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# elidedlabel.cpp Example File

widgets/elidedlabel/elidedlabel.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
     ** Contact: http://www.qt-project.org/legal
     **
     ** This file is part of the QtCore module of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
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     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
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     **     of its contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
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     #include "elidedlabel.h"

     #include <QPainter>
     #include <QTextLayout>
     #include <QDebug>

     ElidedLabel::ElidedLabel(const QString &text, QWidget *parent)
         : QFrame(parent)
         , elided(false)
         , content(text)
     {
         setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
     }

     void ElidedLabel::setText(const QString &newText)
     {
         content = newText;
         update();
     }

     void ElidedLabel::paintEvent(QPaintEvent *event)
     {
         QFrame::paintEvent(event);

         QPainter painter(this);
         QFontMetrics fontMetrics = painter.fontMetrics();

         bool didElide = false;
         int lineSpacing = fontMetrics.lineSpacing();
         int y = 0;

         QTextLayout textLayout(content, painter.font());
         textLayout.beginLayout();
         forever {
             QTextLine line = textLayout.createLine();

             if (!line.isValid())
                 break;

             line.setLineWidth(width());
             int nextLineY = y + lineSpacing;

             if (height() >= nextLineY + lineSpacing) {
                 line.draw(&painter, QPoint(0, y));
                 y = nextLineY;
             } else {
                 QString lastLine = content.mid(line.textStart());
                 QString elidedLastLine = fontMetrics.elidedText(lastLine, Qt::ElideRight, width());
                 painter.drawText(QPoint(0, y + fontMetrics.ascent()), elidedLastLine);
                 line = textLayout.createLine();
                 didElide = line.isValid();
                 break;
             }
         }
         textLayout.endLayout();

         if (didElide != elided) {
             elided = didElide;
             emit elisionChanged(didElide);
         }
     }