source: trunk/src/qt3support/other/q3accel.cpp@ 603

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#include "q3accel.h"

#include "q3signal.h"
#include "qapplication.h"
#include "qwidget.h"
#include "q3ptrlist.h"
#include "qwhatsthis.h"
#include "qpointer.h"
#include "qstatusbar.h"
#include "qdockwidget.h"
#include "qevent.h"
#include "qkeysequence.h"
#include "private/qapplication_p.h"

QT_BEGIN_NAMESPACE

using namespace Qt;

/*!
    \class Q3Accel
    \brief The Q3Accel class handles keyboard accelerator and shortcut keys.

    \compat

    A keyboard accelerator triggers an action when a certain key
    combination is pressed. The accelerator handles all keyboard
    activity for all the children of one top-level widget, so it is
    not affected by the keyboard focus.

    In most cases, you will not need to use this class directly. Use
    the QAction class to create actions with accelerators that can be
    used in both menus and toolbars. If you're only interested in
    menus use Q3MenuData::insertItem() or Q3MenuData::setAccel() to make
    accelerators for operations that are also available on menus. Many
    widgets automatically generate accelerators, such as QAbstractButton,
    QGroupBox, QLabel (with QLabel::setBuddy()), QMenuBar, and QTabBar.
    Example:
    \snippet doc/src/snippets/code/src_qt3support_other_q3accel.cpp 0

    A Q3Accel contains a list of accelerator items that can be
    manipulated using insertItem(), removeItem(), clear(), key() and
    findKey().

    Each accelerator item consists of an identifier and a \l
    QKeySequence. A single key sequence consists of a keyboard code
    combined with modifiers (Qt::SHIFT, Qt::CTRL, Qt::ALT, or
    Qt::UNICODE_ACCEL). For example, Qt::CTRL + Qt::Key_P could be a shortcut
    for printing a document. As an alternative, use Qt::UNICODE_ACCEL with the
    unicode code point of the character. For example, Qt::UNICODE_ACCEL
    + 'A' gives the same accelerator as Qt::Key_A.

    When an accelerator key is pressed, the accelerator sends out the
    signal activated() with a number that identifies this particular
    accelerator item. Accelerator items can also be individually
    connected, so that two different keys will activate two different
    slots (see connectItem() and disconnectItem()).

    The activated() signal is \e not emitted when two or more
    accelerators match the same key.  Instead, the first matching
    accelerator sends out the activatedAmbiguously() signal. By
    pressing the key multiple times, users can navigate between all
    matching accelerators. Some standard controls like QPushButton and
    QCheckBox connect the activatedAmbiguously() signal to the
    harmless setFocus() slot, whereas activated() is connected to a
    slot invoking the button's action. Most controls, like QLabel and
    QTabBar, treat activated() and activatedAmbiguously() as
    equivalent.

    Use setEnabled() to enable or disable all the items in an
    accelerator, or setItemEnabled() to enable or disable individual
    items. An item is active only when both the Q3Accel and the item
    itself are enabled.

    The function setWhatsThis() specifies a help text that appears
    when the user presses an accelerator key in What's This mode.

    The accelerator will be deleted when \e parent is deleted,
    and will consume relevant key events until then.

    Please note that the accelerator
    \snippet doc/src/snippets/code/src_qt3support_other_q3accel.cpp 1
    can be triggered with both the 'M' key, and with Shift+M,
    unless a second accelerator is defined for the Shift+M
    combination.


    Example:
    \snippet doc/src/snippets/code/src_qt3support_other_q3accel.cpp 2

    \sa QKeyEvent QWidget::keyPressEvent()
    QAbstractButton::setAccel() QLabel::setBuddy() QKeySequence
*/


struct Q3AccelItem {                                // internal accelerator item
    Q3AccelItem(const QKeySequence &k, int i)
        { key=k; id=i; enabled=true; signal=0; }
   ~Q3AccelItem()               { delete signal; }
    int id;
    QKeySequence key;
    bool enabled;
    Q3Signal *signal;
    QString whatsthis;
};


typedef Q3PtrList<Q3AccelItem> Q3AccelList; // internal accelerator list

class Q3AccelPrivate {
public:
    Q3AccelPrivate(Q3Accel* p);
    ~Q3AccelPrivate();
    Q3AccelList aitems;
    bool enabled;
    QPointer<QWidget> watch;
    bool ignorewhatsthis;
    Q3Accel* parent;

    void activate(Q3AccelItem* item);
    void activateAmbiguously(Q3AccelItem* item);
};

class Q3AccelManager {
public:
    static Q3AccelManager* self() { return self_ptr ? self_ptr : new Q3AccelManager; }
    void registerAccel(Q3AccelPrivate* a) { accels.append(a); }
    void unregisterAccel(Q3AccelPrivate* a) { accels.removeRef(a); if (accels.isEmpty()) delete this; }
    bool tryAccelEvent(QWidget* w, QKeyEvent* e);
    bool dispatchAccelEvent(QWidget* w, QKeyEvent* e);
    bool tryComposeUnicode(QWidget* w, QKeyEvent* e);

private:
    Q3AccelManager()
        : currentState(QKeySequence::NoMatch), clash(-1), metaComposeUnicode(false),composedUnicode(0)
        { setFuncPtr(); self_ptr = this; }
    ~Q3AccelManager() { self_ptr = 0; }
    void setFuncPtr();

    bool correctSubWindow(QWidget *w, Q3AccelPrivate* d);
    QKeySequence::SequenceMatch match(QKeyEvent* e, Q3AccelItem* item, QKeySequence& temp);
    int translateModifiers(ButtonState state);

    Q3PtrList<Q3AccelPrivate> accels;
    static Q3AccelManager* self_ptr;
    QKeySequence::SequenceMatch currentState;
    QKeySequence intermediate;
    int clash;
    bool metaComposeUnicode;
    int composedUnicode;
};
Q3AccelManager* Q3AccelManager::self_ptr = 0;

bool Q_COMPAT_EXPORT qt_tryAccelEvent(QWidget* w, QKeyEvent*  e){
    return Q3AccelManager::self()->tryAccelEvent(w, e);
}

bool Q_COMPAT_EXPORT qt_dispatchAccelEvent(QWidget* w, QKeyEvent*  e){
    return Q3AccelManager::self()->dispatchAccelEvent(w, e);
}

bool Q_COMPAT_EXPORT qt_tryComposeUnicode(QWidget* w, QKeyEvent*  e){
    return Q3AccelManager::self()->tryComposeUnicode(w, e);
}

void Q3AccelManager::setFuncPtr() {
    if (qApp->d_func()->qt_compat_used)
        return;
    QApplicationPrivate *data = static_cast<QApplicationPrivate*>(qApp->d_ptr.data());
    data->qt_tryAccelEvent = qt_tryAccelEvent;
    data->qt_tryComposeUnicode = qt_tryComposeUnicode;
    data->qt_dispatchAccelEvent = qt_dispatchAccelEvent;
    data->qt_compat_used = true;
}

#ifdef Q_WS_MAC
static bool qt_accel_no_shortcuts = true;
#else
static bool qt_accel_no_shortcuts = false;
#endif
void Q_COMPAT_EXPORT qt_set_accel_auto_shortcuts(bool b) { qt_accel_no_shortcuts = b; }

/*
    \internal
    Returns true if the accel is in the current subwindow, else false.
*/
bool Q3AccelManager::correctSubWindow(QWidget* w, Q3AccelPrivate* d) {
#if !defined (Q_OS_MACX)
     if (!d->watch || !d->watch->isVisible() || !d->watch->isEnabled())
#else
    if (!d->watch || (!d->watch->isVisible() && !d->watch->inherits("QMenuBar")) || !d->watch->isEnabled())
#endif
        return false;
    QWidget* tlw = w->window();
    QWidget* wtlw = d->watch->window();

    /* if we live in a floating dock window, keep our parent's
     * accelerators working */
#ifndef QT_NO_MAINWINDOW
    if ((tlw->windowType() == Qt::Dialog) && tlw->parentWidget() && qobject_cast<QDockWidget*>(tlw))
        return tlw->parentWidget()->window() == wtlw;

    if (wtlw  != tlw)
        return false;
#endif
    /* if we live in a MDI subwindow, ignore the event if we are
       not the active document window */
    QWidget* sw = d->watch;
    while (sw && sw->windowType() != Qt::SubWindow)
        sw = sw->parentWidget(true);
    if (sw)  { // we are in a subwindow indeed
        QWidget* fw = w;
        while (fw && fw != sw)
            fw = fw->parentWidget(true);
        if (fw != sw) // focus widget not in our subwindow
            return false;
    }
    return true;
}

inline int Q3AccelManager::translateModifiers(ButtonState state)
{
    int result = 0;
    if (state & ShiftButton)
        result |= SHIFT;
    if (state & ControlButton)
        result |= CTRL;
    if (state & MetaButton)
        result |= META;
    if (state & AltButton)
        result |= ALT;
    return result;
}

/*
    \internal
    Matches the current intermediate key sequence + the latest
    keyevent, with and AccelItem. Returns Identical,
    PartialMatch or NoMatch, and fills \a temp with the
    resulting key sequence.
*/
QKeySequence::SequenceMatch Q3AccelManager::match(QKeyEvent *e, Q3AccelItem* item, QKeySequence& temp)
{
    QKeySequence::SequenceMatch result = QKeySequence::NoMatch;
    int index = intermediate.count();
    temp = intermediate;

    int modifier = translateModifiers(e->state());

    if (e->key() && e->key() != Key_unknown) {
        int key = e->key()  | modifier;
        if (e->key() == Key_BackTab) {
            /*
            In QApplication, we map shift+tab to shift+backtab.
            This code here reverts the mapping in a way that keeps
            backtab and shift+tab accelerators working, in that
            order, meaning backtab has priority.*/
            key &= ~SHIFT;

            temp.setKey(key, index);
            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))
                return result;
            if (e->state() & ShiftButton)
                key |= SHIFT;
            key = Key_Tab | (key & MODIFIER_MASK);
            temp.setKey(key, index);
            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))
                return result;
        } else {
            temp.setKey(key, index);
            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))
                return result;
        }

        if (key == Key_BackTab) {
            if (e->state() & ShiftButton)
                key |= SHIFT;
            temp.setKey(key, index);
            if (QKeySequence::NoMatch != (result = temp.matches(item->key)))
                return result;
        }
    }
    if (!e->text().isEmpty()) {
        temp.setKey((int)e->text()[0].unicode() | UNICODE_ACCEL | modifier, index);
        result = temp.matches(item->key);
    }
    return result;
}

bool Q3AccelManager::tryAccelEvent(QWidget* w, QKeyEvent* e)
{