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