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50
51 #include "elidedlabel.h"
52
53 #include <QPainter>
54 #include <QSizePolicy>
55 #include <QTextLayout>
56
57 //! [0]
ElidedLabel(const QString & text,QWidget * parent)58 ElidedLabel::ElidedLabel(const QString &text, QWidget *parent)
59 : QFrame(parent)
60 , elided(false)
61 , content(text)
62 {
63 setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
64 }
65 //! [0]
66
67 //! [1]
setText(const QString & newText)68 void ElidedLabel::setText(const QString &newText)
69 {
70 content = newText;
71 update();
72 }
73 //! [1]
74
75 //! [2]
paintEvent(QPaintEvent * event)76 void ElidedLabel::paintEvent(QPaintEvent *event)
77 {
78 QFrame::paintEvent(event);
79
80 QPainter painter(this);
81 QFontMetrics fontMetrics = painter.fontMetrics();
82
83 bool didElide = false;
84 int lineSpacing = fontMetrics.lineSpacing();
85 int y = 0;
86
87 QTextLayout textLayout(content, painter.font());
88 textLayout.beginLayout();
89 forever {
90 QTextLine line = textLayout.createLine();
91
92 if (!line.isValid())
93 break;
94
95 line.setLineWidth(width());
96 int nextLineY = y + lineSpacing;
97
98 if (height() >= nextLineY + lineSpacing) {
99 line.draw(&painter, QPoint(0, y));
100 y = nextLineY;
101 //! [2]
102 //! [3]
103 } else {
104 QString lastLine = content.mid(line.textStart());
105 QString elidedLastLine = fontMetrics.elidedText(lastLine, Qt::ElideRight, width());
106 painter.drawText(QPoint(0, y + fontMetrics.ascent()), elidedLastLine);
107 line = textLayout.createLine();
108 didElide = line.isValid();
109 break;
110 }
111 }
112 textLayout.endLayout();
113 //! [3]
114
115 //! [4]
116 if (didElide != elided) {
117 elided = didElide;
118 emit elisionChanged(didElide);
119 }
120 }
121 //! [4]
122