qtabbar.cpp

qtopia-phone-2.2.0下公共的控件实现源代码。

/*!
  Repaints the tab row.  All the painting is done by paint();
  paintEvent() only decides which tabs need painting and in what
  order.

  \sa paint()
*/

void QTabBar::paintEvent( QPaintEvent * e )
{
    QPainter p( this );

    if ( backgroundMode() == X11ParentRelative ) {
	erase();
    } else {
	if ( !testWState(WState_GlobalBrushOrigin) ) 
	    p.setBrushOrigin( rect().bottomLeft() );
	p.fillRect( 0, 0, width(), height(),
		    QBrush( colorGroup().brush( QColorGroup::Background ) ));
    }

    QTab * t;
    t = l->first();
    do {
	QTab * n = l->next();
	if ( t && t->r.intersects( e->rect() ) )
	    paint( &p, t, n == 0 );
	t = n;
    } while ( t != 0 );

    if ( d->scrolls && lstatic->first()->r.left() < 0 ) {
	QPointArray a;
	int h = height();
	if ( d->s == RoundedAbove ) {
	    p.fillRect( 0, 3, 4, h-5,
			QBrush( colorGroup().brush( QColorGroup::Background ) ));
	    a.setPoints( 5,  0,2,  3,h/4, 0,h/2, 3,3*h/4, 0,h );
	} else if ( d->s == RoundedBelow ) {
	    p.fillRect( 0, 2, 4, h-5,
			QBrush( colorGroup().brush( QColorGroup::Background ) ));
	    a.setPoints( 5,  0,0,  3,h/4, 0,h/2, 3,3*h/4, 0,h-3 );
	}

	if ( !a.isEmpty() ) {
	    p.setPen( colorGroup().light() );
	    p.drawPolyline( a );
	    a.translate( 1, 0 );
	    p.setPen( colorGroup().midlight() );
	    p.drawPolyline( a );
	}
    }
}


/*!
  This virtual functions is called by the mouse event handlers to
  determine which tab is pressed.  The default implementation returns
  a pointer to the tab whose bounding rectangle contains \a p, if
  exactly one tab's bounding rectangle contains \a p.  It returns 0
  else.

  \sa mousePressEvent() mouseReleaseEvent()
*/

QTab * QTabBar::selectTab( const QPoint & p ) const
{
    QTab * selected = 0;
    bool moreThanOne = FALSE;

    QListIterator<QTab> i( *l );
    while( i.current() ) {
	QTab * t = i.current();
	++i;

	if ( t && t->r.contains( p ) ) {
	    if ( selected )
		moreThanOne = TRUE;
	    else
		selected = t;
	}
    }

    return moreThanOne ? 0 : selected;
}


/*!\reimp
*/
void QTabBar::mousePressEvent( QMouseEvent * e )
{
    if ( e->button() != LeftButton )
	return;
    QTab * t = selectTab( e->pos() );
    if ( t != 0 && t == selectTab( e->pos() ) && t->enabled ) {
	setCurrentTab( t );
    }
}


/*!\reimp
*/

void QTabBar::mouseReleaseEvent( QMouseEvent * )
{
}


/*!  \reimp
*/
void QTabBar::show()
{
    //  ensures that one tab is selected.
    QTab * t = l->last();
    QWidget::show();
#ifdef QT_KEYPAD_MODE
    // grab focus to make tab navigation easier
    if( qt_modalEditingEnabled ) {
	setFocus();
    }
#endif

    if ( t )
	emit selected( t->id );
}

/*!  If a page is currently visible, returns its ID.  If no page is
  currently visible, returns either -1 or the ID of one of the pages.

  Even if the return value is not -1, you cannot assume either that
  the user can see the relevant page, or that the tab \link
  isTabEnabled() is enabled.\endlink

  When you need to display something, the return value from this
  function represents the best page to display.  That's all.

  \sa selected()
*/

int QTabBar::currentTab() const
{
    const QTab * t = l->getLast();

    return t ? t->id : -1;
}


/*! Raises the tab with ID \a id and emits the selected() signal.

  \sa currentTab() selected() tab()
*/

void QTabBar::setCurrentTab( int id )
{
    setCurrentTab( tab( id ) );
}


/*! Raises \a tab and emits the selected() signal unless the tab was
  already current.

  \sa currentTab() selected()
*/

void QTabBar::setCurrentTab( QTab * tab )
{
    if ( tab && l ) {
	if ( l->last() == tab )
	    return;

	QRect r = l->last()->r;
	if ( l->findRef( tab ) >= 0 )
	    l->append( l->take() );

	d->focus = tab->id;
	updateMask();
	if ( tab->r.intersects( r ) ) {
	    repaint( r.unite( tab->r ) );
	} else {
	    repaint( r );
	    repaint( tab->r );
	}
	makeVisible( tab );
	emit selected( tab->id );
    }
}

/*!  If this tab control has keyboard focus, returns the ID of the
  tab Space will select.  Otherwise, returns -1.
*/

int QTabBar::keyboardFocusTab() const
{
    return hasFocus() ? d->focus : -1;
}


/*!\reimp
*/
void QTabBar::keyPressEvent( QKeyEvent * e )
{
    //   The right and left arrow keys move a selector, the spacebar
    //   makes the tab with the selector active.  All other keys are
    //   ignored.

    int old = d->focus;

    if ( e->key() == Key_Left ) {
	// left - skip past any disabled ones
	QTab *t = 0;
	if ( d->focus > 0 ) {
	    t = lstatic->last();
	    while ( t && t->id != d->focus )
		t = lstatic->prev();
	    do {
		t = lstatic->prev();
	    } while ( t && !t->enabled);
	    if (t)
		d->focus = t->id;
	}
#ifdef QT_KEYPAD_MODE
	if( qt_modalEditingEnabled ) {
	    if (!t) {
		t = lstatic->last();
		while ( t && !t->enabled)
		    t = lstatic->prev();
		if (t)
		    d->focus = t->id;
	    }
	}
#endif
	if ( d->focus < 0 )
	    d->focus = old;
    } else if ( e->key() == Key_Right 
#ifdef QT_KEYPAD_MODE
		|| (qt_modalEditingEnabled && e->key() == Key_Select)
#endif
	      ) {
	QTab * t = lstatic->first();
	while ( t && t->id != d->focus )
	    t = lstatic->next();
	do {
	    t = lstatic->next();
	} while ( t && !t->enabled);
	if (t)
	    d->focus = t->id;
#ifdef QT_KEYPAD_MODE
	else if( qt_modalEditingEnabled ) {
	    t = lstatic->first();
	    while ( t && !t->enabled)
		t = lstatic->next();
	    if (t)
		d->focus = t->id;
	}
#endif
	if ( d->focus >= d->id )
	    d->focus = old;
    } else {
	// other keys - ignore
	e->ignore();
	return;
    }

    // if the focus moved, repaint and signal
    if ( old != d->focus ) {
	setCurrentTab( d->focus );
    }
}


/*!  Returns a pointer to the tab with ID \a id, or 0 if there is no
  such tab.

  \sa count()
*/

QTab * QTabBar::tab( int id )
{
    QTab * t;
    for( t = l->first(); t; t = l->next() )
	if ( t && t->id == id )
	    return t;
    return 0;
}


/*! Returns the number of tabs in the tab bar.

  \sa tab()
*/
int QTabBar::count() const
{
    return l->count();
}


/*!
  The list of QTab objects added.
*/
QList<QTab> * QTabBar::tabList()
{
    return l;
}


/*!  Returns the shape of this tab bar. \sa setShape() */

QTabBar::Shape QTabBar::shape() const
{
    return d ? d->s : RoundedAbove;
}


/*!  Sets the shape of this tab bar to \a s and refreshes the bar.
*/

void QTabBar::setShape( Shape s )
{
    if ( !d || d->s == s )
	return;
    //######### must recalculate heights
    d->s = s;
    updateMask();
    update();
}



/*!
  Layout all existing tabs (i.e. setting their \c r attribute) according
  to their label and their iconset.
 */
void QTabBar::layoutTabs()
{
    if ( lstatic->isEmpty() )
	return;

    int hframe, vframe, overlap;
    style().tabbarMetrics( this, hframe, vframe, overlap );
    QFontMetrics fm = fontMetrics();
    int x = 0;
    QRect r;
    QTab *t;
    for ( t = lstatic->first(); t; t = lstatic->next() ) {
	int lw = fm.width( t->label );
	int iw = 0;
	int ih = 0;
	if ( t->iconset != 0 ) {
	    iw = t->iconset->pixmap( QIconSet::Small, QIconSet::Normal ).width();
	    ih = t->iconset->pixmap( QIconSet::Small, QIconSet::Normal ).height();
	    if (!t->label.isNull())
		iw +=2;
	}
	int h = QMAX( fm.height(), ih );
	h = QMAX( h, QApplication::globalStrut().height() );

	h += vframe;
	t->r.setRect( x, 0, QMAX( lw + hframe + iw,
		    QApplication::globalStrut().width() ), h );
	x += t->r.width() - overlap;
	r = r.unite( t->r );
    }
    for ( t = lstatic->first(); t; t = lstatic->next() )
	t->r.setHeight( r.height() );
}

/*!
  \reimp
*/

void QTabBar::styleChange( QStyle& old )
{
	layoutTabs();
	QWidget::styleChange( old );
}

/*!
  \reimp
*/
void QTabBar::focusInEvent( QFocusEvent * )
{
    QTab *t = l->first();
    for ( ; t; t = l->next() ) {
	if ( t->id == d->focus ) {
	    QPainter p;
	    p.begin( this );
	    QRect r = t->r;
	    p.setFont( font() );

	    int iw = 0;
	    int ih = 0;
	    if ( t->iconset != 0 ) {
		iw = t->iconset->pixmap( QIconSet::Small, QIconSet::Normal ).width();
		ih = t->iconset->pixmap( QIconSet::Small, QIconSet::Normal ).height();
		if (!t->label.isEmpty())
		    iw +=2; 
	    }
	    int w = iw + p.fontMetrics().width( t->label ) + 4 + style().pixelMetric(QStyle::TabHMargin);
	    int h = QMAX(p.fontMetrics().height() + 4, ih );
	    paintLabel( &p, QRect( r.left() + ( r.width() -w ) /2,
				   r.top() + ( r.height()-h ) / 2,
				   w, h ), t, TRUE );
	    p.end();
	}
    }
}

/*!
  \reimp
*/
void QTabBar::focusOutEvent( QFocusEvent * )
{
    QTab *t = l->first();
    for ( ; t; t = l->next() ) {
	if ( t->id == d->focus ) {
	    QPainter p;
	    p.begin( this );
	    if ( !testWState(WState_GlobalBrushOrigin) ) 
		p.setBrushOrigin( rect().bottomLeft() );
	    QRect r = t->r;
	    p.setFont( font() );

	    int iw = 0;
	    int ih = 0;
	    if ( t->iconset != 0 ) {
		iw = t->iconset->pixmap( QIconSet::Small, QIconSet::Normal ).width();
		ih = t->iconset->pixmap( QIconSet::Small, QIconSet::Normal ).height();
		if (!t->label.isEmpty())
		    iw +=2; 
	    }
	    int w = iw + p.fontMetrics().width( t->label ) + 4 + style().pixelMetric(QStyle::TabHMargin);
	    int h = QMAX(p.fontMetrics().height() + 4, ih );
	    p.fillRect( QRect( r.left() + ( r.width() -w ) / 2 - 1,
				   r.top() + ( r.height()-h ) / 2 - 1,
			       w + 2, h + 2 ), colorGroup().brush(QColorGroup::Background ) );
	    style().drawTab( &p, this, t, TRUE );
	    paintLabel( &p, QRect( r.left() + ( r.width() -w ) /2,
				   r.top() + ( r.height()-h ) / 2,
				   w, h ), t, FALSE );
	    p.end();
	}
    }
}

/*!
  \reimp
*/
void QTabBar::resizeEvent( QResizeEvent * )
{
#ifndef QT_NO_TOOLBUTTON
    const int arrowWidth = 16;
    d->rightB->setGeometry( width() - arrowWidth, 0, arrowWidth, height() );
    d->leftB->setGeometry( width() - 2*arrowWidth, 0, arrowWidth, height() );
#endif
    layoutTabs();
    updateArrowButtons();
    makeVisible( tab( currentTab() ));
}

void QTabBar::scrollTabs()
{
#ifndef QT_NO_TOOLBUTTON
    QTab* left = 0;
    QTab* right = 0;
    for ( QTab* t = lstatic->first(); t; t = lstatic->next() ) {
	if ( t->r.left() < 0 && t->r.right() > 0 )
	    left = t;
	if ( t->r.left() < d->leftB->x()+2 )
	    right = t;
    }

    if ( sender() == d->leftB )
	makeVisible( left );
    else  if ( sender() == d->rightB )
	makeVisible( right );
#endif
}

void QTabBar::makeVisible( QTab* tab  )
{
#ifndef QT_NO_TOOLBUTTON
    bool tooFarLeft = ( tab && tab->r.left() < 0 );
    bool tooFarRight = ( tab && tab->r.right() >= d->leftB->x() );

    if ( !d->scrolls || ( !tooFarLeft && ! tooFarRight ) )
	return;

    layoutTabs();

    int offset = 0;

    if ( tooFarLeft )
	offset = tab == lstatic->first() ? 0 : tab->r.left() - 8;
    else if ( tooFarRight ) {
	offset = tab->r.right() - d->leftB->x() + 1;
    }

    for ( QTab* t = lstatic->first(); t; t = lstatic->next() )
	t->r.moveBy( -offset, 0 );

    d->leftB->setEnabled( offset != 0 );
    d->rightB->setEnabled( lstatic->last()->r.right() >= d->leftB->x() );


    update();
#endif
}

void QTabBar::updateArrowButtons()
{
#ifndef QT_NO_TOOLBUTTON
    bool b = lstatic->last() &&	( lstatic->last()->r.right() > width() );
    d->scrolls = b;
    if ( d->scrolls ) {
	d->leftB->setEnabled( FALSE );
	d->rightB->setEnabled( TRUE );
	d->leftB->show();
	d->rightB->show();
    } else {
	d->leftB->hide();
	d->rightB->hide();
    }
#endif
}
#endif