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