src/frontends/qt4/GuiWorkArea.cpp

   1 /**
   2  * \file GuiWorkArea.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author John Levon
   7  * \author Abdelrazak Younes
   8  *
   9  * Full author contact details are available in file CREDITS.
  10  */
  11
  12 #include <config.h>
  13
  14 #include "GuiWorkArea.h"
  15
  16 #include "GuiApplication.h"
  17 #include "QLPainter.h"
  18 #include "QKeySymbol.h"
  19 #include "qt_helpers.h"
  20
  21 #include "frontends/LyXView.h"
  22
  23 #include "BufferView.h"
  24 #include "Color.h"
  25 #include "debug.h"
  26 #include "FuncRequest.h"
  27 #include "LyXRC.h"
  28 #include "rowpainter.h"
  29 #include "version.h"
  30
  31 #include "support/filetools.h" // LibFileSearch
  32 #include "support/convert.h"
  33
  34 #include "graphics/GraphicsImage.h"
  35 #include "graphics/GraphicsLoader.h"
  36
  37 #include <QInputContext>
  38 #include <QLayout>
  39 #include <QMainWindow>
  40 #include <QPainter>
  41 #include <QScrollBar>
  42 #include <QTimer>
  43
  44 #include <boost/bind.hpp>
  45 #include <boost/current_function.hpp>
  46
  47 #ifdef Q_WS_X11
  48 #include <QX11Info>
  49 extern "C" int XEventsQueued(Display *display, int mode);
  50 #endif
  51
  52 #ifdef Q_WS_WIN
  53 int const CursorWidth = 2;
  54 #else
  55 int const CursorWidth = 1;
  56 #endif
  57
  58
  59 using std::endl;
  60 using std::string;
  61
  62 namespace lyx {
  63
  64 using support::FileName;
  65
  66 /// return the LyX key state from Qt's
  67 static key_modifier::state q_key_state(Qt::KeyboardModifiers state)
  68 {
  69         key_modifier::state k = key_modifier::none;
  70         if (state & Qt::ControlModifier)
  71                 k |= key_modifier::ctrl;
  72         if (state & Qt::ShiftModifier)
  73                 k |= key_modifier::shift;
  74         if (state & Qt::AltModifier || state & Qt::MetaModifier)
  75                 k |= key_modifier::alt;
  76         return k;
  77 }
  78
  79
  80 /// return the LyX mouse button state from Qt's
  81 static mouse_button::state q_button_state(Qt::MouseButton button)
  82 {
  83         mouse_button::state b = mouse_button::none;
  84         switch (button) {
  85                 case Qt::LeftButton:
  86                         b = mouse_button::button1;
  87                         break;
  88                 case Qt::MidButton:
  89                         b = mouse_button::button2;
  90                         break;
  91                 case Qt::RightButton:
  92                         b = mouse_button::button3;
  93                         break;
  94                 default:
  95                         break;
  96         }
  97         return b;
  98 }
  99
 100
 101 /// return the LyX mouse button state from Qt's
 102 mouse_button::state q_motion_state(Qt::MouseButtons state)
 103 {
 104         mouse_button::state b = mouse_button::none;
 105         if (state & Qt::LeftButton)
 106                 b |= mouse_button::button1;
 107         if (state & Qt::MidButton)
 108                 b |= mouse_button::button2;
 109         if (state & Qt::RightButton)
 110                 b |= mouse_button::button3;
 111         return b;
 112 }
 113
 114
 115 namespace frontend {
 116
 117 class CursorWidget {
 118 public:
 119         CursorWidget() {}
 120
 121         void draw(QPainter & painter)
 122         {
 123                 if (show_ && rect_.isValid()) {
 124                         switch (shape_) {
 125                         case L_SHAPE:
 126                                 painter.fillRect(rect_.x(), rect_.y(), CursorWidth, rect_.height(), color_);
 127                                 painter.setPen(color_);
 128                                 painter.drawLine(rect_.bottomLeft().x() + CursorWidth, rect_.bottomLeft().y(),
 129                                                                                                  rect_.bottomRight().x(), rect_.bottomLeft().y());
 130                                 break;
 131
 132                         case REVERSED_L_SHAPE:
 133                                 painter.fillRect(rect_.x() + rect_.height() / 3, rect_.y(), CursorWidth, rect_.height(), color_);
 134                                 painter.setPen(color_);
 135                                 painter.drawLine(rect_.bottomRight().x() - CursorWidth, rect_.bottomLeft().y(),
 136                                                                                                          rect_.bottomLeft().x(), rect_.bottomLeft().y());
 137                                 break;
 138
 139                         default:
 140                                 painter.fillRect(rect_, color_);
 141                                 break;
 142                         }
 143                 }
 144         }
 145
 146         void update(int x, int y, int h, CursorShape shape)
 147         {
 148                 color_ = guiApp->colorCache().get(Color::cursor);
 149                 shape_ = shape;
 150                 switch (shape) {
 151                 case L_SHAPE:
 152                         rect_ = QRect(x, y, CursorWidth + h / 3, h);
 153                         break;
 154                 case REVERSED_L_SHAPE:
 155                         rect_ = QRect(x - h / 3, y, CursorWidth + h / 3, h);
 156                         break;
 157                 default:
 158                         rect_ = QRect(x, y, CursorWidth, h);
 159                         break;
 160                 }
 161         }
 162
 163         void show(bool set_show = true) { show_ = set_show; }
 164         void hide() { show_ = false; }
 165
 166         QRect const & rect() { return rect_; }
 167
 168 private:
 169         ///
 170         CursorShape shape_;
 171         ///
 172         bool show_;
 173         ///
 174         QColor color_;
 175         ///
 176         QRect rect_;
 177 };
 178
 179
 180 // This is a 'heartbeat' generating synthetic mouse move events when the
 181 // cursor is at the top or bottom edge of the viewport. One scroll per 0.2 s
 182 SyntheticMouseEvent::SyntheticMouseEvent()
 183         : timeout(200), restart_timeout(true),
 184           x_old(-1), y_old(-1), scrollbar_value_old(-1.0)
 185 {}
 186
 187
 188 GuiWorkArea::GuiWorkArea(int w, int h, int id, LyXView & lyx_view)
 189         : WorkArea(id, lyx_view), need_resize_(false), schedule_redraw_(false),
 190           preedit_lines_(1)
 191 {
 192         screen_ = QPixmap(viewport()->width(), viewport()->height());
 193         cursor_ = new frontend::CursorWidget();
 194         cursor_->hide();
 195
 196         setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
 197         setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 198         setAcceptDrops(true);
 199         setMouseTracking(true);
 200         setMinimumSize(100, 70);
 201
 202         viewport()->setAutoFillBackground(false);
 203         // We don't need double-buffering nor SystemBackground on
 204         // the viewport because we have our own backing pixmap.
 205         viewport()->setAttribute(Qt::WA_NoSystemBackground);
 206
 207         setFocusPolicy(Qt::WheelFocus);
 208
 209         viewport()->setCursor(Qt::IBeamCursor);
 210
 211         resize(w, h);
 212
 213         synthetic_mouse_event_.timeout.timeout.connect(
 214                 boost::bind(&GuiWorkArea::generateSyntheticMouseEvent,
 215                             this));
 216
 217         // Initialize the vertical Scroll Bar
 218         QObject::connect(verticalScrollBar(), SIGNAL(actionTriggered(int)),
 219                 this, SLOT(adjustViewWithScrollBar(int)));
 220
 221         // disable context menu for the scrollbar
 222         verticalScrollBar()->setContextMenuPolicy(Qt::NoContextMenu);
 223
 224         // PageStep only depends on the viewport height.
 225         verticalScrollBar()->setPageStep(viewport()->height());
 226
 227         LYXERR(Debug::GUI) << BOOST_CURRENT_FUNCTION
 228                 << "\n Area width\t" << width()
 229                 << "\n Area height\t" << height()
 230                 << "\n viewport width\t" << viewport()->width()
 231                 << "\n viewport height\t" << viewport()->height()
 232                 << endl;
 233
 234         // Enables input methods for asian languages.
 235         // Must be set when creating custom text editing widgets.
 236         setAttribute(Qt::WA_InputMethodEnabled, true);
 237 }
 238
 239
 240 void GuiWorkArea::setScrollbarParams(int h, int scroll_pos, int scroll_line_step)
 241 {
 242         if (verticalScrollBarPolicy() != Qt::ScrollBarAlwaysOn)
 243                 setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
 244
 245         verticalScrollBar()->setTracking(false);
 246
 247         // do what cursor movement does (some grey)
 248         h += height() / 4;
 249         int scroll_max_ = std::max(0, h - height());
 250
 251         verticalScrollBar()->setRange(0, scroll_max_);
 252         verticalScrollBar()->setSliderPosition(scroll_pos);
 253         verticalScrollBar()->setSingleStep(scroll_line_step);
 254         verticalScrollBar()->setValue(scroll_pos);
 255
 256         verticalScrollBar()->setTracking(true);
 257 }
 258
 259
 260 void GuiWorkArea::adjustViewWithScrollBar(int)
 261 {
 262         scrollBufferView(verticalScrollBar()->sliderPosition());
 263         QApplication::syncX();
 264 }
 265
 266
 267 void GuiWorkArea::focusInEvent(QFocusEvent * /*event*/)
 268 {
 269         // No need to do anything if we didn't change views...
 270 //      if (theApp() == 0 || &lyx_view_ == theApp()->currentView())
 271 //              return;
 272
 273         theApp()->setCurrentView(lyx_view_);
 274
 275         // Repaint the whole screen.
 276         // Note: this is different from redraw() as only the backing pixmap
 277         // will be redrawn, which is cheap.
 278         viewport()->repaint();
 279
 280         // FIXME: it would be better to send a signal "newBuffer()"
 281         // in BufferList that could be connected to the different tabbars.
 282         lyx_view_.updateTab();
 283
 284         startBlinkingCursor();
 285 }
 286
 287
 288 void GuiWorkArea::focusOutEvent(QFocusEvent * /*event*/)
 289 {
 290         stopBlinkingCursor();
 291 }
 292
 293
 294 void GuiWorkArea::mousePressEvent(QMouseEvent * e)
 295 {
 296         if (dc_event_.active && dc_event_ == *e) {
 297                 dc_event_.active = false;
 298                 FuncRequest cmd(LFUN_MOUSE_TRIPLE,
 299                         e->x(), e->y(),
 300                         q_button_state(e->button()));
 301                 dispatch(cmd);
 302                 return;
 303         }
 304
 305         inputContext()->reset();
 306
 307         FuncRequest const cmd(LFUN_MOUSE_PRESS, e->x(), e->y(),
 308                 q_button_state(e->button()));
 309         dispatch(cmd, q_key_state(e->modifiers()));
 310 }
 311
 312
 313 void GuiWorkArea::mouseReleaseEvent(QMouseEvent * e)
 314 {
 315         if (synthetic_mouse_event_.timeout.running())
 316                 synthetic_mouse_event_.timeout.stop();
 317
 318         FuncRequest const cmd(LFUN_MOUSE_RELEASE, e->x(), e->y(),
 319                               q_button_state(e->button()));
 320         dispatch(cmd);
 321 }
 322
 323
 324 void GuiWorkArea::mouseMoveEvent(QMouseEvent * e)
 325 {
 326         // we kill the triple click if we move
 327         doubleClickTimeout();
 328         FuncRequest cmd(LFUN_MOUSE_MOTION, e->x(), e->y(),
 329                               q_motion_state(e->buttons()));
 330
 331         // If we're above or below the work area...
 332         if (e->y() <= 20 || e->y() >= viewport()->height() - 20) {
 333                 // Make sure only a synthetic event can cause a page scroll,
 334                 // so they come at a steady rate:
 335                 if (e->y() <= 20)
 336                         // _Force_ a scroll up:
 337                         cmd.y = -40;
 338                 else
 339                         cmd.y = viewport()->height();
 340                 // Store the event, to be handled when the timeout expires.
 341                 synthetic_mouse_event_.cmd = cmd;
 342
 343                 if (synthetic_mouse_event_.timeout.running())
 344                         // Discard the event. Note that it _may_ be handled
 345                         // when the timeout expires if
 346                         // synthetic_mouse_event_.cmd has not been overwritten.
 347                         // Ie, when the timeout expires, we handle the
 348                         // most recent event but discard all others that
 349                         // occurred after the one used to start the timeout
 350                         // in the first place.
 351                         return;
 352                 else {
 353                         synthetic_mouse_event_.restart_timeout = true;
 354                         synthetic_mouse_event_.timeout.start();
 355                         // Fall through to handle this event...
 356                 }
 357
 358         } else if (synthetic_mouse_event_.timeout.running()) {
 359                 // Store the event, to be possibly handled when the timeout
 360                 // expires.
 361                 // Once the timeout has expired, normal control is returned
 362                 // to mouseMoveEvent (restart_timeout = false).
 363                 // This results in a much smoother 'feel' when moving the
 364                 // mouse back into the work area.
 365                 synthetic_mouse_event_.cmd = cmd;
 366                 synthetic_mouse_event_.restart_timeout = false;
 367                 return;
 368         }
 369
 370         // Has anything changed on-screen since the last QMouseEvent
 371         // was received?
 372         double const scrollbar_value = verticalScrollBar()->value();
 373         if (e->x() != synthetic_mouse_event_.x_old ||
 374             e->y() != synthetic_mouse_event_.y_old ||
 375             scrollbar_value != synthetic_mouse_event_.scrollbar_value_old) {
 376                 // Yes it has. Store the params used to check this.
 377                 synthetic_mouse_event_.x_old = e->x();
 378                 synthetic_mouse_event_.y_old = e->y();
 379                 synthetic_mouse_event_.scrollbar_value_old = scrollbar_value;
 380
 381                 // ... and dispatch the event to the LyX core.
 382                 dispatch(cmd);
 383         }
 384 }
 385
 386
 387 void GuiWorkArea::wheelEvent(QWheelEvent * e)
 388 {
 389         // Wheel rotation by one notch results in a delta() of 120 (see
 390         // documentation of QWheelEvent)
 391         int const lines = qApp->wheelScrollLines() * e->delta() / 120;
 392         verticalScrollBar()->setValue(verticalScrollBar()->value() -
 393                         lines *  verticalScrollBar()->singleStep());
 394         adjustViewWithScrollBar();
 395 }
 396
 397
 398 void GuiWorkArea::generateSyntheticMouseEvent()
 399 {
 400 // Set things off to generate the _next_ 'pseudo' event.
 401         if (synthetic_mouse_event_.restart_timeout)
 402                 synthetic_mouse_event_.timeout.start();
 403
 404         // Has anything changed on-screen since the last timeout signal
 405         // was received?
 406         double const scrollbar_value = verticalScrollBar()->value();
 407         if (scrollbar_value != synthetic_mouse_event_.scrollbar_value_old) {
 408                 // Yes it has. Store the params used to check this.
 409                 synthetic_mouse_event_.scrollbar_value_old = scrollbar_value;
 410
 411                 // ... and dispatch the event to the LyX core.
 412                 dispatch(synthetic_mouse_event_.cmd);
 413         }
 414 }
 415
 416
 417 void GuiWorkArea::keyPressEvent(QKeyEvent * e)
 418 {
 419         // do nothing if there are other events
 420         // (the auto repeated events come too fast)
 421         // \todo FIXME: remove hard coded Qt keys, process the key binding
 422 #ifdef Q_WS_X11
 423         if (XEventsQueued(QX11Info::display(), 0) > 1 && e->isAutoRepeat()
 424                         && (Qt::Key_PageDown || Qt::Key_PageUp)) {
 425                 LYXERR(Debug::KEY)
 426                         << BOOST_CURRENT_FUNCTION << endl
 427                         << "system is busy: scroll key event ignored" << endl;
 428                 e->ignore();
 429                 return;
 430         }
 431 #endif
 432
 433         LYXERR(Debug::KEY) << BOOST_CURRENT_FUNCTION
 434                 << " count=" << e->count()
 435                 << " text=" << fromqstr(e->text())
 436                 << " isAutoRepeat=" << e->isAutoRepeat()
 437                 << " key=" << e->key()
 438                 << endl;
 439
 440         boost::shared_ptr<QKeySymbol> sym(new QKeySymbol);
 441         sym->set(e);
 442         processKeySym(sym, q_key_state(e->modifiers()));
 443 }
 444
 445 void GuiWorkArea::doubleClickTimeout() {
 446         dc_event_.active = false;
 447 }
 448
 449 void GuiWorkArea::mouseDoubleClickEvent(QMouseEvent * e)
 450 {
 451         dc_event_ = double_click(e);
 452         QTimer::singleShot(QApplication::doubleClickInterval(), this,
 453                            SLOT(doubleClickTimeout()));
 454         FuncRequest cmd(LFUN_MOUSE_DOUBLE,
 455                         e->x(), e->y(),
 456                         q_button_state(e->button()));
 457         dispatch(cmd);
 458 }
 459
 460
 461 void GuiWorkArea::resizeEvent(QResizeEvent * ev)
 462 {
 463         QAbstractScrollArea::resizeEvent(ev);
 464         need_resize_ = true;
 465 }
 466
 467
 468 void GuiWorkArea::update(int x, int y, int w, int h)
 469 {
 470         viewport()->repaint(x, y, w, h);
 471 }
 472
 473
 474 void GuiWorkArea::doGreyOut(QLPainter & pain)
 475 {
 476         pain.fillRectangle(0, 0, width(), height(),
 477                 Color::bottomarea);
 478
 479         //if (!lyxrc.show_banner)
 480         //      return;
 481         LYXERR(Debug::GUI) << "show banner: " << lyxrc.show_banner << endl;
 482         /// The text to be written on top of the pixmap
 483         QString const text = lyx_version ? QString(lyx_version) : qt_("unknown version");
 484         FileName const file = support::libFileSearch("images", "banner", "png");
 485         if (file.empty())
 486                 return;
 487
 488         QPixmap pm(toqstr(file.absFilename()));
 489         if (!pm) {
 490                 lyxerr << "could not load splash screen: '" << file << "'" << endl;
 491                 return;
 492         }
 493
 494         QFont font;
 495         // The font used to display the version info
 496         font.setStyleHint(QFont::SansSerif);
 497         font.setWeight(QFont::Bold);
 498         font.setPointSize(convert<int>(lyxrc.font_sizes[Font::SIZE_LARGE]));
 499
 500         int const w = pm.width();
 501         int const h = pm.height();
 502
 503         int x = (width() - w) / 2;
 504         int y = (height() - h) / 2;
 505
 506         pain.drawPixmap(x, y, pm);
 507
 508         x += 260;
 509         y += 270;
 510
 511         pain.setPen(QColor(255, 255, 0));
 512         pain.setFont(font);
 513         pain.drawText(x, y, text);
 514 }
 515
 516
 517 void GuiWorkArea::paintEvent(QPaintEvent * ev)
 518 {
 519         QRect const rc = ev->rect();
 520         /*
 521         LYXERR(Debug::PAINTING) << "paintEvent begin: x: " << rc.x()
 522                 << " y: " << rc.y()
 523                 << " w: " << rc.width()
 524                 << " h: " << rc.height() << endl;
 525         */
 526
 527         if (need_resize_) {
 528                 verticalScrollBar()->setPageStep(viewport()->height());
 529                 screen_ = QPixmap(viewport()->width(), viewport()->height());
 530                 resizeBufferView();
 531                 updateScreen();
 532                 WorkArea::hideCursor();
 533                 WorkArea::showCursor();
 534                 need_resize_ = false;
 535         }
 536
 537         QPainter pain(viewport());
 538         pain.drawPixmap(rc, screen_, rc);
 539         cursor_->draw(pain);
 540 }
 541
 542
 543 void GuiWorkArea::expose(int x, int y, int w, int h)
 544 {
 545         updateScreen();
 546         update(x, y, w, h);
 547 }
 548
 549
 550 void GuiWorkArea::updateScreen()
 551 {
 552         QLPainter pain(&screen_);
 553
 554         if (greyed_out_) {
 555                 LYXERR(Debug::GUI) << "splash screen requested" << endl;
 556                 verticalScrollBar()->hide();
 557                 doGreyOut(pain);
 558                 return;
 559         }
 560
 561         verticalScrollBar()->show();
 562         paintText(*buffer_view_, pain);
 563 }
 564
 565
 566 void GuiWorkArea::showCursor(int x, int y, int h, CursorShape shape)
 567 {
 568         if (schedule_redraw_) {
 569                 if (buffer_view_ && buffer_view_->buffer()) {
 570                         buffer_view_->update(Update::Force);
 571                         updateScreen();
 572                         viewport()->update(QRect(0, 0, viewport()->width(), viewport()->height()));
 573                 }
 574                 schedule_redraw_ = false;
 575                 // Show the cursor immediately after the update.
 576                 hideCursor();
 577                 toggleCursor();
 578                 return;
 579         }
 580
 581         cursor_->update(x, y, h, shape);
 582         cursor_->show();
 583         viewport()->update(cursor_->rect());
 584 }
 585
 586
 587 void GuiWorkArea::removeCursor()
 588 {
 589         cursor_->hide();
 590         //if (!qApp->focusWidget())
 591                 viewport()->update(cursor_->rect());
 592 }
 593
 594
 595 void GuiWorkArea::inputMethodEvent(QInputMethodEvent * e)
 596 {
 597         QString const & commit_string = e->commitString();
 598         docstring const & preedit_string
 599                 = qstring_to_ucs4(e->preeditString());
 600
 601         if(greyed_out_) {
 602                 e->ignore();
 603                 return;
 604         }
 605
 606         if (!commit_string.isEmpty()) {
 607
 608                 LYXERR(Debug::KEY) << BOOST_CURRENT_FUNCTION
 609                         << " preeditString =" << fromqstr(e->preeditString())
 610                         << " commitString  =" << fromqstr(e->commitString())
 611                         << endl;
 612
 613                 int key = 0;
 614
 615                 // FIXME Iwami 04/01/07: we should take care also of UTF16 surrogates here.
 616                 for (int i = 0; i < commit_string.size(); ++i) {
 617                         QKeyEvent ev(QEvent::KeyPress, key, Qt::NoModifier, commit_string[i]);
 618                         keyPressEvent(&ev);
 619                 }
 620         }
 621
 622         // Hide the cursor during the kana-kanji transformation.
 623         if (preedit_string.empty())
 624                 startBlinkingCursor();
 625         else
 626                 stopBlinkingCursor();
 627
 628         // last_width : for checking if last preedit string was/wasn't empty.
 629         static bool last_width = false;
 630         if (!last_width && preedit_string.empty()) {
 631                 // if last_width is last length of preedit string.
 632                 e->accept();
 633                 return;
 634         }
 635
 636         QLPainter pain(&screen_);
 637         buffer_view_->updateMetrics(false);
 638         paintText(*buffer_view_, pain);
 639         Font font = buffer_view_->cursor().getFont();
 640         FontMetrics const & fm = theFontMetrics(font);
 641         int height = fm.maxHeight();
 642         int cur_x = cursor_->rect().left();
 643         int cur_y = cursor_->rect().bottom();
 644
 645         // redraw area of preedit string.
 646         update(0, cur_y - height, GuiWorkArea::width(),
 647                 (height + 1) * preedit_lines_);
 648
 649         if (preedit_string.empty()) {
 650                 last_width = false;
 651                 preedit_lines_ = 1;
 652                 e->accept();
 653                 return;
 654         }
 655         last_width = true;
 656
 657         // att : stores an IM attribute.
 658         QList<QInputMethodEvent::Attribute> const & att = e->attributes();
 659
 660         // get attributes of input method cursor.
 661         // cursor_pos : cursor position in preedit string.
 662         size_t cursor_pos = 0;
 663         bool cursor_is_visible = false;
 664         for (int i = 0; i < att.size(); ++i) {
 665                 if (att.at(i).type == QInputMethodEvent::Cursor) {
 666                         cursor_pos = att.at(i).start;
 667                         cursor_is_visible = att.at(i).length != 0;
 668                         break;
 669                 }
 670         }
 671
 672         size_t preedit_length = preedit_string.length();
 673
 674         // get position of selection in input method.
 675         // FIXME: isn't there a way to do this simplier?
 676         // rStart : cursor position in selected string in IM.
 677         size_t rStart = 0;
 678         // rLength : selected string length in IM.
 679         size_t rLength = 0;
 680         if (cursor_pos < preedit_length) {
 681                 for (int i = 0; i < att.size(); ++i) {
 682                         if (att.at(i).type == QInputMethodEvent::TextFormat) {
 683                                 if (att.at(i).start <= int(cursor_pos)
 684                                         && int(cursor_pos) < att.at(i).start + att.at(i).length) {
 685                                                 rStart = att.at(i).start;
 686                                                 rLength = att.at(i).length;
 687                                                 if (!cursor_is_visible)
 688                                                         cursor_pos += rLength;
 689                                                 break;
 690                                 }
 691                         }
 692                 }
 693         }
 694         else {
 695                 rStart = cursor_pos;
 696                 rLength = 0;
 697         }
 698
 699         int const right_margin = rightMargin();
 700         Painter::preedit_style ps;
 701         // Most often there would be only one line:
 702         preedit_lines_ = 1;
 703         for (size_t pos = 0; pos != preedit_length; ++pos) {
 704                 char_type const typed_char = preedit_string[pos];
 705                 // reset preedit string style
 706                 ps = Painter::preedit_default;
 707
 708                 // if we reached the right extremity of the screen, go to next line.
 709                 if (cur_x + fm.width(typed_char) > GuiWorkArea::width() - right_margin) {
 710                         cur_x = right_margin;
 711                         cur_y += height + 1;
 712                         ++preedit_lines_;
 713                 }
 714                 // preedit strings are displayed with dashed underline
 715                 // and partial strings are displayed white on black indicating
 716                 // that we are in selecting mode in the input method.
 717                 // FIXME: rLength == preedit_length is not a changing condition
 718                 // FIXME: should be put out of the loop.
 719                 if (pos >= rStart
 720                         && pos < rStart + rLength
 721                         && !(cursor_pos < rLength && rLength == preedit_length))
 722                         ps = Painter::preedit_selecting;
 723
 724                 if (pos == cursor_pos
 725                         && (cursor_pos < rLength && rLength == preedit_length))
 726                         ps = Painter::preedit_cursor;
 727
 728                 // draw one character and update cur_x.
 729                 cur_x += pain.preeditText(cur_x, cur_y, typed_char, font, ps);
 730         }
 731
 732         // update the preedit string screen area.
 733         update(0, cur_y - preedit_lines_*height, GuiWorkArea::width(),
 734                 (height + 1) * preedit_lines_);
 735
 736         // Don't forget to accept the event!
 737         e->accept();
 738 }
 739
 740
 741 QVariant GuiWorkArea::inputMethodQuery(Qt::InputMethodQuery query) const
 742 {
 743         QRect cur_r(0,0,0,0);
 744         switch (query) {
 745                 // this is the CJK-specific composition window position.
 746                 case Qt::ImMicroFocus:
 747                         cur_r = cursor_->rect();
 748                         if (preedit_lines_ != 1)
 749                                 cur_r.moveLeft(10);
 750                         cur_r.moveBottom(cur_r.bottom() + cur_r.height() * preedit_lines_);
 751                         // return lower right of cursor in LyX.
 752                         return cur_r;
 753                 default:
 754                         return QWidget::inputMethodQuery(query);
 755         }
 756 }
 757
 758 } // namespace frontend
 759 } // namespace lyx
 760
 761 #include "GuiWorkArea_moc.cpp"