QDropEvent Class Reference

The QDropEvent class provides an event which is sent when a drag and drop action is completed. More...

#include <qevent.h>

Inheritance diagram for QDropEvent:

Public Functions
void	acceptProposedAction ()
	Sets the drop action to be the proposed action. More...
Qt::DropAction	dropAction () const
	Returns the action to be performed on the data by the target. More...
QByteArray	encodedData (const char *) const
	Returns a byte array containing the drag's data, in format. More...
const char *	format (int n=0) const
	Returns a string describing one of the available data types for this drag. More...
Qt::KeyboardModifiers	keyboardModifiers () const
	Returns the modifier keys that are pressed. More...
const QMimeData *	mimeData () const
	Returns the data that was dropped on the widget and its associated MIME type information. More...
Qt::MouseButtons	mouseButtons () const
	Returns the mouse buttons that are pressed. More...
const QPoint &	pos () const
	Returns the position where the drop was made. More...
Qt::DropActions	possibleActions () const
	Returns an OR-combination of possible drop actions. More...
Qt::DropAction	proposedAction () const
	Returns the proposed drop action. More...
bool	provides (const char *) const
	Returns true if this event provides format mimeType; otherwise returns false. More...
	QDropEvent (const QPoint &pos, Qt::DropActions actions, const QMimeData *data, Qt::MouseButtons buttons, Qt::KeyboardModifiers modifiers, Type type=Drop)
	Constructs a drop event of a certain type corresponding to a drop at the point specified by pos in the destination widget's coordinate system. More...
void	setDropAction (Qt::DropAction action)
	Sets the action to be performed on the data by the target. More...
QWidget *	source () const
	If the source of the drag operation is a widget in this application, this function returns that source; otherwise it returns 0. More...
	~QDropEvent ()
Public Functions inherited from QEvent
void	accept ()
	Sets the accept flag of the event object, the equivalent of calling setAccepted(true). More...
void	ignore ()
	Clears the accept flag parameter of the event object, the equivalent of calling setAccepted(false). More...
bool	isAccepted () const
	QEvent (Type type)
	Contructs an event object of type type. More...
void	setAccepted (bool accepted)
bool	spontaneous () const
	Returns true if the event originated outside the application (a system event); otherwise returns false. More...
Type	type () const
	Returns the event type. More...
virtual	~QEvent ()
	Destroys the event. More...
Public Functions inherited from QMimeSource
virtual	~QMimeSource ()
	Destroys the MIME source. More...

Protected Variables
Qt::DropActions	act
Qt::DropAction	default_action
Qt::DropAction	drop_action
QList< QByteArray >	fmts
const QMimeData *	mdata
Qt::KeyboardModifiers	modState
Qt::MouseButtons	mouseState
QPoint	p
Protected Variables inherited from QEvent
QEventPrivate *	d
ushort	t

Friends
class	QApplication

Additional Inherited Members
Public Types inherited from QEvent
enum	Type {   None = 0, Timer = 1, MouseButtonPress = 2, MouseButtonRelease = 3,   MouseButtonDblClick = 4, MouseMove = 5, KeyPress = 6, KeyRelease = 7,   FocusIn = 8, FocusOut = 9, Enter = 10, Leave = 11,   Paint = 12, Move = 13, Resize = 14, Create = 15,   Destroy = 16, Show = 17, Hide = 18, Close = 19,   Quit = 20, ParentChange = 21, ParentAboutToChange = 131, ThreadChange = 22,   WindowActivate = 24, WindowDeactivate = 25, ShowToParent = 26, HideToParent = 27,   Wheel = 31, WindowTitleChange = 33, WindowIconChange = 34, ApplicationWindowIconChange = 35,   ApplicationFontChange = 36, ApplicationLayoutDirectionChange = 37, ApplicationPaletteChange = 38, PaletteChange = 39,   Clipboard = 40, Speech = 42, MetaCall = 43, SockAct = 50,   WinEventAct = 132, DeferredDelete = 52, DragEnter = 60, DragMove = 61,   DragLeave = 62, Drop = 63, DragResponse = 64, ChildAdded = 68,   ChildPolished = 69, ChildRemoved = 71, ShowWindowRequest = 73, PolishRequest = 74,   Polish = 75, LayoutRequest = 76, UpdateRequest = 77, UpdateLater = 78,   EmbeddingControl = 79, ActivateControl = 80, DeactivateControl = 81, ContextMenu = 82,   InputMethod = 83, AccessibilityPrepare = 86, TabletMove = 87, LocaleChange = 88,   LanguageChange = 89, LayoutDirectionChange = 90, Style = 91, TabletPress = 92,   TabletRelease = 93, OkRequest = 94, HelpRequest = 95, IconDrag = 96,   FontChange = 97, EnabledChange = 98, ActivationChange = 99, StyleChange = 100,   IconTextChange = 101, ModifiedChange = 102, MouseTrackingChange = 109, WindowBlocked = 103,   WindowUnblocked = 104, WindowStateChange = 105, ToolTip = 110, WhatsThis = 111,   StatusTip = 112, ActionChanged = 113, ActionAdded = 114, ActionRemoved = 115,   FileOpen = 116, Shortcut = 117, ShortcutOverride = 51, WhatsThisClicked = 118,   ToolBarChange = 120, ApplicationActivate = 121, ApplicationActivated = ApplicationActivate, ApplicationDeactivate = 122,   ApplicationDeactivated = ApplicationDeactivate, QueryWhatsThis = 123, EnterWhatsThisMode = 124, LeaveWhatsThisMode = 125,   ZOrderChange = 126, HoverEnter = 127, HoverLeave = 128, HoverMove = 129,   AccessibilityHelp = 119, AccessibilityDescription = 130, AcceptDropsChange = 152, MenubarUpdated = 153,   ZeroTimerEvent = 154, GraphicsSceneMouseMove = 155, GraphicsSceneMousePress = 156, GraphicsSceneMouseRelease = 157,   GraphicsSceneMouseDoubleClick = 158, GraphicsSceneContextMenu = 159, GraphicsSceneHoverEnter = 160, GraphicsSceneHoverMove = 161,   GraphicsSceneHoverLeave = 162, GraphicsSceneHelp = 163, GraphicsSceneDragEnter = 164, GraphicsSceneDragMove = 165,   GraphicsSceneDragLeave = 166, GraphicsSceneDrop = 167, GraphicsSceneWheel = 168, KeyboardLayoutChange = 169,   DynamicPropertyChange = 170, TabletEnterProximity = 171, TabletLeaveProximity = 172, NonClientAreaMouseMove = 173,   NonClientAreaMouseButtonPress = 174, NonClientAreaMouseButtonRelease = 175, NonClientAreaMouseButtonDblClick = 176, MacSizeChange = 177,   ContentsRectChange = 178, MacGLWindowChange = 179, FutureCallOut = 180, GraphicsSceneResize = 181,   GraphicsSceneMove = 182, CursorChange = 183, ToolTipChange = 184, NetworkReplyUpdated = 185,   GrabMouse = 186, UngrabMouse = 187, GrabKeyboard = 188, UngrabKeyboard = 189,   MacGLClearDrawable = 191, StateMachineSignal = 192, StateMachineWrapped = 193, TouchBegin = 194,   TouchUpdate = 195, TouchEnd = 196, NativeGesture = 197, RequestSoftwareInputPanel = 199,   CloseSoftwareInputPanel = 200, UpdateSoftKeys = 201, WinIdChange = 203, Gesture = 198,   GestureOverride = 202, PlatformPanel = 212, User = 1000, MaxUser = 65535 }
	This enum type defines the valid event types in Qt. More...
Static Public Functions inherited from QEvent
static int	registerEventType (int hint=-1)
	Registers and returns a custom event type. More...

Detailed Description

The QDropEvent class provides an event which is sent when a drag and drop action is completed.

When a widget accepts drop events, it will receive this event if it has accepted the most recent QDragEnterEvent or QDragMoveEvent sent to it.

The drop event contains a proposed action, available from proposedAction(), for the widget to either accept or ignore. If the action can be handled by the widget, you should call the acceptProposedAction() function. Since the proposed action can be a combination of Qt::DropAction values, it may be useful to either select one of these values as a default action or ask the user to select their preferred action.

If the proposed drop action is not suitable, perhaps because your custom widget does not support that action, you can replace it with any of the possible drop actions by calling setDropAction() with your preferred action. If you set a value that is not present in the bitwise OR combination of values returned by possibleActions(), the default copy action will be used. Once a replacement drop action has been set, call accept() instead of acceptProposedAction() to complete the drop operation.

The mimeData() function provides the data dropped on the widget in a QMimeData object. This contains information about the MIME type of the data in addition to the data itself.

See also

QMimeData, QDrag, {Drag and Drop}

Definition at line 476 of file qevent.h.

Constructors and Destructors

QDropEvent()

QDropEvent::QDropEvent	(	const QPoint &	pos,
		Qt::DropActions	actions,
		const QMimeData *	data,
		Qt::MouseButtons	buttons,
		Qt::KeyboardModifiers	modifiers,
		Type	type = Drop
	)

Constructs a drop event of a certain type corresponding to a drop at the point specified by pos in the destination widget's coordinate system.

The actions indicate which types of drag and drop operation can be performed, and the drag data is stored as MIME-encoded data in data.

The states of the mouse buttons and keyboard modifiers at the time of the drop are specified by buttons and modifiers.

Definition at line 2645 of file qevent.cpp.

    : QEvent(type), p(pos), mouseState(buttons),
      modState(modifiers), act(actions),
      mdata(data)
{
    default_action = QDragManager::self()->defaultAction(act, modifiers);
    drop_action = default_action;
    ignore();
}

~QDropEvent()

QDropEvent::~QDropEvent

(

)

Warning

This function is not part of the public interface.

Definition at line 2657 of file qevent.cpp.

{
}

Functions

acceptProposedAction()

void QDropEvent::acceptProposedAction ( )

inline

Sets the drop action to be the proposed action.

See also

setDropAction(), proposedAction(), {QEvent::accept()}{accept()}

Definition at line 492 of file qevent.h.

Referenced by QLineEdit::dragMoveEvent(), QLineEdit::dropEvent(), and QTextControl::processEvent().

{ drop_action = default_action; accept(); }

dropAction()

Qt::DropAction QDropEvent::dropAction ( ) const

inline

Returns the action to be performed on the data by the target.

This may be different from the action supplied in proposedAction() if you have called setDropAction() to explicitly choose a drop action.

See also

setDropAction()

Definition at line 494 of file qevent.h.

Referenced by QAbstractItemViewPrivate::canDecode(), QOleDropTarget::DragOver(), QOleDropTarget::Drop(), QLineEdit::dropEvent(), handle_xdnd_position(), QX11Data::motifdndHandle(), QGraphicsViewPrivate::populateSceneDragDropEvent(), QTextControl::processEvent(), QOleDropTarget::sendDragEnterEvent(), and QX11Data::xdndHandleDrop().

{ return drop_action; }

encodedData()

QByteArray QDropEvent::encodedData ( const char *  format ) const

virtual

Returns a byte array containing the drag's data, in format.

data() normally needs to get the data from the drag source, which is potentially very slow, so it's advisable to call this function only if you're sure that you will need the data in that particular format.

The resulting data will have a size of 0 if the format was not available.

See also

format() QByteArray::size()

Implements QMimeSource.

Definition at line 2679 of file qevent.cpp.

{
    return mdata->data(QLatin1String(format));
}

format()

const char * QDropEvent::format ( int  n = 0 ) const

virtual

Returns a string describing one of the available data types for this drag.

Common examples are "text/plain" and "image/gif". If n is less than zero or greater than the number of available data types, format() returns 0.

This function is provided mainly for debugging. Most drop targets will use provides().

See also

data() provides()

Implements QMimeSource.

Definition at line 2700 of file qevent.cpp.

{
    if (fmts.isEmpty()) {
        QStringList formats = mdata->formats();
        for (int i = 0; i < formats.size(); ++i)
            fmts.append(formats.at(i).toLatin1());
    }
    if (n < 0 || n >= fmts.size())
        return 0;
    return fmts.at(n).constData();
}

keyboardModifiers()

Qt::KeyboardModifiers QDropEvent::keyboardModifiers ( ) const

inline

Returns the modifier keys that are pressed.

Definition at line 488 of file qevent.h.

Referenced by QOleDropTarget::DragOver(), QApplication::notify(), and QGraphicsViewPrivate::populateSceneDragDropEvent().

{ return modState; }

mimeData()

const QMimeData * QDropEvent::mimeData ( ) const

inline

Returns the data that was dropped on the widget and its associated MIME type information.

Definition at line 498 of file qevent.h.

Referenced by QAbstractItemViewPrivate::canDecode(), QUrlModel::canDrop(), QColorWell::dragEnterEvent(), QColorShowLabel::dragEnterEvent(), QLineEdit::dragMoveEvent(), QColorWell::dragMoveEvent(), QLineEdit::dropEvent(), QAbstractItemView::dropEvent(), QColorWell::dropEvent(), QColorShowLabel::dropEvent(), QApplication::notify(), QGraphicsViewPrivate::populateSceneDragDropEvent(), and QTextControl::processEvent().

{ return mdata; }

mouseButtons()

Qt::MouseButtons QDropEvent::mouseButtons ( ) const

inline

Returns the mouse buttons that are pressed.

Definition at line 487 of file qevent.h.

Referenced by QApplication::notify(), and QGraphicsViewPrivate::populateSceneDragDropEvent().

{ return mouseState; }

pos()

const QPoint & QDropEvent::pos ( ) const

inline

Returns the position where the drop was made.

Definition at line 486 of file qevent.h.

Referenced by QLineEdit::dragMoveEvent(), QListModeViewBase::dragMoveEvent(), QPlainTextEdit::dragMoveEvent(), QTextEdit::dragMoveEvent(), QAbstractItemView::dragMoveEvent(), QColorWell::dragMoveEvent(), QLineEdit::dropEvent(), QColorWell::dropEvent(), QAbstractItemViewPrivate::dropOn(), QListModeViewBase::dropOn(), QIconModeViewBase::filterDragMoveEvent(), QIconModeViewBase::filterDropEvent(), QApplication::notify(), QGraphicsViewPrivate::populateSceneDragDropEvent(), and QTextControl::processEvent().

{ return p; }

possibleActions()

Qt::DropActions QDropEvent::possibleActions ( ) const

inline

Returns an OR-combination of possible drop actions.

See also

dropAction()

Definition at line 490 of file qevent.h.

Referenced by QApplication::notify(), and QGraphicsViewPrivate::populateSceneDragDropEvent().

{ return act; }

proposedAction()

Qt::DropAction QDropEvent::proposedAction ( ) const

inline

Returns the proposed drop action.

See also

dropAction()

Definition at line 491 of file qevent.h.

Referenced by QGraphicsViewPrivate::populateSceneDragDropEvent().

{ return default_action; }

provides()

bool QDropEvent::provides ( const char *  mimeType ) const

virtual

Returns true if this event provides format mimeType; otherwise returns false.

See also

data()

Reimplemented from QMimeSource.

Definition at line 2723 of file qevent.cpp.

{
    return mdata->formats().contains(QLatin1String(mimeType));
}

setDropAction()

void QDropEvent::setDropAction

(

Qt::DropAction

action

)

Sets the action to be performed on the data by the target.

Use this to override the proposed action with one of the possible actions.

If you set a drop action that is not one of the possible actions, the drag and drop operation will default to a copy operation.

Once you have supplied a replacement drop action, call accept() instead of acceptProposedAction().

See also

dropAction()

Definition at line 2746 of file qevent.cpp.

Referenced by QGraphicsProxyWidget::dragMoveEvent(), QGraphicsView::dragMoveEvent(), QOleDropTarget::DragOver(), QOleDropTarget::Drop(), QGraphicsView::dropEvent(), QAbstractItemView::dropEvent(), handle_xdnd_position(), QX11Data::motifdndHandle(), and QOleDropTarget::sendDragEnterEvent().

{
    if (!(action & act) && action != Qt::IgnoreAction)
        action = default_action;
    drop_action = action;
}

source()

QWidget * QDropEvent::source

(

)

const

If the source of the drag operation is a widget in this application, this function returns that source; otherwise it returns 0.

The source of the operation is the first parameter to the QDrag object used instantiate the drag.

This is useful if your widget needs special behavior when dragging to itself.

See also

QDrag::QDrag()

Definition at line 2739 of file qevent.cpp.

Referenced by QAbstractItemView::dragEnterEvent(), QAbstractItemView::dragMoveEvent(), QLineEdit::dropEvent(), QListWidget::dropEvent(), QTableWidget::dropEvent(), QAbstractItemView::dropEvent(), QTreeWidget::dropEvent(), QAbstractItemViewPrivate::droppingOnItself(), QIconModeViewBase::filterDragMoveEvent(), QIconModeViewBase::filterDropEvent(), QGraphicsViewPrivate::populateSceneDragDropEvent(), and QTextControl::processEvent().

{
    QDragManager *manager = QDragManager::self();
    return manager ? manager->source() : 0;
}

Friends and Related Functions

QApplication

friend class QApplication

friend

Definition at line 518 of file qevent.h.

Properties

act

Qt::DropActions QDropEvent::act

protected

Definition at line 522 of file qevent.h.

Referenced by QDropEvent(), and setDropAction().

default_action

Qt::DropAction QDropEvent::default_action

protected

Definition at line 524 of file qevent.h.

Referenced by QDropEvent(), and setDropAction().

drop_action

Qt::DropAction QDropEvent::drop_action

protected

Definition at line 523 of file qevent.h.

Referenced by QDropEvent(), and setDropAction().

fmts

QList<QByteArray> QDropEvent::fmts

mutableprotected

Definition at line 526 of file qevent.h.

Referenced by format().

mdata

const QMimeData* QDropEvent::mdata

protected

Definition at line 525 of file qevent.h.

Referenced by encodedData(), format(), and provides().

modState

Qt::KeyboardModifiers QDropEvent::modState

protected

Definition at line 521 of file qevent.h.

mouseState

Qt::MouseButtons QDropEvent::mouseState

protected

Definition at line 520 of file qevent.h.

p

QPoint QDropEvent::p

protected

Definition at line 519 of file qevent.h.

Referenced by QApplication::notify().

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

• /src/gui/kernel/qevent.h
• /src/gui/kernel/qevent.cpp