QwtMagnifier(3)

💖 QwtMagnifier 💖

okay bestie, sit down, hydrate, and let's talk about the QwtMagnifier page from the Qwt User's Guide manual. She's a class, she zooms, she's lowkey iconic, and we're gonna go through every single line of her docs. no skimming. periodt. ✨

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🌸 NAME 🌸

QwtMagnifier — and that's literally it, the original just leaves a lil dash hanging there like a cliffhanger. No description, no vibes explained, just the name. We respect the mystery. 🫶

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🦋 SYNOPSIS 🦋

#include <qwt_magnifier.h>

Inherited by QwtPlotMagnifier. (yes, she has a whole sub-class, main character energy fr fr 👑)

👑 Public Member Functions

• QwtMagnifier (QWidget *)
• virtual ~QwtMagnifier ()
• virtual bool eventFilter (QObject *, QEvent *)
• void getMouseButton (int &button, int &buttonState) const
• void getZoomInKey (int &key, int &modifiers) const
• void getZoomOutKey (int &key, int &modifiers) const
• bool isEnabled () const
• double keyFactor () const
• double mouseFactor () const
• QWidget * parentWidget ()
• const QWidget * parentWidget () const
• void setEnabled (bool)
• void setKeyFactor (double)
• void setMouseButton (int button, int buttonState=Qt::NoButton)
• void setMouseFactor (double)
• void setWheelButtonState (int buttonState)
• void setWheelFactor (double)
• void setZoomInKey (int key, int modifiers)
• void setZoomOutKey (int key, int modifiers)
• int wheelButtonState () const
• double wheelFactor () const

🎀 Protected Member Functions

• virtual void rescale (double factor)=0
• virtual void widgetKeyPressEvent (QKeyEvent *)
• virtual void widgetKeyReleaseEvent (QKeyEvent *)
• virtual void widgetMouseMoveEvent (QMouseEvent *)
• virtual void widgetMousePressEvent (QMouseEvent *)
• virtual void widgetMouseReleaseEvent (QMouseEvent *)
• virtual void widgetWheelEvent (QWheelEvent *)

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✨ Detailed Description ✨

okay so here's the tea: QwtMagnifier provides zooming, by magnifying in steps. That's the whole bit. 💅

And using QwtMagnifier, a plot can be zoomed in/out in steps using keys, the mouse wheel, or by moving a mouse button in vertical direction. Three whole ways to zoom. Versatile queen. 🌈

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🍼 Constructor & Destructor Documentation 🍼

QwtMagnifier::QwtMagnifier (QWidget *parent) [explicit]

Constructor. She's born. 💖

Parameters:

• parent — Widget to be magnified

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🔥 Member Function Documentation 🔥

bool QwtMagnifier::eventFilter (QObject *o, QEvent *e) [virtual]

Event filter. When isEnabled() is true, the mouse events of the observed widget are filtered. 👀

See also: widgetMousePressEvent(), widgetMouseReleaseEvent(), widgetMouseMoveEvent(), widgetWheelEvent(), widgetKeyPressEvent() widgetKeyReleaseEvent()

void QwtMagnifier::getMouseButton (int &button, int &buttonState) const

No prose here bestie, just a pointer. 👉 See also: setMouseButton()

void QwtMagnifier::getZoomInKey (int &key, int &modifiers) const

See also: setZoomInKey()

void QwtMagnifier::getZoomOutKey (int &key, int &modifiers) const

See also: setZoomOutKey()

bool QwtMagnifier::isEnabled () const

Returns: true when enabled, false otherwise

See also: setEnabled(), eventFilter()

double QwtMagnifier::keyFactor () const

Returns: Key factor

See also: setKeyFactor()

double QwtMagnifier::mouseFactor () const

Returns: Mouse factor

See also: setMouseFactor()

QWidget * QwtMagnifier::parentWidget ()

Returns: Parent widget, where the rescaling happens

const QWidget * QwtMagnifier::parentWidget () const

Returns: Parent widget, where the rescaling happens

virtual void QwtMagnifier::rescale (double factor) [protected], [pure virtual]

Rescale the parent widget. It's pure virtual, so this one's a "you handle it, sub-class" situation. 🫡

Parameters:

• factor — Scale factor

Implemented in QwtPlotMagnifier.

void QwtMagnifier::setEnabled (bool on)

En/disable the magnifier. When enabled is true an event filter is installed for the observed widget, otherwise the event filter is removed. On and off, no in-between. 🔘

Parameters:

• on — true or false

See also: isEnabled(), eventFilter()

void QwtMagnifier::setKeyFactor (double factor)

Change the key factor. The key factor defines the ratio between the current range on the parent widget and the zoomed range for each key press of the zoom in/out keys. The default value is 0.9.

Parameters:

• factor — Key factor

See also: keyFactor(), setZoomInKey(), setZoomOutKey(), setWheelFactor, setMouseFactor()

void QwtMagnifier::setMouseButton (int button, int buttonState = Qt::NoButton)

Assign the mouse button that is used for zooming in/out. The default value is Qt::RightButton.

Parameters:

• button — Button
• buttonState — Button state

See also: getMouseButton()

void QwtMagnifier::setMouseFactor (double factor)

Change the mouse factor. The mouse factor defines the ratio between the current range on the parent widget and the zoomed range for each vertical mouse movement. The default value is 0.95.

Parameters:

• factor — Wheel factor

See also: mouseFactor(), setMouseButton(), setWheelFactor(), setKeyFactor()

void QwtMagnifier::setWheelButtonState (int buttonState)

Assign a mandatory button state for zooming in/out using the wheel. The default button state is Qt::NoButton. Like, the wheel must have this state. Mandatory. She said what she said. 💅

Parameters:

• buttonState — Button state

See also: wheelButtonState()

void QwtMagnifier::setWheelFactor (double factor)

Change the wheel factor. The wheel factor defines the ratio between the current range on the parent widget and the zoomed range for each step of the wheel. The default value is 0.9.

Parameters:

• factor — Wheel factor

See also: wheelFactor(), setWheelButtonState(), setMouseFactor(), setKeyFactor()

void QwtMagnifier::setZoomInKey (int key, int modifiers)

Assign the key that is used for zooming in. The default combination is Qt::Key_Plus + Qt::NoModifier. ⭐

Parameters:

• key
• modifiers

See also: getZoomInKey(), setZoomOutKey()

void QwtMagnifier::setZoomOutKey (int key, int modifiers)

Assign the key that is used for zooming out. The default combination is Qt::Key_Minus + Qt::NoModifier.

Parameters:

• key
• modifiers

See also: getZoomOutKey(), setZoomOutKey()

not the See also section pointing at setZoomOutKey() from inside setZoomOutKey(). bestie is her own reference. we don't ask questions, we just reproduce it faithfully. 😭

int QwtMagnifier::wheelButtonState () const

Returns: Wheel button state

See also: setWheelButtonState()

double QwtMagnifier::wheelFactor () const

Returns: Wheel factor

See also: setWheelFactor()

void QwtMagnifier::widgetKeyPressEvent (QKeyEvent *ke) [protected], [virtual]

Handle a key press event for the observed widget. ⌨️

Parameters:

• ke — Key event

See also: eventFilter(), widgetKeyReleaseEvent()

void QwtMagnifier::widgetKeyReleaseEvent (QKeyEvent *) [protected], [virtual]

Handle a key release event for the observed widget. (yes, the See also points back at itself again — iconic, honestly 🎀)

Parameters:

• ke — Key event

See also: eventFilter(), widgetKeyReleaseEvent()

void QwtMagnifier::widgetMouseMoveEvent (QMouseEvent *me) [protected], [virtual]

Handle a mouse move event for the observed widget. 🖱️

Parameters:

• me — Mouse event

See also: eventFilter(), widgetMousePressEvent(), widgetMouseReleaseEvent(),

void QwtMagnifier::widgetMousePressEvent (QMouseEvent *me) [protected], [virtual]

Handle a mouse press event for the observed widget.

Parameters:

• me — Mouse event

See also: eventFilter(), widgetMouseReleaseEvent(), widgetMouseMoveEvent()

void QwtMagnifier::widgetMouseReleaseEvent (QMouseEvent *) [protected], [virtual]

Handle a mouse release event for the observed widget. (no Parameters block on this one, she keeps it minimal 💀)

See also: eventFilter(), widgetMousePressEvent(), widgetMouseMoveEvent(),

void QwtMagnifier::widgetWheelEvent (QWheelEvent *we) [protected], [virtual]

Handle a wheel event for the observed widget.

Parameters:

• we — Wheel event

See also: eventFilter()

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💜 Author 💜

Generated automatically by Doxygen for Qwt User's Guide from the source code. So like, a robot wrote this, and now a girl on the internet is translating it. Full circle. 🧚

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and that's the whole page bestie, no cap, we did not skip a single flag, default, param, or self-referential See also. 🌸

Version 5.2.3 — Tue Nov 20 2012 💖 stay zoomed in, stay magnified, mwah 💅✨