src/gui/widgets/qprogressbar.cpp
changeset 0 1918ee327afb
child 4 3b1da2848fc7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gui/widgets/qprogressbar.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,595 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qprogressbar.h"
+#ifndef QT_NO_PROGRESSBAR
+#include <qevent.h>
+#include <qpainter.h>
+#include <qstylepainter.h>
+#include <qstyleoption.h>
+#include <private/qwidget_p.h>
+#ifndef QT_NO_ACCESSIBILITY
+#include <qaccessible.h>
+#endif
+#include <limits.h>
+
+QT_BEGIN_NAMESPACE
+
+class QProgressBarPrivate : public QWidgetPrivate
+{
+    Q_DECLARE_PUBLIC(QProgressBar)
+
+public:
+    QProgressBarPrivate();
+
+    void init();
+    inline void resetLayoutItemMargins();
+
+    int minimum;
+    int maximum;
+    int value;
+    Qt::Alignment alignment;
+    uint textVisible : 1;
+    int lastPaintedValue;
+    Qt::Orientation orientation;
+    bool invertedAppearance;
+    QProgressBar::Direction textDirection;
+    QString format;
+    inline int bound(int val) const { return qMax(minimum-1, qMin(maximum, val)); }
+    bool repaintRequired() const;
+};
+
+QProgressBarPrivate::QProgressBarPrivate()
+    : minimum(0), maximum(100), value(-1), alignment(Qt::AlignLeft), textVisible(true),
+      lastPaintedValue(-1), orientation(Qt::Horizontal), invertedAppearance(false),
+      textDirection(QProgressBar::TopToBottom), format(QLatin1String("%p%"))
+{
+}
+
+void QProgressBarPrivate::init()
+{
+    Q_Q(QProgressBar);
+    QSizePolicy sp(QSizePolicy::Expanding, QSizePolicy::Fixed);
+    if (orientation == Qt::Vertical)
+        sp.transpose();
+    q->setSizePolicy(sp);
+    q->setAttribute(Qt::WA_WState_OwnSizePolicy, false);
+    resetLayoutItemMargins();
+}
+
+void QProgressBarPrivate::resetLayoutItemMargins()
+{
+    Q_Q(QProgressBar);
+    QStyleOptionProgressBar option;
+    q->initStyleOption(&option);
+    setLayoutItemMargins(QStyle::SE_ProgressBarLayoutItem, &option);
+}
+
+/*!
+    Initialize \a option with the values from this QProgressBar. This method is useful
+    for subclasses when they need a QStyleOptionProgressBar or QStyleOptionProgressBarV2,
+    but don't want to fill in all the information themselves. This function will check the version
+    of the QStyleOptionProgressBar and fill in the additional values for a
+    QStyleOptionProgressBarV2.
+
+    \sa QStyleOption::initFrom()
+*/
+void QProgressBar::initStyleOption(QStyleOptionProgressBar *option) const
+{
+    if (!option)
+        return;
+    Q_D(const QProgressBar);
+    option->initFrom(this);
+
+    if (d->orientation == Qt::Horizontal)
+        option->state |= QStyle::State_Horizontal;
+    option->minimum = d->minimum;
+    option->maximum = d->maximum;
+    option->progress = d->value;
+    option->textAlignment = d->alignment;
+    option->textVisible = d->textVisible;
+    option->text = text();
+
+    if (QStyleOptionProgressBarV2 *optionV2
+            = qstyleoption_cast<QStyleOptionProgressBarV2 *>(option)) {
+        optionV2->orientation = d->orientation;  // ### Qt 5: use State_Horizontal instead
+        optionV2->invertedAppearance = d->invertedAppearance;
+        optionV2->bottomToTop = (d->textDirection == QProgressBar::BottomToTop);
+    }
+}
+
+bool QProgressBarPrivate::repaintRequired() const
+{
+    Q_Q(const QProgressBar);
+    if (value == lastPaintedValue)
+        return false;
+
+    int valueDifference = qAbs(value - lastPaintedValue);
+
+    // Check if the text needs to be repainted
+    if (value == minimum || value == maximum)
+        return true;
+    if (textVisible) {
+        if ((format.contains(QLatin1String("%v"))))
+            return true;
+        if ((format.contains(QLatin1String("%p"))
+             && valueDifference >= qAbs((maximum - minimum) / 100)))
+            return true;
+    }
+
+    // Check if the bar needs to be repainted
+    QStyleOptionProgressBarV2 opt;
+    q->initStyleOption(&opt);
+    int cw = q->style()->pixelMetric(QStyle::PM_ProgressBarChunkWidth, &opt, q);
+    QRect groove  = q->style()->subElementRect(QStyle::SE_ProgressBarGroove, &opt, q);
+    // This expression is basically
+    // (valueDifference / (maximum - minimum) > cw / groove.width())
+    // transformed to avoid integer division.
+    int grooveBlock = (q->orientation() == Qt::Horizontal) ? groove.width() : groove.height();
+    return (valueDifference * grooveBlock > cw * (maximum - minimum));
+}
+
+/*!
+    \class QProgressBar
+    \brief The QProgressBar widget provides a horizontal or vertical progress bar.
+
+    \ingroup basicwidgets
+
+
+    A progress bar is used to give the user an indication of the
+    progress of an operation and to reassure them that the application
+    is still running.
+
+    The progress bar uses the concept of \e steps. You set it up by
+    specifying the minimum and maximum possible step values, and it
+    will display the percentage of steps that have been completed
+    when you later give it the current step value. The percentage is
+    calculated by dividing the progress (value() - minimum()) divided
+    by maximum() - minimum().
+
+    You can specify the minimum and maximum number of steps with
+    setMinimum() and setMaximum. The current number of steps is set
+    with setValue(). The progress bar can be rewound to the
+    beginning with reset().
+
+    If minimum and maximum both are set to 0, the bar shows a busy
+    indicator instead of a percentage of steps. This is useful, for
+    example, when using QFtp or QNetworkAccessManager to download
+    items when they are unable to determine the size of the item being
+    downloaded.
+
+    \table
+    \row \o \inlineimage macintosh-progressbar.png Screenshot of a Macintosh style progress bar
+         \o A progress bar shown in the Macintosh widget style.
+    \row \o \inlineimage windowsxp-progressbar.png Screenshot of a Windows XP style progress bar
+         \o A progress bar shown in the Windows XP widget style.
+    \row \o \inlineimage plastique-progressbar.png Screenshot of a Plastique style progress bar
+         \o A progress bar shown in the Plastique widget style.
+    \endtable
+
+    \sa QProgressDialog, {fowler}{GUI Design Handbook: Progress Indicator}
+*/
+
+/*!
+    \since 4.1
+    \enum QProgressBar::Direction
+    \brief Specifies the reading direction of the \l text for vertical progress bars.
+
+    \value TopToBottom The text is rotated 90 degrees clockwise.
+    \value BottomToTop The text is rotated 90 degrees counter-clockwise.
+
+    Note that whether or not the text is drawn is dependent on the style.
+    Currently CDE, CleanLooks, Motif, and Plastique draw the text. Mac, Windows
+    and WindowsXP style do not.
+
+    \sa textDirection
+*/
+
+/*!
+    \fn void QProgressBar::valueChanged(int value)
+
+    This signal is emitted when the value shown in the progress bar changes.
+    \a value is the new value shown by the progress bar.
+*/
+
+/*!
+    Constructs a progress bar with the given \a parent.
+
+    By default, the minimum step value is set to 0, and the maximum to 100.
+
+    \sa setRange()
+*/
+
+QProgressBar::QProgressBar(QWidget *parent)
+    : QWidget(*(new QProgressBarPrivate), parent, 0)
+{
+    d_func()->init();
+}
+
+/*!
+    Reset the progress bar. The progress bar "rewinds" and shows no
+    progress.
+*/
+
+void QProgressBar::reset()
+{
+    Q_D(QProgressBar);
+    d->value = d->minimum - 1;
+    if (d->minimum == INT_MIN)
+        d->value = INT_MIN;
+    repaint();
+}
+
+/*!
+    \property QProgressBar::minimum
+    \brief the progress bar's minimum value
+
+    When setting this property, the \l maximum is adjusted if
+    necessary to ensure that the range remains valid. If the
+    current value falls outside the new range, the progress bar is reset
+    with reset().
+*/
+void QProgressBar::setMinimum(int minimum)
+{
+    setRange(minimum, qMax(d_func()->maximum, minimum));
+}
+
+int QProgressBar::minimum() const
+{
+    return d_func()->minimum;
+}
+
+
+/*!
+    \property QProgressBar::maximum
+    \brief the progress bar's maximum value
+
+    When setting this property, the \l minimum is adjusted if
+    necessary to ensure that the range remains valid. If the
+    current value falls outside the new range, the progress bar is reset
+    with reset().
+*/
+
+void QProgressBar::setMaximum(int maximum)
+{
+    setRange(qMin(d_func()->minimum, maximum), maximum);
+}
+
+int QProgressBar::maximum() const
+{
+    return d_func()->maximum;
+}
+
+/*!
+    \property QProgressBar::value
+    \brief the progress bar's current value
+
+    Attempting to change the current value to one outside
+    the minimum-maximum range has no effect on the current value.
+*/
+void QProgressBar::setValue(int value)
+{
+    Q_D(QProgressBar);
+    if (d->value == value
+            || ((value > d->maximum || value < d->minimum)
+                && (d->maximum != 0 || d->minimum != 0)))
+        return;
+    d->value = value;
+    emit valueChanged(value);
+#ifndef QT_NO_ACCESSIBILITY
+    QAccessible::updateAccessibility(this, 0, QAccessible::ValueChanged);
+#endif
+    if (d->repaintRequired())
+        repaint();
+}
+
+int QProgressBar::value() const
+{
+    return d_func()->value;
+}
+
+/*!
+    Sets the progress bar's minimum and maximum values to \a minimum and
+    \a maximum respectively.
+
+    If \a maximum is smaller than \a minimum, \a minimum becomes the only
+    legal value.
+
+    If the current value falls outside the new range, the progress bar is reset
+    with reset().
+
+    \sa minimum maximum
+*/
+void QProgressBar::setRange(int minimum, int maximum)
+{
+    Q_D(QProgressBar);
+    d->minimum = minimum;
+    d->maximum = qMax(minimum, maximum);
+    if ( d->value <(d->minimum-1) || d->value > d->maximum)
+        reset();
+}
+/*!
+    \property QProgressBar::textVisible
+    \brief whether the current completed percentage should be displayed
+
+    This property may be ignored by the style (e.g., QMacStyle never draws the text).
+
+    \sa textDirection
+*/
+void QProgressBar::setTextVisible(bool visible)
+{
+    Q_D(QProgressBar);
+    if (d->textVisible != visible) {
+        d->textVisible = visible;
+        repaint();
+    }
+}
+
+bool QProgressBar::isTextVisible() const
+{
+    return d_func()->textVisible;
+}
+
+/*!
+    \property QProgressBar::alignment
+    \brief the alignment of the progress bar
+*/
+void QProgressBar::setAlignment(Qt::Alignment alignment)
+{
+    if (d_func()->alignment != alignment) {
+        d_func()->alignment = alignment;
+        repaint();
+    }
+}
+
+Qt::Alignment QProgressBar::alignment() const
+{
+    return d_func()->alignment;
+}
+
+/*!
+    \reimp
+*/
+void QProgressBar::paintEvent(QPaintEvent *)
+{
+    QStylePainter paint(this);
+    QStyleOptionProgressBarV2 opt;
+    initStyleOption(&opt);
+    paint.drawControl(QStyle::CE_ProgressBar, opt);
+    d_func()->lastPaintedValue = d_func()->value;
+}
+
+/*!
+    \reimp
+*/
+QSize QProgressBar::sizeHint() const
+{
+    ensurePolished();
+    QFontMetrics fm = fontMetrics();
+    QStyleOptionProgressBarV2 opt;
+    initStyleOption(&opt);
+    int cw = style()->pixelMetric(QStyle::PM_ProgressBarChunkWidth, &opt, this);
+    QSize size = QSize(qMax(9, cw) * 7 + fm.width(QLatin1Char('0')) * 4, fm.height() + 8);
+    if (opt.orientation == Qt::Vertical)
+        size.transpose();
+    return style()->sizeFromContents(QStyle::CT_ProgressBar, &opt, size, this);
+}
+
+/*!
+    \reimp
+*/
+QSize QProgressBar::minimumSizeHint() const
+{
+    QSize size;
+    if (orientation() == Qt::Horizontal)
+        size = QSize(sizeHint().width(), fontMetrics().height() + 2);
+    else
+        size = QSize(fontMetrics().height() + 2, sizeHint().height());
+    return size;
+}
+
+/*!
+    \property QProgressBar::text
+    \brief the descriptive text shown with the progress bar
+
+    The text returned is the same as the text displayed in the center
+    (or in some styles, to the left) of the progress bar.
+
+    The progress shown in the text may be smaller than the minimum value,
+    indicating that the progress bar is in the "reset" state before any
+    progress is set.
+
+    In the default implementation, the text either contains a percentage
+    value that indicates the progress so far, or it is blank because the
+    progress bar is in the reset state.
+*/
+QString QProgressBar::text() const
+{
+    Q_D(const QProgressBar);
+    if ((d->maximum == 0 && d->minimum == 0) || d->value < d->minimum
+            || (d->value == INT_MIN && d->minimum == INT_MIN))
+        return QString();
+
+    qint64 totalSteps = qint64(d->maximum) - d->minimum;
+
+    QString result = d->format;
+    result.replace(QLatin1String("%m"), QString::number(totalSteps));
+    result.replace(QLatin1String("%v"), QString::number(d->value));
+
+    // If max and min are equal and we get this far, it means that the
+    // progress bar has one step and that we are on that step. Return
+    // 100% here in order to avoid division by zero further down.
+    if (totalSteps == 0) {
+        result.replace(QLatin1String("%p"), QString::number(100));
+        return result;
+    }
+
+    int progress = (qreal(d->value) - d->minimum) * 100.0 / totalSteps;
+    result.replace(QLatin1String("%p"), QString::number(progress));
+    return result;
+}
+
+/*!
+    \since 4.1
+    \property QProgressBar::orientation
+    \brief the orientation of the progress bar
+
+    The orientation must be \l Qt::Horizontal (the default) or \l
+    Qt::Vertical.
+
+    \sa invertedAppearance, textDirection
+*/
+
+void QProgressBar::setOrientation(Qt::Orientation orientation)
+{
+    Q_D(QProgressBar);
+    if (d->orientation == orientation)
+        return;
+    d->orientation = orientation;
+    if (!testAttribute(Qt::WA_WState_OwnSizePolicy)) {
+        QSizePolicy sp = sizePolicy();
+        sp.transpose();
+        setSizePolicy(sp);
+        setAttribute(Qt::WA_WState_OwnSizePolicy, false);
+    }
+    d->resetLayoutItemMargins();
+    update();
+    updateGeometry();
+}
+
+Qt::Orientation QProgressBar::orientation() const
+{
+    Q_D(const QProgressBar);
+    return d->orientation;
+}
+
+/*!
+    \since 4.1
+    \property QProgressBar::invertedAppearance
+    \brief whether or not a progress bar shows its progress inverted
+
+    If this property is false, the progress bar grows in the other
+    direction (e.g. from right to left). By default, the progress bar
+    is not inverted.
+
+    \sa orientation, layoutDirection
+*/
+
+void QProgressBar::setInvertedAppearance(bool invert)
+{
+    Q_D(QProgressBar);
+    d->invertedAppearance = invert;
+    update();
+}
+
+bool QProgressBar::invertedAppearance()
+{
+    Q_D(QProgressBar);
+    return d->invertedAppearance;
+}
+
+/*!
+    \since 4.1
+    \property QProgressBar::textDirection
+    \brief the reading direction of the \l text for vertical progress bars
+
+    This property has no impact on horizontal progress bars.
+    By default, the reading direction is QProgressBar::TopToBottom.
+
+    \sa orientation, textVisible
+*/
+void QProgressBar::setTextDirection(QProgressBar::Direction textDirection)
+{
+    Q_D(QProgressBar);
+    d->textDirection = textDirection;
+    update();
+}
+
+QProgressBar::Direction QProgressBar::textDirection()
+{
+    Q_D(QProgressBar);
+    return d->textDirection;
+}
+
+/*! \reimp */
+bool QProgressBar::event(QEvent *e)
+{
+    Q_D(QProgressBar);
+    if (e->type() == QEvent::StyleChange
+#ifdef Q_WS_MAC
+            || e->type() == QEvent::MacSizeChange
+#endif
+            )
+        d->resetLayoutItemMargins();
+    return QWidget::event(e);
+}
+
+/*!
+    \since 4.2
+    \property QProgressBar::format
+    \brief the string used to generate the current text
+
+    %p - is replaced by the percentage completed.
+    %v - is replaced by the current value.
+    %m - is replaced by the total number of steps.
+
+    The default value is "%p%".
+
+    \sa text()
+*/
+void QProgressBar::setFormat(const QString &format)
+{
+    Q_D(QProgressBar);
+    if (d->format == format)
+        return;
+    d->format = format;
+    update();
+}
+
+QString QProgressBar::format() const
+{
+    Q_D(const QProgressBar);
+    return d->format;
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_PROGRESSBAR