PuzzleWidget Class Reference

#include <puzzlewidget.h>

Inheritance diagram for PuzzleWidget:

[legend]Collaboration diagram for PuzzleWidget:

[legend]List of all members.

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Detailed Description

Definition at line 36 of file puzzlewidget.h.

Signals
void	puzzleCompleted ()
void	puzzleCompleted ()
Public Member Functions
	PuzzleWidget (QWidget *parent=0)
void	clear ()
	PuzzleWidget (QWidget *parent=0)
void	clear ()
Protected Member Functions
void	dragEnterEvent (QDragEnterEvent *event)
void	dragLeaveEvent (QDragLeaveEvent *event)
void	dragMoveEvent (QDragMoveEvent *event)
void	dropEvent (QDropEvent *event)
void	mousePressEvent (QMouseEvent *event)
void	paintEvent (QPaintEvent *event)
void	dragEnterEvent (QDragEnterEvent *event)
void	dragLeaveEvent (QDragLeaveEvent *event)
void	dragMoveEvent (QDragMoveEvent *event)
void	dropEvent (QDropEvent *event)
void	mousePressEvent (QMouseEvent *event)
void	paintEvent (QPaintEvent *event)
Private Member Functions
int	findPiece (const QRect &pieceRect) const
const QRect	targetSquare (const QPoint &position) const
int	findPiece (const QRect &pieceRect) const
const QRect	targetSquare (const QPoint &position) const
Private Attributes
QList< QPixmap >	piecePixmaps
QList< QRect >	pieceRects
QList< QPoint >	pieceLocations
QRect	highlightedRect
int	inPlace
QList< QPixmap >	piecePixmaps
QList< QRect >	pieceRects
QList< QPoint >	pieceLocations

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Constructor & Destructor Documentation

PuzzleWidget::PuzzleWidget

(

QWidget *

parent = 0

)

Definition at line 28 of file puzzlewidget.cpp.

References QWidget::setAcceptDrops(), QWidget::setMaximumSize(), and QWidget::setMinimumSize().

    : QWidget(parent)
{
    setAcceptDrops(true);
    setMinimumSize(400, 400);
    setMaximumSize(400, 400);
}

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PuzzleWidget::PuzzleWidget

(

QWidget *

parent = 0

)

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Member Function Documentation

void PuzzleWidget::clear

(

)

Definition at line 36 of file puzzlewidget.cpp.

References QList< T >::clear(), highlightedRect, inPlace, pieceLocations, piecePixmaps, pieceRects, and QWidget::update().

Referenced by MainWindow::setupPuzzle().

{
    pieceLocations.clear();
    piecePixmaps.clear();
    pieceRects.clear();
    highlightedRect = QRect();
    inPlace = 0;
    update();
}

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void PuzzleWidget::puzzleCompleted

(

)

[signal]

Referenced by dropEvent().

void PuzzleWidget::dragEnterEvent

(

QDragEnterEvent *

event

)

[protected, virtual]

This event handler is called when a drag is in progress and the mouse enters this widget. The event is passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDragEnterEvent

Reimplemented from QWidget.

Definition at line 46 of file puzzlewidget.cpp.

References QWidget::event().

{
    if (event->mimeData()->hasFormat("image/x-puzzle-piece"))
        event->accept();
    else
        event->ignore();
}

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void PuzzleWidget::dragLeaveEvent

(

QDragLeaveEvent *

event

)

[protected, virtual]

This event handler is called when a drag is in progress and the mouse leaves this widget. The event is passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDragLeaveEvent

Reimplemented from QWidget.

Definition at line 54 of file puzzlewidget.cpp.

References QWidget::event(), highlightedRect, and QWidget::update().

{
    QRect updateRect = highlightedRect;
    highlightedRect = QRect();
    update(updateRect);
    event->accept();
}

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void PuzzleWidget::dragMoveEvent

(

QDragMoveEvent *

event

)

[protected, virtual]

This event handler is called if a drag is in progress, and when any of the following conditions occurs: the cursor enters this widget, the cursor moves within this widget, or a modifier key is pressed on the keyboard while this widget has the focus. The event is passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDragMoveEvent

Reimplemented from QWidget.

Definition at line 62 of file puzzlewidget.cpp.

References QWidget::event(), findPiece(), highlightedRect, Qt::MoveAction, targetSquare(), QRect::unite(), and QWidget::update().

{
    QRect updateRect = highlightedRect.unite(targetSquare(event->pos()));

    if (event->mimeData()->hasFormat("image/x-puzzle-piece")
        && findPiece(targetSquare(event->pos())) == -1) {

        highlightedRect = targetSquare(event->pos());
        event->setDropAction(Qt::MoveAction);
        event->accept();
    } else {
        highlightedRect = QRect();
        event->ignore();
    }

    update(updateRect);
}

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void PuzzleWidget::dropEvent

(

QDropEvent *

event

)

[protected, virtual]

This event handler is called when the drag is dropped on this widget which are passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDropEvent

Reimplemented from QWidget.

Definition at line 80 of file puzzlewidget.cpp.

References QList< T >::append(), emit, QWidget::event(), findPiece(), highlightedRect, inPlace, location, Qt::MoveAction, pieceLocations, piecePixmaps, pieceRects, puzzleCompleted(), QIODevice::ReadOnly, targetSquare(), QWidget::update(), QRect::x(), and QRect::y().

{
    if (event->mimeData()->hasFormat("image/x-puzzle-piece")
        && findPiece(targetSquare(event->pos())) == -1) {

        QByteArray pieceData = event->mimeData()->data("image/x-puzzle-piece");
        QDataStream dataStream(&pieceData, QIODevice::ReadOnly);
        QRect square = targetSquare(event->pos());
        QPixmap pixmap;
        QPoint location;
        dataStream >> pixmap >> location;

        pieceLocations.append(location);
        piecePixmaps.append(pixmap);
        pieceRects.append(square);

        highlightedRect = QRect();
        update(square);

        event->setDropAction(Qt::MoveAction);
        event->accept();

        if (location == QPoint(square.x()/80, square.y()/80)) {
            inPlace++;
            if (inPlace == 25)
                emit puzzleCompleted();
        }
    } else {
        highlightedRect = QRect();
        event->ignore();
    }
}

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void PuzzleWidget::mousePressEvent

(

QMouseEvent *

event

)

[protected, virtual]

This event handler, for event event, can be reimplemented in a subclass to receive mouse press events for the widget.

If you create new widgets in the mousePressEvent() the mouseReleaseEvent() may not end up where you expect, depending on the underlying window system (or X11 window manager), the widgets' location and maybe more.

The default implementation implements the closing of popup widgets when you click outside the window. For other widget types it does nothing.

See also:

mouseReleaseEvent(), mouseDoubleClickEvent(), mouseMoveEvent(), event(), QMouseEvent, {Scribble Example}

Reimplemented from QWidget.

Definition at line 123 of file puzzlewidget.cpp.

References QWidget::event(), findPiece(), inPlace, QList< T >::insert(), location, Qt::MoveAction, pieceLocations, piecePixmaps, pieceRects, QList< T >::removeAt(), QMimeData::setData(), QDrag::setHotSpot(), QDrag::setMimeData(), QDrag::setPixmap(), QDrag::start(), targetSquare(), QRect::topLeft(), QWidget::update(), QIODevice::WriteOnly, QRect::x(), and QRect::y().

{
    QRect square = targetSquare(event->pos());
    int found = findPiece(square);

    if (found == -1)
        return;

    QPoint location = pieceLocations[found];
    QPixmap pixmap = piecePixmaps[found];
    pieceLocations.removeAt(found);
    piecePixmaps.removeAt(found);
    pieceRects.removeAt(found);

    if (location == QPoint(square.x()/80, square.y()/80))
        inPlace--;

    update(square);

    QByteArray itemData;
    QDataStream dataStream(&itemData, QIODevice::WriteOnly);

    dataStream << pixmap << location;

    QMimeData *mimeData = new QMimeData;
    mimeData->setData("image/x-puzzle-piece", itemData);

    QDrag *drag = new QDrag(this);
    drag->setMimeData(mimeData);
    drag->setHotSpot(event->pos() - square.topLeft());
    drag->setPixmap(pixmap);

    if (!(drag->start(Qt::MoveAction) == Qt::MoveAction)) {
        pieceLocations.insert(found, location);
        piecePixmaps.insert(found, pixmap);
        pieceRects.insert(found, square);
        update(targetSquare(event->pos()));

        if (location == QPoint(square.x()/80, square.y()/80))
            inPlace++;
    }
}

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void PuzzleWidget::paintEvent

(

QPaintEvent *

event

)

[protected, virtual]

This event handler can be reimplemented in a subclass to receive paint events which are passed in the event parameter.

A paint event is a request to repaint all or part of the widget. It can happen as a result of repaint() or update(), or because the widget was obscured and has now been uncovered, or for many other reasons.

Many widgets can simply repaint their entire surface when asked to, but some slow widgets need to optimize by painting only the requested region: QPaintEvent::region(). This speed optimization does not change the result, as painting is clipped to that region during event processing. QListView and QTableView do this, for example.

Qt also tries to speed up painting by merging multiple paint events into one. When update() is called several times or the window system sends several paint events, Qt merges these events into one event with a larger region (see QRegion::united()). repaint() does not permit this optimization, so we suggest using update() whenever possible.

When the paint event occurs, the update region has normally been erased, so that you're painting on the widget's background.

The background can be set using setBackgroundRole() and setPalette().

From Qt 4.0, QWidget automatically double-buffers its painting, so there's no need to write double-buffering code in paintEvent() to avoid flicker.

Note: Under X11 it is possible to toggle the global double buffering by calling qt_x11_set_global_double_buffer(). Example usage:

    ...
    extern void qt_x11_set_global_double_buffer(bool);
    qt_x11_set_global_double_buffer(false);
    ...

See also:

event(), repaint(), update(), QPainter, QPixmap, QPaintEvent, {Analog Clock Example}

Reimplemented from QWidget.

Definition at line 166 of file puzzlewidget.cpp.

References QRect::adjusted(), QPainter::begin(), QPainter::drawPixmap(), QPainter::drawRect(), QPainter::end(), QWidget::event(), QPainter::fillRect(), highlightedRect, i, QRect::isValid(), Qt::NoPen, piecePixmaps, pieceRects, QPainter::setBrush(), QPainter::setPen(), QList< T >::size(), and Qt::white.

{
    QPainter painter;
    painter.begin(this);
    painter.fillRect(event->rect(), Qt::white);

    if (highlightedRect.isValid()) {
        painter.setBrush(QColor("#ffcccc"));
        painter.setPen(Qt::NoPen);
        painter.drawRect(highlightedRect.adjusted(0, 0, -1, -1));
    }

    for (int i = 0; i < pieceRects.size(); ++i) {
        painter.drawPixmap(pieceRects[i], piecePixmaps[i]);
    }
    painter.end();
}

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int PuzzleWidget::findPiece

(

const QRect &

pieceRect

)

const [private]

Definition at line 113 of file puzzlewidget.cpp.

References i, pieceRects, and QList< T >::size().

Referenced by dragMoveEvent(), dropEvent(), and mousePressEvent().

{
    for (int i = 0; i < pieceRects.size(); ++i) {
        if (pieceRect == pieceRects[i]) {
            return i;
        }
    }
    return -1;
}

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const QRect PuzzleWidget::targetSquare

(

const QPoint &

position

)

const [private]

Definition at line 184 of file puzzlewidget.cpp.

References QPoint::x(), and QPoint::y().

Referenced by dragMoveEvent(), dropEvent(), and mousePressEvent().

{
    return QRect(position.x()/80 * 80, position.y()/80 * 80, 80, 80);
}

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void PuzzleWidget::clear

(

)

void PuzzleWidget::puzzleCompleted

(

)

[signal]

void PuzzleWidget::dragEnterEvent

(

QDragEnterEvent *

event

)

[protected, virtual]

This event handler is called when a drag is in progress and the mouse enters this widget. The event is passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDragEnterEvent

Reimplemented from QWidget.

void PuzzleWidget::dragLeaveEvent

(

QDragLeaveEvent *

event

)

[protected, virtual]

This event handler is called when a drag is in progress and the mouse leaves this widget. The event is passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDragLeaveEvent

Reimplemented from QWidget.

void PuzzleWidget::dragMoveEvent

(

QDragMoveEvent *

event

)

[protected, virtual]

This event handler is called if a drag is in progress, and when any of the following conditions occurs: the cursor enters this widget, the cursor moves within this widget, or a modifier key is pressed on the keyboard while this widget has the focus. The event is passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDragMoveEvent

Reimplemented from QWidget.

void PuzzleWidget::dropEvent

(

QDropEvent *

event

)

[protected, virtual]

This event handler is called when the drag is dropped on this widget which are passed in the event parameter.

See the Drag-and-drop documentation for an overview of how to provide drag-and-drop in your application.

See also:

QTextDrag, QImageDrag, QDropEvent

Reimplemented from QWidget.

void PuzzleWidget::mousePressEvent

(

QMouseEvent *

event

)

[protected, virtual]

This event handler, for event event, can be reimplemented in a subclass to receive mouse press events for the widget.

If you create new widgets in the mousePressEvent() the mouseReleaseEvent() may not end up where you expect, depending on the underlying window system (or X11 window manager), the widgets' location and maybe more.

The default implementation implements the closing of popup widgets when you click outside the window. For other widget types it does nothing.

See also:

mouseReleaseEvent(), mouseDoubleClickEvent(), mouseMoveEvent(), event(), QMouseEvent, {Scribble Example}

Reimplemented from QWidget.

void PuzzleWidget::paintEvent

(

QPaintEvent *

event

)

[protected, virtual]

This event handler can be reimplemented in a subclass to receive paint events which are passed in the event parameter.

A paint event is a request to repaint all or part of the widget. It can happen as a result of repaint() or update(), or because the widget was obscured and has now been uncovered, or for many other reasons.

Many widgets can simply repaint their entire surface when asked to, but some slow widgets need to optimize by painting only the requested region: QPaintEvent::region(). This speed optimization does not change the result, as painting is clipped to that region during event processing. QListView and QTableView do this, for example.

Qt also tries to speed up painting by merging multiple paint events into one. When update() is called several times or the window system sends several paint events, Qt merges these events into one event with a larger region (see QRegion::united()). repaint() does not permit this optimization, so we suggest using update() whenever possible.

When the paint event occurs, the update region has normally been erased, so that you're painting on the widget's background.

The background can be set using setBackgroundRole() and setPalette().

From Qt 4.0, QWidget automatically double-buffers its painting, so there's no need to write double-buffering code in paintEvent() to avoid flicker.

Note: Under X11 it is possible to toggle the global double buffering by calling qt_x11_set_global_double_buffer(). Example usage:

    ...
    extern void qt_x11_set_global_double_buffer(bool);
    qt_x11_set_global_double_buffer(false);
    ...

See also:

event(), repaint(), update(), QPainter, QPixmap, QPaintEvent, {Analog Clock Example}

Reimplemented from QWidget.

int PuzzleWidget::findPiece

(

const QRect &

pieceRect

)

const [private]

const QRect PuzzleWidget::targetSquare

(

const QPoint &

position

)

const [private]

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Member Data Documentation

QList<QPixmap> PuzzleWidget::piecePixmaps [private]

Definition at line 59 of file puzzlewidget.h.

Referenced by clear(), dropEvent(), mousePressEvent(), and paintEvent().

QList<QRect> PuzzleWidget::pieceRects [private]

Definition at line 60 of file puzzlewidget.h.

Referenced by clear(), dropEvent(), findPiece(), mousePressEvent(), and paintEvent().

QList<QPoint> PuzzleWidget::pieceLocations [private]

Definition at line 61 of file puzzlewidget.h.

Referenced by clear(), dropEvent(), and mousePressEvent().

QRect PuzzleWidget::highlightedRect [private]

Definition at line 62 of file puzzlewidget.h.

Referenced by clear(), dragLeaveEvent(), dragMoveEvent(), dropEvent(), and paintEvent().

int PuzzleWidget::inPlace [private]

Definition at line 63 of file puzzlewidget.h.

Referenced by clear(), dropEvent(), and mousePressEvent().

QList<QPixmap> PuzzleWidget::piecePixmaps [private]

Definition at line 59 of file puzzlewidget.h.

QList<QRect> PuzzleWidget::pieceRects [private]

Definition at line 60 of file puzzlewidget.h.

QList<QPoint> PuzzleWidget::pieceLocations [private]

Definition at line 61 of file puzzlewidget.h.

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The documentation for this class was generated from the following files:

• examples/draganddrop/puzzle/puzzlewidget.h
• examples/itemviews/puzzle/puzzlewidget.h
• examples/draganddrop/puzzle/puzzlewidget.cpp
• examples/itemviews/puzzle/puzzlewidget.cpp

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