elidedlabel.cpp Example File

widgets/elidedlabel/elidedlabel.cpp
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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); } }