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_X11
  52 #include <QX11Info>
  53 extern "C" int XEventsQueued(Display *display, int mode);
  54 #endif
  55
  56 #ifdef Q_WS_WIN
  57 int const CursorWidth = 2;
  58 #else
  59 int const CursorWidth = 1;
  60 #endif
  61
  62
  63 using std::endl;
  64 using std::string;
  65
  66 namespace os = lyx::support::os;
  67
  68
  69 namespace lyx {
  70
  71 using support::FileName;
  72
  73 /// return the LyX key state from Qt's
  74 static key_modifier::state q_key_state(Qt::KeyboardModifiers state)
  75 {
  76         key_modifier::state k = key_modifier::none;
  77         if (state & Qt::ControlModifier)
  78                 k |= key_modifier::ctrl;
  79         if (state & Qt::ShiftModifier)
  80                 k |= key_modifier::shift;
  81         if (state & Qt::AltModifier || state & Qt::MetaModifier)
  82                 k |= key_modifier::alt;
  83         return k;
  84 }
  85
  86
  87 /// return the LyX mouse button state from Qt's
  88 static mouse_button::state q_button_state(Qt::MouseButton button)
  89 {
  90         mouse_button::state b = mouse_button::none;
  91         switch (button) {
  92                 case Qt::LeftButton:
  93                         b = mouse_button::button1;
  94                         break;
  95                 case Qt::MidButton:
  96                         b = mouse_button::button2;
  97                         break;
  98                 case Qt::RightButton:
  99                         b = mouse_button::button3;
 100                         break;
 101                 default:
 102                         break;
 103         }
 104         return b;
 105 }
 106
 107
 108 /// return the LyX mouse button state from Qt's
 109 mouse_button::state q_motion_state(Qt::MouseButtons state)
 110 {
 111         mouse_button::state b = mouse_button::none;
 112         if (state & Qt::LeftButton)
 113                 b |= mouse_button::button1;
 114         if (state & Qt::MidButton)
 115                 b |= mouse_button::button2;
 116         if (state & Qt::RightButton)
 117                 b |= mouse_button::button3;
 118         return b;
 119 }
 120
 121
 122 namespace frontend {
 123
 124 class CursorWidget {
 125 public:
 126         CursorWidget() {}
 127
 128         void draw(QPainter & painter)
 129         {
 130                 // FIXME: do something depending on the cursor shape.
 131                 if (show_ && rect_.isValid())
 132                         painter.fillRect(rect_, color_);
 133         }
 134
 135         void update(int x, int y, int h, CursorShape shape)
 136         {
 137                 color_ = guiApp->colorCache().get(Color::cursor);
 138                 rect_ = QRect(x, y, CursorWidth, h);
 139                 shape_ = shape;
 140         }
 141
 142         void show(bool set_show = true) { show_ = set_show; }
 143         void hide() { show_ = false; }
 144
 145         QRect const & rect() { return rect_; }
 146
 147 private:
 148         ///
 149         CursorShape shape_;
 150         ///
 151         bool show_;
 152         ///
 153         QColor color_;
 154         ///
 155         QRect rect_;
 156 };
 157
 158
 159 // This is a 'heartbeat' generating synthetic mouse move events when the
 160 // cursor is at the top or bottom edge of the viewport. One scroll per 0.2 s
 161 SyntheticMouseEvent::SyntheticMouseEvent()
 162         : timeout(200), restart_timeout(true),
 163           x_old(-1), y_old(-1), scrollbar_value_old(-1.0)
 164 {}
 165
 166
 167 GuiWorkArea::GuiWorkArea(int w, int h, int id, LyXView & lyx_view)
 168         : WorkArea(id, lyx_view), need_resize_(false), schedule_redraw_(false),
 169           preedit_lines_(1)
 170 {
 171         screen_ = QPixmap(viewport()->width(), viewport()->height());
 172         cursor_ = new frontend::CursorWidget();
 173         cursor_->hide();
 174
 175         setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
 176         setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 177         setAcceptDrops(true);
 178         setMouseTracking(true);
 179         setMinimumSize(100, 70);
 180
 181         viewport()->setAutoFillBackground(false);
 182         // We don't need double-buffering nor SystemBackground on
 183         // the viewport because we have our own backing pixmap.
 184         viewport()->setAttribute(Qt::WA_NoSystemBackground);
 185
 186         setFocusPolicy(Qt::WheelFocus);
 187
 188         viewport()->setCursor(Qt::IBeamCursor);
 189
 190         resize(w, h);
 191
 192         synthetic_mouse_event_.timeout.timeout.connect(
 193                 boost::bind(&GuiWorkArea::generateSyntheticMouseEvent,
 194                             this));
 195
 196         // Initialize the vertical Scroll Bar
 197         QObject::connect(verticalScrollBar(), SIGNAL(actionTriggered(int)),
 198                 this, SLOT(adjustViewWithScrollBar(int)));
 199
 200         // disable context menu for the scrollbar
 201         verticalScrollBar()->setContextMenuPolicy(Qt::NoContextMenu);
 202
 203         // PageStep only depends on the viewport height.
 204         verticalScrollBar()->setPageStep(viewport()->height());
 205
 206         LYXERR(Debug::GUI) << BOOST_CURRENT_FUNCTION
 207                 << "\n Area width\t" << width()
 208                 << "\n Area height\t" << height()
 209                 << "\n viewport width\t" << viewport()->width()
 210                 << "\n viewport height\t" << viewport()->height()
 211                 << endl;
 212
 213         // Enables input methods for asian languages.
 214         // Must be set when creating custom text editing widgets.
 215         setAttribute(Qt::WA_InputMethodEnabled, true);
 216 }
 217
 218
 219 void GuiWorkArea::setScrollbarParams(int h, int scroll_pos, int scroll_line_step)
 220 {
 221         if (verticalScrollBarPolicy() != Qt::ScrollBarAlwaysOn)
 222                 setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
 223
 224         verticalScrollBar()->setTracking(false);
 225
 226         // do what cursor movement does (some grey)
 227         h += height() / 4;
 228         int scroll_max_ = std::max(0, h - height());
 229
 230         verticalScrollBar()->setRange(0, scroll_max_);
 231         verticalScrollBar()->setSliderPosition(scroll_pos);
 232         verticalScrollBar()->setSingleStep(scroll_line_step);
 233         verticalScrollBar()->setValue(scroll_pos);
 234
 235         verticalScrollBar()->setTracking(true);
 236 }
 237
 238
 239 void GuiWorkArea::adjustViewWithScrollBar(int)
 240 {
 241         scrollBufferView(verticalScrollBar()->sliderPosition());
 242         QApplication::syncX();
 243 }
 244
 245
 246 void GuiWorkArea::dragEnterEvent(QDragEnterEvent * event)
 247 {
 248         if (event->mimeData()->hasUrls())
 249                 event->accept();
 250         /// \todo Ask lyx-devel is this is enough:
 251         /// if (event->mimeData()->hasFormat("text/plain"))
 252         ///     event->acceptProposedAction();
 253 }
 254
 255
 256 void GuiWorkArea::dropEvent(QDropEvent* event)
 257 {
 258         QList<QUrl> files = event->mimeData()->urls();
 259         if (files.isEmpty())
 260                 return;
 261
 262         LYXERR(Debug::GUI) << "GuiWorkArea::dropEvent: got URIs!" << endl;
 263         for (int i = 0; i!=files.size(); ++i) {
 264                 string const file = os::internal_path(fromqstr(files.at(i).toLocalFile()));
 265                 if (!file.empty())
 266                         dispatch(FuncRequest(LFUN_FILE_OPEN, file));
 267         }
 268 }
 269
 270
 271 void GuiWorkArea::focusInEvent(QFocusEvent * /*event*/)
 272 {
 273         // No need to do anything if we didn't change views...
 274 //      if (theApp() == 0 || &lyx_view_ == theApp()->currentView())
 275 //              return;
 276
 277         theApp()->setCurrentView(lyx_view_);
 278
 279         // Repaint the whole screen.
 280         // Note: this is different from redraw() as only the backing pixmap
 281         // will be redrawn, which is cheap.
 282         viewport()->repaint();
 283
 284         // FIXME: it would be better to send a signal "newBuffer()"
 285         // in BufferList that could be connected to the different tabbars.
 286         lyx_view_.updateTab();
 287
 288         startBlinkingCursor();
 289 }
 290
 291
 292 void GuiWorkArea::focusOutEvent(QFocusEvent * /*event*/)
 293 {
 294         stopBlinkingCursor();
 295 }
 296
 297
 298 void GuiWorkArea::mousePressEvent(QMouseEvent * e)
 299 {
 300         if (dc_event_.active && dc_event_ == *e) {
 301                 dc_event_.active = false;
 302                 FuncRequest cmd(LFUN_MOUSE_TRIPLE,
 303                         e->x(), e->y(),
 304                         q_button_state(e->button()));
 305                 dispatch(cmd);
 306                 return;
 307         }
 308
 309         inputContext()->reset();
 310
 311         FuncRequest const cmd(LFUN_MOUSE_PRESS, e->x(), e->y(),
 312                 q_button_state(e->button()));
 313         dispatch(cmd, q_key_state(e->modifiers()));
 314 }
 315
 316
 317 void GuiWorkArea::mouseReleaseEvent(QMouseEvent * e)
 318 {
 319         if (synthetic_mouse_event_.timeout.running())
 320                 synthetic_mouse_event_.timeout.stop();
 321
 322         FuncRequest const cmd(LFUN_MOUSE_RELEASE, e->x(), e->y(),
 323                               q_button_state(e->button()));
 324         dispatch(cmd);
 325 }
 326
 327
 328 void GuiWorkArea::mouseMoveEvent(QMouseEvent * e)
 329 {
 330         // we kill the triple click if we move
 331         doubleClickTimeout();
 332         FuncRequest cmd(LFUN_MOUSE_MOTION, e->x(), e->y(),
 333                               q_motion_state(e->buttons()));
 334
 335         // If we're above or below the work area...
 336         if (e->y() <= 20 || e->y() >= viewport()->height() - 20) {
 337                 // Make sure only a synthetic event can cause a page scroll,
 338                 // so they come at a steady rate:
 339                 if (e->y() <= 20)
 340                         // _Force_ a scroll up:
 341                         cmd.y = -40;
 342                 else
 343                         cmd.y = viewport()->height();
 344                 // Store the event, to be handled when the timeout expires.
 345                 synthetic_mouse_event_.cmd = cmd;
 346
 347                 if (synthetic_mouse_event_.timeout.running())
 348                         // Discard the event. Note that it _may_ be handled
 349                         // when the timeout expires if
 350                         // synthetic_mouse_event_.cmd has not been overwritten.
 351                         // Ie, when the timeout expires, we handle the
 352                         // most recent event but discard all others that
 353                         // occurred after the one used to start the timeout
 354                         // in the first place.
 355                         return;
 356                 else {
 357                         synthetic_mouse_event_.restart_timeout = true;
 358                         synthetic_mouse_event_.timeout.start();
 359                         // Fall through to handle this event...
 360                 }
 361
 362         } else if (synthetic_mouse_event_.timeout.running()) {
 363                 // Store the event, to be possibly handled when the timeout
 364                 // expires.
 365                 // Once the timeout has expired, normal control is returned
 366                 // to mouseMoveEvent (restart_timeout = false).
 367                 // This results in a much smoother 'feel' when moving the
 368                 // mouse back into the work area.
 369                 synthetic_mouse_event_.cmd = cmd;
 370                 synthetic_mouse_event_.restart_timeout = false;
 371                 return;
 372         }
 373
 374         // Has anything changed on-screen since the last QMouseEvent
 375         // was received?
 376         double const scrollbar_value = verticalScrollBar()->value();
 377         if (e->x() != synthetic_mouse_event_.x_old ||
 378             e->y() != synthetic_mouse_event_.y_old ||
 379             scrollbar_value != synthetic_mouse_event_.scrollbar_value_old) {
 380                 // Yes it has. Store the params used to check this.
 381                 synthetic_mouse_event_.x_old = e->x();
 382                 synthetic_mouse_event_.y_old = e->y();
 383                 synthetic_mouse_event_.scrollbar_value_old = scrollbar_value;
 384
 385                 // ... and dispatch the event to the LyX core.
 386                 dispatch(cmd);
 387         }
 388 }
 389
 390
 391 void GuiWorkArea::wheelEvent(QWheelEvent * e)
 392 {
 393         // Wheel rotation by one notch results in a delta() of 120 (see
 394         // documentation of QWheelEvent)
 395         int const lines = qApp->wheelScrollLines() * e->delta() / 120;
 396         verticalScrollBar()->setValue(verticalScrollBar()->value() -
 397                         lines *  verticalScrollBar()->singleStep());
 398         adjustViewWithScrollBar();
 399 }
 400
 401
 402 void GuiWorkArea::generateSyntheticMouseEvent()
 403 {
 404 // Set things off to generate the _next_ 'pseudo' event.
 405         if (synthetic_mouse_event_.restart_timeout)
 406                 synthetic_mouse_event_.timeout.start();
 407
 408         // Has anything changed on-screen since the last timeout signal
 409         // was received?
 410         double const scrollbar_value = verticalScrollBar()->value();
 411         if (scrollbar_value != synthetic_mouse_event_.scrollbar_value_old) {
 412                 // Yes it has. Store the params used to check this.
 413                 synthetic_mouse_event_.scrollbar_value_old = scrollbar_value;
 414
 415                 // ... and dispatch the event to the LyX core.
 416                 dispatch(synthetic_mouse_event_.cmd);
 417         }
 418 }
 419
 420
 421 void GuiWorkArea::keyPressEvent(QKeyEvent * e)
 422 {
 423         // do nothing if there are other events
 424         // (the auto repeated events come too fast)
 425         // \todo FIXME: remove hard coded Qt keys, process the key binding
 426 #ifdef Q_WS_X11
 427         if (XEventsQueued(QX11Info::display(), 0) > 1 && e->isAutoRepeat()
 428                         && (Qt::Key_PageDown || Qt::Key_PageUp)) {
 429                 LYXERR(Debug::KEY)
 430                         << BOOST_CURRENT_FUNCTION << endl
 431                         << "system is busy: scroll key event ignored" << endl;
 432                 e->ignore();
 433                 return;
 434         }
 435 #endif
 436
 437         LYXERR(Debug::KEY) << BOOST_CURRENT_FUNCTION
 438                 << " count=" << e->count()
 439                 << " text=" << fromqstr(e->text())
 440                 << " isAutoRepeat=" << e->isAutoRepeat()
 441                 << " key=" << e->key()
 442                 << endl;
 443
 444         boost::shared_ptr<QKeySymbol> sym(new QKeySymbol);
 445         sym->set(e);
 446         processKeySym(sym, q_key_state(e->modifiers()));
 447 }
 448
 449 void GuiWorkArea::doubleClickTimeout() {
 450         dc_event_.active = false;
 451 }
 452
 453 void GuiWorkArea::mouseDoubleClickEvent(QMouseEvent * e)
 454 {
 455         dc_event_ = double_click(e);
 456         QTimer::singleShot(QApplication::doubleClickInterval(), this,
 457                            SLOT(doubleClickTimeout()));
 458         FuncRequest cmd(LFUN_MOUSE_DOUBLE,
 459                         e->x(), e->y(),
 460                         q_button_state(e->button()));
 461         dispatch(cmd);
 462 }
 463
 464
 465 void GuiWorkArea::resizeEvent(QResizeEvent * ev)
 466 {
 467         QAbstractScrollArea::resizeEvent(ev);
 468         need_resize_ = true;
 469 }
 470
 471
 472 void GuiWorkArea::update(int x, int y, int w, int h)
 473 {
 474         viewport()->repaint(x, y, w, h);
 475 }
 476
 477
 478 void GuiWorkArea::doGreyOut(QLPainter & pain)
 479 {
 480         pain.fillRectangle(0, 0, width(), height(),
 481                 Color::bottomarea);
 482
 483         //if (!lyxrc.show_banner)
 484         //      return;
 485         LYXERR(Debug::GUI) << "show banner: " << lyxrc.show_banner << endl;
 486         /// The text to be written on top of the pixmap
 487         QString const text = lyx_version ? QString(lyx_version) : qt_("unknown version");
 488         FileName const file = support::libFileSearch("images", "banner", "png");
 489         if (file.empty())
 490                 return;
 491
 492         QPixmap pm(toqstr(file.absFilename()));
 493         if (!pm) {
 494                 lyxerr << "could not load splash screen: '" << file << "'" << endl;
 495                 return;
 496         }
 497
 498         QFont font;
 499         // The font used to display the version info
 500         font.setStyleHint(QFont::SansSerif);
 501         font.setWeight(QFont::Bold);
 502         font.setPointSize(convert<int>(lyxrc.font_sizes[Font::SIZE_LARGE]));
 503
 504         int const w = pm.width();
 505         int const h = pm.height();
 506
 507         int x = (width() - w) / 2;
 508         int y = (height() - h) / 2;
 509
 510         pain.drawPixmap(x, y, pm);
 511
 512         x += 260;
 513         y += 270;
 514
 515         pain.setPen(QColor(255, 255, 0));
 516         pain.setFont(font);
 517         pain.drawText(x, y, text);
 518 }
 519
 520
 521 void GuiWorkArea::paintEvent(QPaintEvent * ev)
 522 {
 523         QRect const rc = ev->rect();
 524         /*
 525         LYXERR(Debug::PAINTING) << "paintEvent begin: x: " << rc.x()
 526                 << " y: " << rc.y()
 527                 << " w: " << rc.width()
 528                 << " h: " << rc.height() << endl;
 529         */
 530
 531         if (need_resize_) {
 532                 verticalScrollBar()->setPageStep(viewport()->height());
 533                 screen_ = QPixmap(viewport()->width(), viewport()->height());
 534                 resizeBufferView();
 535                 updateScreen();
 536                 need_resize_ = false;
 537         }
 538
 539         QPainter pain(viewport());
 540         pain.drawPixmap(rc, screen_, rc);
 541         cursor_->draw(pain);
 542 }
 543
 544
 545 void GuiWorkArea::expose(int x, int y, int w, int h)
 546 {
 547         updateScreen();
 548         update(x, y, w, h);
 549 }
 550
 551
 552 void GuiWorkArea::updateScreen()
 553 {
 554         QLPainter pain(&screen_);
 555
 556         if (greyed_out_) {
 557                 LYXERR(Debug::GUI) << "splash screen requested" << endl;
 558                 verticalScrollBar()->hide();
 559                 doGreyOut(pain);
 560                 return;
 561         }
 562
 563         verticalScrollBar()->show();
 564         paintText(*buffer_view_, pain);
 565 }
 566
 567
 568 void GuiWorkArea::showCursor(int x, int y, int h, CursorShape shape)
 569 {
 570         if (schedule_redraw_) {
 571                 if (buffer_view_ && buffer_view_->buffer()) {
 572                         buffer_view_->update(Update::Force);
 573                         updateScreen();
 574                         viewport()->update(QRect(0, 0, viewport()->width(), viewport()->height()));
 575                 }
 576                 schedule_redraw_ = false;
 577                 // Show the cursor immediately after the update.
 578                 hideCursor();
 579                 toggleCursor();
 580                 return;
 581         }
 582
 583         cursor_->update(x, y, h, shape);
 584         cursor_->show();
 585         viewport()->update(cursor_->rect());
 586 }
 587
 588
 589 void GuiWorkArea::removeCursor()
 590 {
 591         cursor_->hide();
 592         //if (!qApp->focusWidget())
 593                 viewport()->update(cursor_->rect());
 594 }
 595
 596
 597 void GuiWorkArea::inputMethodEvent(QInputMethodEvent * e)
 598 {
 599         QString const & commit_string = e->commitString();
 600         docstring const & preedit_string
 601                 = qstring_to_ucs4(e->preeditString());
 602
 603         if(greyed_out_) {
 604                 e->ignore();
 605                 return;
 606         }
 607
 608         if (!commit_string.isEmpty()) {
 609
 610                 LYXERR(Debug::KEY) << BOOST_CURRENT_FUNCTION
 611                         << " preeditString =" << fromqstr(e->preeditString())
 612                         << " commitString  =" << fromqstr(e->commitString())
 613                         << endl;
 614
 615                 int key = 0;
 616
 617                 // FIXME Iwami 04/01/07: we should take care also of UTF16 surrogates here.
 618                 for (int i = 0; i < commit_string.size(); ++i) {
 619                         QKeyEvent ev(QEvent::KeyPress, key, Qt::NoModifier, commit_string[i]);
 620                         keyPressEvent(&ev);
 621                 }
 622         }
 623
 624         // Hide the cursor during the kana-kanji transformation.
 625         if (preedit_string.empty())
 626                 startBlinkingCursor();
 627         else
 628                 stopBlinkingCursor();
 629
 630         // last_width : for checking if last preedit string was/wasn't empty.
 631         static bool last_width = false;
 632         if (!last_width && preedit_string.empty()) {
 633                 // if last_width is last length of preedit string.
 634                 e->accept();
 635                 return;
 636         }
 637
 638         QLPainter pain(&screen_);
 639         buffer_view_->updateMetrics(false);
 640         paintText(*buffer_view_, pain);
 641         Font font = buffer_view_->cursor().getFont();
 642         FontMetrics const & fm = theFontMetrics(font);
 643         int height = fm.maxHeight();
 644         int cur_x = cursor_->rect().left();
 645         int cur_y = cursor_->rect().bottom();
 646
 647         // redraw area of preedit string.
 648         update(0, cur_y - height, GuiWorkArea::width(),
 649                 (height + 1) * preedit_lines_);
 650
 651         if (preedit_string.empty()) {
 652                 last_width = false;
 653                 preedit_lines_ = 1;
 654                 e->accept();
 655                 return;
 656         }
 657         last_width = true;
 658
 659         // att : stores an IM attribute.
 660         QList<QInputMethodEvent::Attribute> const & att = e->attributes();
 661
 662         // get attributes of input method cursor.
 663         // cursor_pos : cursor position in preedit string.
 664         size_t cursor_pos = 0;
 665         bool cursor_is_visible = false;
 666         for (int i = 0; i < att.size(); ++i) {
 667                 if (att.at(i).type == QInputMethodEvent::Cursor) {
 668                         cursor_pos = att.at(i).start;
 669                         cursor_is_visible = att.at(i).length != 0;
 670                         break;
 671                 }
 672         }
 673
 674         size_t preedit_length = preedit_string.length();
 675
 676         // get position of selection in input method.
 677         // FIXME: isn't there a way to do this simplier?
 678         // rStart : cursor position in selected string in IM.
 679         size_t rStart = 0;
 680         // rLength : selected string length in IM.
 681         size_t rLength = 0;
 682         if (cursor_pos < preedit_length) {
 683                 for (int i = 0; i < att.size(); ++i) {
 684                         if (att.at(i).type == QInputMethodEvent::TextFormat) {
 685                                 if (att.at(i).start <= int(cursor_pos)
 686                                         && int(cursor_pos) < att.at(i).start + att.at(i).length) {
 687                                                 rStart = att.at(i).start;
 688                                                 rLength = att.at(i).length;
 689                                                 if (!cursor_is_visible)
 690                                                         cursor_pos += rLength;
 691                                                 break;
 692                                 }
 693                         }
 694                 }
 695         }
 696         else {
 697                 rStart = cursor_pos;
 698                 rLength = 0;
 699         }
 700
 701         int const right_margin = rightMargin();
 702         Painter::preedit_style ps;
 703         // Most often there would be only one line:
 704         preedit_lines_ = 1;
 705         for (size_t pos = 0; pos != preedit_length; ++pos) {
 706                 char_type const typed_char = preedit_string[pos];
 707                 // reset preedit string style
 708                 ps = Painter::preedit_default;
 709
 710                 // if we reached the right extremity of the screen, go to next line.
 711                 if (cur_x + fm.width(typed_char) > GuiWorkArea::width() - right_margin) {
 712                         cur_x = right_margin;
 713                         cur_y += height + 1;
 714                         ++preedit_lines_;
 715                 }
 716                 // preedit strings are displayed with dashed underline
 717                 // and partial strings are displayed white on black indicating
 718                 // that we are in selecting mode in the input method.
 719                 // FIXME: rLength == preedit_length is not a changing condition
 720                 // FIXME: should be put out of the loop.
 721                 if (pos >= rStart
 722                         && pos < rStart + rLength
 723                         && !(cursor_pos < rLength && rLength == preedit_length))
 724                         ps = Painter::preedit_selecting;
 725
 726                 if (pos == cursor_pos
 727                         && (cursor_pos < rLength && rLength == preedit_length))
 728                         ps = Painter::preedit_cursor;
 729
 730                 // draw one character and update cur_x.
 731                 cur_x += pain.preeditText(cur_x, cur_y, typed_char, font, ps);
 732         }
 733
 734         // update the preedit string screen area.
 735         update(0, cur_y - preedit_lines_*height, GuiWorkArea::width(),
 736                 (height + 1) * preedit_lines_);
 737
 738         // Don't forget to accept the event!
 739         e->accept();
 740 }
 741
 742
 743 QVariant GuiWorkArea::inputMethodQuery(Qt::InputMethodQuery query) const
 744 {
 745         QRect cur_r(0,0,0,0);
 746         switch (query) {
 747                 // this is the CJK-specific composition window position.
 748                 case Qt::ImMicroFocus:
 749                         cur_r = cursor_->rect();
 750                         if (preedit_lines_ != 1)
 751                                 cur_r.moveLeft(10);
 752                         cur_r.moveBottom(cur_r.bottom() + cur_r.height() * preedit_lines_);
 753                         // return lower right of cursor in LyX.
 754                         return cur_r;
 755                 default:
 756                         return QWidget::inputMethodQuery(query);
 757         }
 758 }
 759
 760 } // namespace frontend
 761 } // namespace lyx
 762
 763 #include "GuiWorkArea_moc.cpp"