//! [0] #ifndef CARD_H #define CARD_H #include #include class CardLayout : public QLayout { public: CardLayout(QWidget *parent, int dist): QLayout(parent, 0, dist) {} CardLayout(QLayout *parent, int dist): QLayout(parent, dist) {} CardLayout(int dist): QLayout(dist) {} ~CardLayout(); void addItem(QLayoutItem *item); QSize sizeHint() const; QSize minimumSize() const; QLayoutItem *count() const; QLayoutItem *itemAt(int) const; QLayoutItem *takeAt(int); void setGeometry(const QRect &rect); private: QList list; }; #endif //! [0] //! [1] //#include "card.h" //! [1] //! [2] QLayoutItem *CardLayout::count() const { // QList::size() returns the number of QLayoutItems in the list return list.size(); } //! [2] //! [3] QLayoutItem *CardLayout::itemAt(int idx) const { // QList::value() performs index checking, and returns 0 if we are // outside the valid range return list.value(idx); } QLayoutItem *CardLayout::takeAt(int idx) { // QList::take does not do index checking return idx >= 0 && idx < list.size() ? list.takeAt(idx) : 0; } //! [3] //! [4] void CardLayout::addItem(QLayoutItem *item) { list.append(item); } //! [4] //! [5] CardLayout::~CardLayout() { QLayoutItem *item; while ((item = takeAt(0))) delete item; } //! [5] //! [6] void CardLayout::setGeometry(const QRect &r) { QLayout::setGeometry(r); if (list.size() == 0) return; int w = r.width() - (list.count() - 1) * spacing(); int h = r.height() - (list.count() - 1) * spacing(); int i = 0; while (i < list.size()) { QLayoutItem *o = list.at(i); QRect geom(r.x() + i * spacing(), r.y() + i * spacing(), w, h); o->setGeometry(geom); ++i; } } //! [6] //! [7] QSize CardLayout::sizeHint() const { QSize s(0,0); int n = list.count(); if (n > 0) s = QSize(100,70); //start with a nice default size int i = 0; while (i < n) { QLayoutItem *o = list.at(i); s = s.expandedTo(o->sizeHint()); ++i; } return s + n*QSize(spacing(), spacing()); } QSize CardLayout::minimumSize() const { QSize s(0,0); int n = list.count(); int i = 0; while (i < n) { QLayoutItem *o = list.at(i); s = s.expandedTo(o->minimumSize()); ++i; } return s + n*QSize(spacing(), spacing()); } //! [7]