qprogressdialog.cpp

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#include "qprogressdialog.h"

#ifndef QT_NO_PROGRESSDIALOG

#include "qshortcut.h"
#include "qpainter.h"
#include "qdrawutil.h"
#include "qlabel.h"
#include "qprogressbar.h"
#include "qapplication.h"
#include "qstyle.h"
#include "qpushbutton.h"
#include "qcursor.h"
#include "qtimer.h"
#include "qelapsedtimer.h"
#include <private/qdialog_p.h>
#include <limits.h>

#if defined(QT_SOFTKEYS_ENABLED)
#include <qaction.h>
#endif
#ifdef Q_WS_S60
#include <QtGui/qdesktopwidget.h>
#endif


QT_BEGIN_NAMESPACE

// If the operation is expected to take this long (as predicted by
// progress time), show the progress dialog.
static const int defaultShowTime = 4000;
// Wait at least this long before attempting to make a prediction.
static const int minWaitTime = 50;

class QProgressDialogPrivate : public QDialogPrivate
{
    Q_DECLARE_PUBLIC(QProgressDialog)

public:
    QProgressDialogPrivate() : label(0), cancel(0), bar(0),
        shown_once(false),
        cancellation_flag(false),
        showTime(defaultShowTime),
#ifndef QT_NO_SHORTCUT
        escapeShortcut(0),
#endif
#ifdef QT_SOFTKEYS_ENABLED
        cancelAction(0),
#endif
        useDefaultCancelText(false)
    {
    }

    void init(const QString &labelText, const QString &cancelText, int min, int max);
    void layout();
    void retranslateStrings();
    void _q_disconnectOnClose();

    QLabel *label;
    QPushButton *cancel;
    QProgressBar *bar;
    QTimer *forceTimer;
    bool shown_once;
    bool cancellation_flag;
    QElapsedTimer starttime;
#ifndef QT_NO_CURSOR
    QCursor parentCursor;
#endif
    int showTime;
    bool autoClose;
    bool autoReset;
    bool forceHide;
#ifndef QT_NO_SHORTCUT
    QShortcut *escapeShortcut;
#endif
#ifdef QT_SOFTKEYS_ENABLED
    QAction *cancelAction;
#endif
    bool useDefaultCancelText;
    QPointer<QObject> receiverToDisconnectOnClose;
    QByteArray memberToDisconnectOnClose;
};

void QProgressDialogPrivate::init(const QString &labelText, const QString &cancelText,
                                  int min, int max)
{
    Q_Q(QProgressDialog);
    label = new QLabel(labelText, q);
    int align = q->style()->styleHint(QStyle::SH_ProgressDialog_TextLabelAlignment, 0, q);
    label->setAlignment(Qt::Alignment(align));
    bar = new QProgressBar(q);
    bar->setRange(min, max);
    autoClose = true;
    autoReset = true;
    forceHide = false;
    QObject::connect(q, SIGNAL(canceled()), q, SLOT(cancel()));
    forceTimer = new QTimer(q);
    QObject::connect(forceTimer, SIGNAL(timeout()), q, SLOT(forceShow()));
    if (useDefaultCancelText) {
        retranslateStrings();
    } else {
        q->setCancelButtonText(cancelText);
    }
}

void QProgressDialogPrivate::layout()
{
    Q_Q(QProgressDialog);
    int sp = q->style()->pixelMetric(QStyle::PM_DefaultLayoutSpacing);
    int mtb = q->style()->pixelMetric(QStyle::PM_DefaultTopLevelMargin);
    int mlr = qMin(q->width() / 10, mtb);
    const bool centered =
        bool(q->style()->styleHint(QStyle::SH_ProgressDialog_CenterCancelButton, 0, q));

    int additionalSpacing = 0;
#ifdef Q_OS_SYMBIAN
    //In Symbian, we need to have wider margins for dialog borders, as the actual border is some pixels
    //inside the dialog area (to enable transparent borders)
    additionalSpacing = mlr;
#endif

    QSize cs = cancel ? cancel->sizeHint() : QSize(0,0);
    QSize bh = bar->sizeHint();
    int cspc;
    int lh = 0;

    // Find spacing and sizes that fit.  It is important that a progress
    // dialog can be made very small if the user demands it so.
    for (int attempt=5; attempt--;) {
        cspc = cancel ? cs.height() + sp : 0;
        lh = qMax(0, q->height() - mtb - bh.height() - sp - cspc);

        if (lh < q->height()/4) {
            // Getting cramped
            sp /= 2;
            mtb /= 2;
            if (cancel) {
                cs.setHeight(qMax(4,cs.height()-sp-2));
            }
            bh.setHeight(qMax(4,bh.height()-sp-1));
        } else {
            break;
        }
    }

    if (cancel) {
        cancel->setGeometry(
            centered ? q->width()/2 - cs.width()/2 : q->width() - mlr - cs.width(),
            q->height() - mtb - cs.height(),
            cs.width(), cs.height());
    }

    if (label)
        label->setGeometry(mlr, additionalSpacing, q->width() - mlr * 2, lh);
    bar->setGeometry(mlr, lh + sp + additionalSpacing, q->width() - mlr * 2, bh.height());
}

void QProgressDialogPrivate::retranslateStrings()
{
    Q_Q(QProgressDialog);
    if (useDefaultCancelText)
        q->setCancelButtonText(QProgressDialog::tr("Cancel"));
}

void QProgressDialogPrivate::_q_disconnectOnClose()
{
    Q_Q(QProgressDialog);
    if (receiverToDisconnectOnClose) {
        QObject::disconnect(q, SIGNAL(canceled()), receiverToDisconnectOnClose,
                            memberToDisconnectOnClose);
        receiverToDisconnectOnClose = 0;
    }
    memberToDisconnectOnClose.clear();
}

QProgressDialog::QProgressDialog(QWidget *parent, Qt::WindowFlags f)
    : QDialog(*(new QProgressDialogPrivate), parent, f)
{
    Q_D(QProgressDialog);
    d->useDefaultCancelText = true;
    d->init(QString::fromLatin1(""), QString(), 0, 100);
}

QProgressDialog::QProgressDialog(const QString &labelText,
                                 const QString &cancelButtonText,
                                 int minimum, int maximum,
                                 QWidget *parent, Qt::WindowFlags f)
    : QDialog(*(new QProgressDialogPrivate), parent, f)
{
    Q_D(QProgressDialog);
    d->init(labelText, cancelButtonText, minimum, maximum);
}


QProgressDialog::~QProgressDialog()
{
}

void QProgressDialog::setLabel(QLabel *label)
{
    Q_D(QProgressDialog);
    delete d->label;
    d->label = label;
    if (label) {
        if (label->parentWidget() == this) {
            label->hide(); // until we resize
        } else {
            label->setParent(this, 0);
        }
    }
    int w = qMax(isVisible() ? width() : 0, sizeHint().width());
    int h = qMax(isVisible() ? height() : 0, sizeHint().height());
    resize(w, h);
    if (label)
        label->show();
}


QString QProgressDialog::labelText() const
{
    Q_D(const QProgressDialog);
    if (d->label)
        return d->label->text();
    return QString();
}

void QProgressDialog::setLabelText(const QString &text)
{
    Q_D(QProgressDialog);
    if (d->label) {
        d->label->setText(text);
        int w = qMax(isVisible() ? width() : 0, sizeHint().width());
        int h = qMax(isVisible() ? height() : 0, sizeHint().height());
        resize(w, h);
    }
}


void QProgressDialog::setCancelButton(QPushButton *cancelButton)
{
    Q_D(QProgressDialog);
    delete d->cancel;
    d->cancel = cancelButton;
    if (cancelButton) {
        if (cancelButton->parentWidget() == this) {
            cancelButton->hide(); // until we resize
        } else {
            cancelButton->setParent(this, 0);
        }
        connect(d->cancel, SIGNAL(clicked()), this, SIGNAL(canceled()));
#ifndef QT_NO_SHORTCUT
        d->escapeShortcut = new QShortcut(Qt::Key_Escape, this, SIGNAL(canceled()));
#endif
    } else {
#ifndef QT_NO_SHORTCUT
        delete d->escapeShortcut;
        d->escapeShortcut = 0;
#endif
    }
    int w = qMax(isVisible() ? width() : 0, sizeHint().width());
    int h = qMax(isVisible() ? height() : 0, sizeHint().height());
    resize(w, h);
    if (cancelButton)
#if !defined(QT_SOFTKEYS_ENABLED)
        cancelButton->show();
#else
    {
        d->cancelAction = new QAction(cancelButton->text(), cancelButton);
        d->cancelAction->setSoftKeyRole(QAction::NegativeSoftKey);
        connect(d->cancelAction, SIGNAL(triggered()), this, SIGNAL(canceled()));
        addAction(d->cancelAction);
    }
#endif
}

void QProgressDialog::setCancelButtonText(const QString &cancelButtonText)
{
    Q_D(QProgressDialog);
    d->useDefaultCancelText = false;

    if (!cancelButtonText.isNull()) {
        if (d->cancel) {
            d->cancel->setText(cancelButtonText);
#ifdef QT_SOFTKEYS_ENABLED
            d->cancelAction->setText(cancelButtonText);
#endif
        } else {
            setCancelButton(new QPushButton(cancelButtonText, this));
        }
    } else {
        setCancelButton(0);
    }
    int w = qMax(isVisible() ? width() : 0, sizeHint().width());
    int h = qMax(isVisible() ? height() : 0, sizeHint().height());
    resize(w, h);
}


void QProgressDialog::setBar(QProgressBar *bar)
{
    Q_D(QProgressDialog);
    if (!bar) {
        qWarning("QProgressDialog::setBar: Cannot set a null progress bar");
        return;
    }
#ifndef QT_NO_DEBUG
    if (value() > 0)
        qWarning("QProgressDialog::setBar: Cannot set a new progress bar "
                  "while the old one is active");
#endif
    delete d->bar;
    d->bar = bar;
    int w = qMax(isVisible() ? width() : 0, sizeHint().width());
    int h = qMax(isVisible() ? height() : 0, sizeHint().height());
    resize(w, h);
}


bool QProgressDialog::wasCanceled() const
{
    Q_D(const QProgressDialog);
    return d->cancellation_flag;
}


int QProgressDialog::maximum() const
{
    Q_D(const QProgressDialog);
    return d->bar->maximum();
}

void QProgressDialog::setMaximum(int maximum)
{
    Q_D(QProgressDialog);
    d->bar->setMaximum(maximum);
}

int QProgressDialog::minimum() const
{
    Q_D(const QProgressDialog);
    return d->bar->minimum();
}

void QProgressDialog::setMinimum(int minimum)
{
    Q_D(QProgressDialog);
    d->bar->setMinimum(minimum);
}

void QProgressDialog::setRange(int minimum, int maximum)
{
    Q_D(QProgressDialog);
    d->bar->setRange(minimum, maximum);
}


void QProgressDialog::reset()
{
    Q_D(QProgressDialog);
#ifndef QT_NO_CURSOR
    if (value() >= 0) {
        if (parentWidget())
            parentWidget()->setCursor(d->parentCursor);
    }
#endif
    if (d->autoClose || d->forceHide)
        hide();
    d->bar->reset();
    d->cancellation_flag = false;
    d->shown_once = false;
    d->forceTimer->stop();

    /*
        I wish we could disconnect the user slot provided to open() here but
        unfortunately reset() is usually called before the slot has been invoked.
        (reset() is itself invoked when canceled() is emitted.)
    */
    if (d->receiverToDisconnectOnClose)
        QMetaObject::invokeMethod(this, "_q_disconnectOnClose", Qt::QueuedConnection);
}

void QProgressDialog::cancel()
{
    Q_D(QProgressDialog);
    d->forceHide = true;
    reset();
    d->forceHide = false;
    d->cancellation_flag = true;
}


int QProgressDialog::value() const
{
    Q_D(const QProgressDialog);
    return d->bar->value();
}

void QProgressDialog::setValue(int progress)
{
    Q_D(QProgressDialog);
    if (progress == d->bar->value()
        || (d->bar->value() == -1 && progress == d->bar->maximum()))
        return;

    d->bar->setValue(progress);

    if (d->shown_once) {
        if (isModal())
            QApplication::processEvents();
    } else {
        if (progress == 0) {
            d->starttime.start();
            d->forceTimer->start(d->showTime);
            return;
        } else {
            bool need_show;
            int elapsed = d->starttime.elapsed();
            if (elapsed >= d->showTime) {
                need_show = true;
            } else {
                if (elapsed > minWaitTime) {
                    int estimate;
                    int totalSteps = maximum() - minimum();
                    int myprogress = progress - minimum();
                    if (myprogress == 0) myprogress = 1;
                    if ((totalSteps - myprogress) >= INT_MAX / elapsed)
                        estimate = (totalSteps - myprogress) / myprogress * elapsed;
                    else
                        estimate = elapsed * (totalSteps - myprogress) / myprogress;
                    need_show = estimate >= d->showTime;
                } else {
                    need_show = false;
                }
            }
            if (need_show) {
                int w = qMax(isVisible() ? width() : 0, sizeHint().width());
                int h = qMax(isVisible() ? height() : 0, sizeHint().height());
                resize(w, h);
                show();
                d->shown_once = true;
            }
        }
#ifdef Q_WS_MAC
        QApplication::flush();
#endif
    }

    if (progress == d->bar->maximum() && d->autoReset)
        reset();
}

QSize QProgressDialog::sizeHint() const
{
    Q_D(const QProgressDialog);
    QSize sh = d->label ? d->label->sizeHint() : QSize(0, 0);
    QSize bh = d->bar->sizeHint();
    int margin = style()->pixelMetric(QStyle::PM_DefaultTopLevelMargin);
    int spacing = style()->pixelMetric(QStyle::PM_DefaultLayoutSpacing);
    int h = margin * 2 + bh.height() + sh.height() + spacing;
    if (d->cancel)
        h += d->cancel->sizeHint().height() + spacing;
#ifdef Q_WS_S60
    if (QApplication::desktop()->size().height() > QApplication::desktop()->size().width())
        return QSize(qMax(QApplication::desktop()->size().width(), sh.width() + 2 * margin), h);
    else
        return QSize(qMax(QApplication::desktop()->size().height(), sh.width() + 2 * margin), h);
#else
    return QSize(qMax(200, sh.width() + 2 * margin), h);
#endif
}

void QProgressDialog::resizeEvent(QResizeEvent *)
{
    Q_D(QProgressDialog);
    d->layout();
}

void QProgressDialog::changeEvent(QEvent *ev)
{
    Q_D(QProgressDialog);
    if (ev->type() == QEvent::StyleChange) {
        d->layout();
    } else if (ev->type() == QEvent::LanguageChange) {
        d->retranslateStrings();
    }
    QDialog::changeEvent(ev);
}

void QProgressDialog::setMinimumDuration(int ms)
{
    Q_D(QProgressDialog);
    d->showTime = ms;
    if (d->bar->value() == 0) {
        d->forceTimer->stop();
        d->forceTimer->start(ms);
    }
}

int QProgressDialog::minimumDuration() const
{
    Q_D(const QProgressDialog);
    return d->showTime;
}


void QProgressDialog::closeEvent(QCloseEvent *e)
{
    emit canceled();
    QDialog::closeEvent(e);
}

void QProgressDialog::setAutoReset(bool b)
{
    Q_D(QProgressDialog);
    d->autoReset = b;
}

bool QProgressDialog::autoReset() const
{
    Q_D(const QProgressDialog);
    return d->autoReset;
}

void QProgressDialog::setAutoClose(bool close)
{
    Q_D(QProgressDialog);
    d->autoClose = close;
}

bool QProgressDialog::autoClose() const
{
    Q_D(const QProgressDialog);
    return d->autoClose;
}

void QProgressDialog::showEvent(QShowEvent *e)
{
    Q_D(QProgressDialog);
    QDialog::showEvent(e);
    int w = qMax(isVisible() ? width() : 0, sizeHint().width());
    int h = qMax(isVisible() ? height() : 0, sizeHint().height());
    resize(w, h);
    d->forceTimer->stop();
}

void QProgressDialog::forceShow()
{
    Q_D(QProgressDialog);
    d->forceTimer->stop();
    if (d->shown_once || d->cancellation_flag)
        return;

    show();
    d->shown_once = true;
}

void QProgressDialog::open(QObject *receiver, const char *member)
{
    Q_D(QProgressDialog);
    connect(this, SIGNAL(canceled()), receiver, member);
    d->receiverToDisconnectOnClose = receiver;
    d->memberToDisconnectOnClose = member;
    QDialog::open();
}

QT_END_NAMESPACE

#include "moc_qprogressdialog.cpp"

#endif // QT_NO_PROGRESSDIALOG