Qt-5는 자신을 구현할 때 유용한 참조 일 수있는 example of an elided label class을 포함합니다. 이 예에서
:
elidedlabel.h :
class ElidedLabel : public QFrame
{
Q_OBJECT
Q_PROPERTY(QString text READ text WRITE setText)
Q_PROPERTY(bool isElided READ isElided)
public:
explicit ElidedLabel(const QString &text, QWidget *parent = 0);
void setText(const QString &text);
const QString & text() const { return content; }
bool isElided() const { return elided; }
protected:
void paintEvent(QPaintEvent *event) Q_DECL_OVERRIDE;
signals:
void elisionChanged(bool elided);
private:
bool elided;
QString content;
};
elidedlabel.cpp :
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;
//! [2]
//! [3]
} 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);
}
}
또한'minimumSizeHint()'같은 뭔가 재 구현 고려'QSize (0을 반환, QLabel :: minimumSizeHint(). height());'. 그렇지 않으면 원래 텍스트 너비 아래에서 레이블의 크기를 조정할 수 없습니다. – kaveish