QwtCachePanner provides panning of a widget 更多...

#include <qwt_cache_panner.h>

类 QwtCachePanner 继承关系图:

类
class	PrivateData

信号
void	panned (int dx, int dy)
	Signal emitted when panning is done

void	moved (int dx, int dy)
	Signal emitted while the widget moved, but panning is not finished

Public 成员函数
	QwtCachePanner (QWidget *parent)
	Creates a panner that is enabled for the left mouse button

void	setEnabled (bool)
	En/disable the panner

bool	isEnabled () const
	Return whether the panner is enabled

void	setMouseButton (Qt::MouseButton, Qt::KeyboardModifiers=Qt::NoModifier)
	Change the mouse button and modifiers used for panning

void	getMouseButton (Qt::MouseButton &button, Qt::KeyboardModifiers &) const
	Get mouse button and modifiers used for panning

void	setAbortKey (int key, Qt::KeyboardModifiers=Qt::NoModifier)
	Change the abort key

void	getAbortKey (int &key, Qt::KeyboardModifiers &) const
	Get the abort key and modifiers

void	setCursor (const QCursor &)
	Change the cursor that is active while panning

const QCursor	cursor () const
	Return the cursor that is active while panning

void	setOrientations (Qt::Orientations)
	Set the orientations where panning is enabled

Qt::Orientations	orientations () const
	Return the orientation where panning is enabled

bool	isOrientationEnabled (Qt::Orientation) const
	Check if an orientation is enabled

virtual bool	eventFilter (QObject , QEvent ) override
	Event filter

Protected 成员函数
virtual void	widgetMousePressEvent (QMouseEvent *)
	Handle a mouse press event for the observed widget.

virtual void	widgetMouseReleaseEvent (QMouseEvent *)
	Handle a mouse release event for the observed widget.

virtual void	widgetMouseMoveEvent (QMouseEvent *)
	Handle a mouse move event for the observed widget.

virtual void	widgetKeyPressEvent (QKeyEvent *)
	Handle a key press event for the observed widget.

virtual void	widgetKeyReleaseEvent (QKeyEvent *)
	Handle a key release event for the observed widget.

virtual void	paintEvent (QPaintEvent *) override
	Paint event

virtual QBitmap	contentsMask () const
	Calculate a mask for the contents of the panned widget

virtual QPixmap	grab () const
	Grab the widget into a pixmap

详细描述

QwtCachePanner provides panning of a widget

QwtCachePanner grabs the contents of a widget, that can be dragged in all directions. The offset between the start and the end position is emitted by the panned signal. QwtCachePanner grabs the content of the widget into a pixmap and moves the pixmap around, without initiating any repaint events for the widget. Areas, that are not part of content are not painted while panning. This makes panning fast enough for widgets, where repaints are too slow for mouse movements. For widgets, where repaints are very fast it might be better to implement panning manually by mapping mouse events into paint events.

构造及析构函数说明

◆ QwtCachePanner()

QwtCachePanner::QwtCachePanner ( QWidget * parent )

explicit

Creates a panner that is enabled for the left mouse button

参数

[in] parent Parent widget to be panned

Destructor

成员函数说明

◆ contentsMask()

QBitmap QwtCachePanner::contentsMask ( ) const

protectedvirtual

Calculate a mask for the contents of the panned widget

Sometimes only parts of the contents of a widget should be panned. F.e. for a widget with a styled background with rounded borders only the area inside of the border should be panned.

返回: An empty bitmap, indicating no mask

被 QwtPlotCachePanner 重载.

◆ cursor()

const QCursor QwtCachePanner::cursor ( ) const

Return the cursor that is active while panning

返回: Cursor active while panning

参见: setCursor()

◆ eventFilter()

bool QwtCachePanner::eventFilter	(	QObject *	object,
		QEvent *	event
	)

overridevirtual

Event filter

When isEnabled() is true mouse events of the observed widget are filtered.

参数

[in]	object	Object to be filtered
[in]	event	Event

返回: Always false, beside for paint events for the parent widget

参见: widgetMousePressEvent(), widgetMouseReleaseEvent(), widgetMouseMoveEvent()

◆ getAbortKey()

void QwtCachePanner::getAbortKey	(	int &	key,
		Qt::KeyboardModifiers &	modifiers
	)		const

Get the abort key and modifiers

参数

[out]	key	Key code used for abort
[out]	modifiers	Keyboard modifiers used for abort

◆ getMouseButton()

void QwtCachePanner::getMouseButton	(	Qt::MouseButton &	button,
		Qt::KeyboardModifiers &	modifiers
	)		const

Get mouse button and modifiers used for panning

参数

[out]	button	Mouse button used for panning
[out]	modifiers	Keyboard modifiers used for panning

◆ grab()

QPixmap QwtCachePanner::grab ( ) const

protectedvirtual

Grab the widget into a pixmap

返回: Grabbed pixmap

被 QwtPlotCachePanner 重载.

◆ isEnabled()

bool QwtCachePanner::isEnabled ( ) const

Return whether the panner is enabled

返回: true when enabled, false otherwise

参见: setEnabled(), eventFilter()

◆ isOrientationEnabled()

bool QwtCachePanner::isOrientationEnabled ( Qt::Orientation o ) const

Check if an orientation is enabled

参数

[in] o Orientation to check

返回: True if the orientation is enabled

参见: orientations(), setOrientations()

◆ moved

void QwtCachePanner::moved	(	int	dx,
		int	dy
	)

signal

Signal emitted while the widget moved, but panning is not finished

参数

[in]	dx	Offset in horizontal direction
[in]	dy	Offset in vertical direction

◆ orientations()

Qt::Orientations QwtCachePanner::orientations ( ) const

Return the orientation where panning is enabled

返回: Orientation flags

◆ paintEvent()

void QwtCachePanner::paintEvent ( QPaintEvent * event )

overrideprotectedvirtual

Paint event

Repaint the grabbed pixmap on its current position and fill the empty spaces by the background of the parent widget.

参数

[in] event Paint event

◆ panned

void QwtCachePanner::panned	(	int	dx,
		int	dy
	)

signal

Signal emitted when panning is done

参数

[in]	dx	Offset in horizontal direction
[in]	dy	Offset in vertical direction

◆ setAbortKey()

void QwtCachePanner::setAbortKey	(	int	key,
		Qt::KeyboardModifiers	modifiers = `Qt::NoModifier`
	)

Change the abort key

The defaults are Qt::Key_Escape and Qt::NoModifiers

参数

[in]	key	Key code (See Qt::Keycode)
[in]	modifiers	Keyboard modifiers

◆ setCursor()

void QwtCachePanner::setCursor ( const QCursor & cursor )

Change the cursor that is active while panning

The default is the cursor of the parent widget.

参数

[in] cursor New cursor

参见: setCursor()

◆ setEnabled()

void QwtCachePanner::setEnabled ( bool on )

En/disable the panner

When enabled is true an event filter is installed for the observed widget, otherwise the event filter is removed.

参数

[in] on true or false

参见: isEnabled(), eventFilter()

◆ setMouseButton()

void QwtCachePanner::setMouseButton	(	Qt::MouseButton	button,
		Qt::KeyboardModifiers	modifiers = `Qt::NoModifier`
	)

Change the mouse button and modifiers used for panning

The defaults are Qt::LeftButton and Qt::NoModifier

参数

[in]	button	Mouse button for panning
[in]	modifiers	Keyboard modifiers

◆ setOrientations()

void QwtCachePanner::setOrientations ( Qt::Orientations o )

Set the orientations where panning is enabled

The default value is in both directions: Qt::Horizontal | Qt::Vertical

参数

[in] o Orientation flags

◆ widgetKeyPressEvent()

void QwtCachePanner::widgetKeyPressEvent ( QKeyEvent * keyEvent )

protectedvirtual

Handle a key press event for the observed widget.

参数

keyEvent Key event

参见: eventFilter(), widgetKeyReleaseEvent()

◆ widgetKeyReleaseEvent()

void QwtCachePanner::widgetKeyReleaseEvent ( QKeyEvent * keyEvent )

protectedvirtual

Handle a key release event for the observed widget.

参数

keyEvent Key event

参见: eventFilter(), widgetKeyReleaseEvent()

◆ widgetMouseMoveEvent()

void QwtCachePanner::widgetMouseMoveEvent ( QMouseEvent * mouseEvent )

protectedvirtual

Handle a mouse move event for the observed widget.

参数

mouseEvent Mouse event

参见: eventFilter(), widgetMousePressEvent(), widgetMouseReleaseEvent()

◆ widgetMousePressEvent()

void QwtCachePanner::widgetMousePressEvent ( QMouseEvent * mouseEvent )

protectedvirtual

Handle a mouse press event for the observed widget.

参数

mouseEvent Mouse event

参见: eventFilter(), widgetMouseReleaseEvent(), widgetMouseMoveEvent(),

被 QwtPolarCachePanner 重载.

◆ widgetMouseReleaseEvent()

void QwtCachePanner::widgetMouseReleaseEvent ( QMouseEvent * mouseEvent )

protectedvirtual

Handle a mouse release event for the observed widget.

参数

mouseEvent Mouse event

参见: eventFilter(), widgetMousePressEvent(), widgetMouseMoveEvent(),

该类的文档由以下文件生成:

/home/runner/work/QWT/QWT/src/plot/qwt_cache_panner.h
/home/runner/work/QWT/QWT/src/plot/qwt_cache_panner.cpp

类

信号

Public 成员函数

Protected 成员函数

详细描述

构造及析构函数说明

◆ QwtCachePanner()

成员函数说明

◆ contentsMask()

◆ cursor()

◆ eventFilter()

◆ getAbortKey()

◆ getMouseButton()

◆ grab()

◆ isEnabled()

◆ isOrientationEnabled()

◆ moved

◆ orientations()

◆ paintEvent()

◆ panned

◆ setAbortKey()

◆ setCursor()

◆ setEnabled()

◆ setMouseButton()

◆ setOrientations()

◆ widgetKeyPressEvent()

◆ widgetKeyReleaseEvent()

◆ widgetMouseMoveEvent()

◆ widgetMousePressEvent()

◆ widgetMouseReleaseEvent()