApp->style()->pixelMetric(QStyle::PM_ScrollBarExtent));
  65                 else
  66                         setMinimumWidth(widget()->width());
  67         }
  68
  69         return QScrollArea::eventFilter(obj, ev);
  70 }
  71
  72
  73 Popup::Popup(QWidget *parent) :
  74         QWidget(parent, Qt::Popup | Qt::FramelessWindowHint),
  75         point_(),
  76         pos_(Left)
  77 {
  78 }
  79
  80 const QPoint& Popup::point() const
  81 {
  82         return point_;
  83 }
  84
  85 Popup::Position Popup::position() const
  86 {
  87         return pos_;
  88 }
  89
  90 void Popup::set_position(const QPoint point, Position pos)
  91 {
  92         point_ = point, pos_ = pos;
  93
  94         setContentsMargins(
  95                 MarginWidth + ((pos == Right) ? ArrowLength : 0),
  96                 MarginWidth + ((pos == Bottom) ? ArrowLength : 0),
  97                 MarginWidth + ((pos == Left) ? ArrowLength : 0),
  98                 MarginWidth + ((pos == Top) ? ArrowLength : 0));
  99 }
 100
 101 bool Popup::eventFilter(QObject *obj, QEvent *event)
 102 {
 103         QKeyEvent *keyEvent;
 104
 105         (void)obj;
 106
 107         if (event->type() == QEvent::KeyPress) {
 108                 keyEvent = static_cast<QKeyEvent*>(event);
 109                 if (keyEvent->key() == Qt::Key_Enter ||
 110                     keyEvent->key() == Qt::Key_Return) {
 111                         close();
 112                         return true;
 113                 }
 114         }
 115
 116         return false;
 117 }
 118
 119 void Popup::show()
 120 {
 121         QLineEdit* le;
 122
 123         QWidget::show();
 124
 125         // We want to close the popup when the Enter key was
 126         // pressed and the first editable widget had focus.
 127         if ((le = this->findChild<QLineEdit*>())) {
 128
 129                 // For combo boxes we need to hook into the parent of
 130                 // the line edit (i.e. the QComboBox). For edit boxes
 131                 // we hook into the widget directly.
 132                 if (le->parent()->metaObject()->className() ==
 133                                 this->metaObject()->className())
 134                         le->installEventFilter(this);
 135                 else
 136                         le->parent()->installEventFilter(this);
 137
 138                 le->selectAll();
 139                 le->setFocus();
 140         }
 141 }
 142
 143 bool Popup::space_for_arrow() const
 144 {
 145         // Check if there is room for the arrow
 146         switch (pos_) {
 147         case Right:
 148                 if (point_.x() > x())
 149                         return false;
 150                 return true;
 151
 152         case Bottom:
 153                 if (point_.y() > y())
 154                         return false;
 155                 return true;
 156
 157         case Left:
 158                 if (point_.x() < (x() + width()))
 159                         return false;
 160                 return true;
 161
 162         case Top:
 163                 if (point_.y() < (y() + height()))
 164                         return false;
 165                 return true;
 166         }
 167
 168         return true;
 169 }
 170
 171 QPolygon Popup::arrow_polygon() const
 172 {
 173         QPolygon poly;
 174
 175         const QPoint p = mapFromGlobal(point_);
 176         const int l = ArrowLength + ArrowOverlap;
 177
 178         switch (pos_) {
 179         case Right:
 180                 poly << QPoint(p.x() + l, p.y() - l);
 181                 break;
 182
 183         case Bottom:
 184                 poly << QPoint(p.x() - l, p.y() + l);
 185                 break;
 186
 187         case Left:
 188         case Top:
 189                 poly << QPoint(p.x() - l, p.y() - l);
 190                 break;
 191         }
 192
 193         poly << p;
 194
 195         switch (pos_) {
 196         case Right:
 197         case Bottom:
 198                 poly << QPoint(p.x() + l, p.y() + l);
 199                 break;
 200
 201         case Left:
 202                 poly << QPoint(p.x() - l, p.y() + l);
 203                 break;
 204
 205         case Top:
 206                 poly << QPoint(p.x() + l, p.y() - l);
 207                 break;
 208         }
 209
 210         return poly;
 211 }
 212
 213 QRegion Popup::arrow_region() const
 214 {
 215         return QRegion(arrow_polygon());
 216 }
 217
 218 QRect Popup::bubble_rect() const
 219 {
 220         return QRect(
 221                 QPoint((pos_ == Right) ? ArrowLength : 0,
 222                         (pos_ == Bottom) ? ArrowLength : 0),
 223                 QSize(width() - ((pos_ == Left || pos_ == Right) ?
 224                                 ArrowLength : 0),
 225                         height() - ((pos_ == Top || pos_ == Bottom) ?
 226                                 ArrowLength : 0)));
 227 }
 228
 229 QRegion Popup::bubble_region() const
 230 {
 231         const QRect rect(bubble_rect());
 232
 233         const unsigned int r = MarginWidth;
 234         const unsigned int d = 2 * r;
 235         return QRegion(rect.adjusted(r, 0, -r, 0)).united(
 236                 QRegion(rect.adjusted(0, r, 0, -r))).united(
 237                 QRegion(rect.left(), rect.top(), d, d,
 238                         QRegion::Ellipse)).united(
 239                 QRegion(rect.right() - d, rect.top(), d, d,
 240                         QRegion::Ellipse)).united(
 241                 QRegion(rect.left(), rect.bottom() - d, d, d,
 242                         QRegion::Ellipse)).united(
 243                 QRegion(rect.right() - d, rect.bottom() - d, d, d,
 244                         QRegion::Ellipse));
 245 }
 246
 247 QRegion Popup::popup_region() const
 248 {
 249         if (space_for_arrow())
 250                 return arrow_region().united(bubble_region());
 251         else
 252                 return bubble_region();
 253 }
 254
 255 void Popup::reposition_widget()
 256 {
 257         QPoint o;
 258
 259 #if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
 260         const QRect screen_rect = QApplication::screenAt(point_)->availableGeometry();
 261 #else
 262         const QRect screen_rect = QApplication::desktop()->availableGeometry(
 263                 QApplication::desktop()->screenNumber(point_));
 264 #endif
 265
 266         if (pos_ == Right || pos_ == Left)
 267                 o.ry() = -height() / 2;
 268         else
 269                 o.rx() = -width() / 2;
 270
 271         if (pos_ == Left)
 272                 o.rx() = -width();
 273         else if (pos_ == Top)
 274                 o.ry() = -height();
 275
 276         o += point_;
 277         move(max(min(o.x(), screen_rect.right() - width()),
 278                         screen_rect.left()),
 279                 max(min(o.y(), screen_rect.bottom() - height()),
 280                         screen_rect.top()));
 281 }
 282
 283 void Popup::closeEvent(QCloseEvent*)
 284 {
 285         closed();
 286 }
 287
 288 void Popup::paintEvent(QPaintEvent*)
 289 {
 290         QPainter painter(this);
 291         painter.setRenderHint(QPainter::Antialiasing);
 292
 293         const QColor outline_color(QApplication::palette().color(
 294                 QPalette::Dark));
 295
 296         // Draw the bubble
 297         const QRegion b = bubble_region();
 298         const QRegion bubble_outline = QRegion(rect()).subtracted(
 299                 b.translated(1, 0).intersected(b.translated(0, 1).intersected(
 300                 b.translated(-1, 0).intersected(b.translated(0, -1)))));
 301
 302         painter.setPen(Qt::NoPen);
 303         painter.setBrush(QApplication::palette().brush(QPalette::Window));
 304         painter.drawRect(rect());
 305
 306         // Draw the arrow
 307         if (!space_for_arrow())
 308                 return;
 309
 310         const QPoint ArrowOffsets[] = {
 311                 QPoint(1, 0), QPoint(0, -1), QPoint(-1, 0), QPoint(0, 1)};
 312
 313         const QRegion a(arrow_region());
 314         const QRegion arrow_outline = a.subtracted(
 315                 a.translated(ArrowOffsets[pos_]));
 316
 317         painter.setClipRegion(bubble_outline.subtracted(a).united(
 318                 arrow_outline));
 319         painter.setBrush(outline_color);
 320         painter.drawRect(rect());
 321 }
 322
 323 void Popup::resizeEvent(QResizeEvent*)
 324 {
 325         reposition_widget();
 326         setMask(popup_region());
 327 }
 328
 329 void Popup::mouseReleaseEvent(QMouseEvent *event)
 330 {
 331         assert(event);
 332
 333         // We need our own out-of-bounds click handler because QWidget counts
 334         // the drop-shadow region as inside the widget
 335         if (!bubble_rect().contains(event->pos()))
 336                 close();
 337 }
 338
 339 void Popup::showEvent(QShowEvent*)
 340 {
 341         reposition_widget();
 342 }
 343
 344 } // namespace widgets
 345 } // namespace pv