* Copyright (C) 2007 Jani Huhtanen <jani.huhtanen@tut.fi> *
* Copyright (C) 2007 by Robert Knight <robertknight@gmail.com> *
* Copyright (C) 2008 by Alexis Ménard <darktears31@gmail.com> *
* Copyright (C) 2008 by Marco Martin <notmart@gmail.com> *
* Copyright (C) 2012-2013 by Eike Hein <hein@kde.org> *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the *
* Free Software Foundation, Inc., *
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA . *
***************************************************************************/
#include "textlabel.h"
#include "blur.cpp"
#include <QApplication>
#include <QPainter>
#include <QStyle>
TextLabel::TextLabel(QQuickItem* parent) : QQuickPaintedItem(parent),
m_enabled(true),
m_elide(false)
{
}
TextLabel::~TextLabel()
{
}
bool TextLabel::enabled() const
{
return m_enabled;
}
void TextLabel::setEnabled(bool enabled)
{
if (enabled != m_enabled) {
m_enabled = enabled;
update();
}
}
QString TextLabel::text() const
{
return m_text;
}
void TextLabel::setText(const QString& text)
{
if (text != m_text)
{
m_text = text;
m_cachedShadow = QPixmap();
updateImplicitSize();
update();
emit textChanged(text);
}
}
QColor TextLabel::color() const
{
return m_color;
}
void TextLabel::setColor(const QColor& color)
{
if (color != m_color)
{
m_color = color;
m_cachedShadow = QPixmap();
update();
}
}
bool TextLabel::elide() const
{
return m_elide;
}
void TextLabel::setElide(bool elide)
{
m_elide = elide;
updateImplicitSize();
}
void TextLabel::updateImplicitSize()
{
if (m_elide) {
setImplicitWidth(0);
setImplicitHeight(0);
} else {
QFontMetrics fm(QFontDatabase::systemFont(QFontDatabase::GeneralFont));
setImplicitWidth(fm.width(m_text));
setImplicitHeight(fm.height());
}
}
void TextLabel::geometryChanged(const QRectF& newGeometry, const QRectF& oldGeometry)
{
if (newGeometry.size() != oldGeometry.size()) {
m_cachedShadow = QPixmap();
}
}
QColor TextLabel::textColor() const
{
QColor color(m_color);
if (!m_enabled) {
color.setAlphaF(0.5);
}
return color;
}
QTextOption TextLabel::textOption() const
{
Qt::LayoutDirection direction = QApplication::layoutDirection();
Qt::Alignment alignment = QStyle::visualAlignment(direction, Qt::AlignLeft | Qt::AlignVCenter);
QTextOption option;
option.setTextDirection(direction);
option.setAlignment(alignment);
return option;
}
void TextLabel::layoutText(QTextLayout &layout, const QString &text, const QSize &constraints)
{
QFontMetrics metrics(layout.font());
int leading = metrics.leading();
int height = 0;
int maxWidth = constraints.width();
int widthUsed = 0;
int lineSpacing = metrics.lineSpacing();
QTextLine line;
layout.setText(text);
layout.beginLayout();
while ((line = layout.createLine()).isValid()) {
height += leading;
if (height + 2 * lineSpacing > constraints.height()) {
line.setPosition(QPoint(0, height));
break;
}
line.setLineWidth(maxWidth);
line.setPosition(QPoint(0, height));
height += int(line.height());
widthUsed = int(qMax(qreal(widthUsed), line.naturalTextWidth()));
}
layout.endLayout();
}
void TextLabel::drawTextLayout(QPainter *painter, const QTextLayout &layout, const QRect &rect)
{
if (rect.width() < 1 || rect.height() < 1) {
return;
}
QPixmap pixmap(rect.size());
pixmap.fill(Qt::transparent);
QPainter p(&pixmap);
p.setPen(painter->pen());
QLinearGradient alphaGradient(0, 0, 1, 0);
alphaGradient.setCoordinateMode(QGradient::ObjectBoundingMode);
if (layout.textOption().textDirection() == Qt::LeftToRight) {
alphaGradient.setColorAt(0, QColor(0, 0, 0, 255));
alphaGradient.setColorAt(1, QColor(0, 0, 0, 0));
} else {
alphaGradient.setColorAt(0, QColor(0, 0, 0, 0));
alphaGradient.setColorAt(1, QColor(0, 0, 0, 255));
}
QFontMetrics fm(layout.font());
int textHeight = layout.lineCount() * fm.lineSpacing();
QPointF position(0, (rect.height() - textHeight) / 2);
QList<QRect> fadeRects;
int fadeWidth = 30;
for (int i = 0; i < layout.lineCount(); i++) {
QTextLine line = layout.lineAt(i);
line.draw(&p, position);
if (line.naturalTextWidth() > rect.width())
{
int x = int(qMin(line.naturalTextWidth(), (qreal)pixmap.width())) - fadeWidth;
int y = int(line.position().y() + position.y());
QRect r = QStyle::visualRect(layout.textOption().textDirection(), pixmap.rect(),
QRect(x, y, fadeWidth, int(line.height())));
fadeRects.append(r);
}
}
if (!fadeRects.isEmpty()) {
p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
foreach (const QRect &rect, fadeRects) {
p.fillRect(rect, alphaGradient);
}
}
p.end();
QColor shadowColor;
if (qGray(textColor().rgb()) > 192) {
shadowColor = Qt::black;
} else {
shadowColor = Qt::white;
}
if (m_cachedShadow.isNull()) {
QImage shadow = pixmap.toImage();
expblur<16, 7>(shadow, 1);
QPainter p(&shadow);
p.setCompositionMode(QPainter::CompositionMode_SourceIn);
p.fillRect(shadow.rect(), shadowColor);
p.end();
m_cachedShadow = QPixmap(shadow.size());
m_cachedShadow.fill(Qt::transparent);
QPainter buffPainter(&m_cachedShadow);
buffPainter.drawImage(QPoint(0,0), shadow);
}
if (shadowColor == Qt::white) {
painter->drawPixmap(rect.topLeft(), m_cachedShadow);
} else {
painter->drawPixmap(rect.topLeft() + QPoint(1, 2), m_cachedShadow);
}
painter->drawPixmap(rect.topLeft(), pixmap);
}
void TextLabel::paint(QPainter* painter)
{
painter->setPen(QPen(textColor(), 1.0));
if (QFontDatabase::systemFont(QFontDatabase::GeneralFont) != m_layout.font()) {
m_cachedShadow = QPixmap();
}
QFont font = QFontDatabase::systemFont(QFontDatabase::GeneralFont);
QFontMetrics fm(QFontDatabase::systemFont(QFontDatabase::GeneralFont));
if (fm.tightBoundingRect(QLatin1String("M")).height() > boundingRect().toRect().height()) {
font.setPixelSize(boundingRect().toRect().height());
}
m_layout.setFont(font);
m_layout.setTextOption(textOption());
layoutText(m_layout, text(), boundingRect().toRect().size());
drawTextLayout(painter, m_layout, boundingRect().toRect());
}
