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50 | |
51 | #include "elidedlabel.h" |
52 | |
53 | #include <QPainter> |
54 | #include <QSizePolicy> |
55 | #include <QTextLayout> |
56 | |
57 | //! [0] |
58 | ElidedLabel::ElidedLabel(const QString &text, QWidget *parent) |
59 | : QFrame(parent) |
60 | , elided(false) |
61 | , content(text) |
62 | { |
63 | setSizePolicy(hor: QSizePolicy::Expanding, ver: QSizePolicy::Preferred); |
64 | } |
65 | //! [0] |
66 | |
67 | //! [1] |
68 | void ElidedLabel::setText(const QString &newText) |
69 | { |
70 | content = newText; |
71 | update(); |
72 | } |
73 | //! [1] |
74 | |
75 | //! [2] |
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(p: &painter, point: QPoint(0, y)); |
100 | y = nextLineY; |
101 | //! [2] |
102 | //! [3] |
103 | } else { |
104 | QString lastLine = content.mid(position: line.textStart()); |
105 | QString elidedLastLine = fontMetrics.elidedText(text: lastLine, mode: Qt::ElideRight, width: width()); |
106 | painter.drawText(p: QPoint(0, y + fontMetrics.ascent()), s: 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(elided: didElide); |
119 | } |
120 | } |
121 | //! [4] |
122 | |