QGIS API Documentation  3.4.15-Madeira (e83d02e274)
Public Types | Public Slots | Signals | Public Member Functions | Static Public Member Functions | Protected Member Functions | Static Protected Member Functions | Protected Attributes | List of all members
QgsColorWidget Class Reference

A base class for interactive color widgets. More...

#include <qgscolorwidgets.h>

Inheritance diagram for QgsColorWidget:
Inheritance graph
[legend]

Public Types

enum  ColorComponent {
  Multiple = 0, Red, Green, Blue,
  Hue, Saturation, Value, Alpha
}
 Specifies the color component which the widget alters. More...
 

Public Slots

virtual void setColor (const QColor &color, bool emitSignals=false)
 Sets the color for the widget. More...
 
virtual void setComponent (QgsColorWidget::ColorComponent component)
 Sets the color component which the widget controls. More...
 
virtual void setComponentValue (int value)
 Alters the widget's color by setting the value for the widget's color component. More...
 

Signals

void colorChanged (const QColor &color)
 Emitted when the widget's color changes. More...
 
void hovered ()
 Emitted when mouse hovers over widget. More...
 

Public Member Functions

 QgsColorWidget (QWidget *parent=nullptr, ColorComponent component=Multiple)
 Construct a new color widget. More...
 
QColor color () const
 Returns the current color for the widget. More...
 
ColorComponent component () const
 Returns the color component which the widget controls. More...
 
int componentValue () const
 Returns the current value of the widget's color component. More...
 

Static Public Member Functions

static QPixmap createDragIcon (const QColor &color)
 Create an icon for dragging colors. More...
 

Protected Member Functions

void alterColor (QColor &color, QgsColorWidget::ColorComponent component, int newValue) const
 Alters a color by modifiying the value of a specific color component. More...
 
int componentRange () const
 Returns the range of valid values for the color widget's component. More...
 
int componentRange (ColorComponent component) const
 Returns the range of valid values a color component. More...
 
int componentValue (ColorComponent component) const
 Returns the value of a component of the widget's current color. More...
 
void dragEnterEvent (QDragEnterEvent *e) override
 
void dropEvent (QDropEvent *e) override
 
int hue () const
 Returns the hue for the widget. More...
 
void mouseMoveEvent (QMouseEvent *e) override
 
void mousePressEvent (QMouseEvent *e) override
 
void mouseReleaseEvent (QMouseEvent *e) override
 

Static Protected Member Functions

static const QPixmap & transparentBackground ()
 Generates a checkboard pattern pixmap for use as a background to transparent colors. More...
 

Protected Attributes

ColorComponent mComponent
 
QColor mCurrentColor
 
int mExplicitHue = 0
 QColor wipes the hue information when it is ambiguous (e.g., for saturation = 0). More...
 

Detailed Description

A base class for interactive color widgets.

Widgets can either allow setting a single component of a color (e.g., the red or green components), or an entire color. The QgsColorWidget also keeps track of any explicitly set hue for the color, so that this information is not lost when the widget is set to a color with an ambiguous hue (e.g., black or white shades).

Since
QGIS 2.5

Definition at line 39 of file qgscolorwidgets.h.

Member Enumeration Documentation

Specifies the color component which the widget alters.

Enumerator
Multiple 

Widget alters multiple color components.

Red 

Red component of color.

Green 

Green component of color.

Blue 

Blue component of color.

Hue 

Hue component of color (based on HSV model)

Saturation 

Saturation component of color (based on HSV model)

Value 

Value component of color (based on HSV model)

Alpha 

Alpha component (opacity) of color.

Definition at line 48 of file qgscolorwidgets.h.

Constructor & Destructor Documentation

QgsColorWidget::QgsColorWidget ( QWidget *  parent = nullptr,
ColorComponent  component = Multiple 
)

Construct a new color widget.

Parameters
parentparent QWidget for the widget
componentcolor component the widget alters

Definition at line 43 of file qgscolorwidgets.cpp.

Member Function Documentation

void QgsColorWidget::alterColor ( QColor &  color,
QgsColorWidget::ColorComponent  component,
int  newValue 
) const
protected

Alters a color by modifiying the value of a specific color component.

Parameters
colorcolor to alter
componentcolor component to alter
newValuenew value of color component. Values are automatically clipped to a valid range for the color component.

Definition at line 142 of file qgscolorwidgets.cpp.

QColor QgsColorWidget::color ( ) const

Returns the current color for the widget.

Returns
current widget color
See also
setColor

Definition at line 244 of file qgscolorwidgets.cpp.

void QgsColorWidget::colorChanged ( const QColor &  color)
signal

Emitted when the widget's color changes.

Parameters
colornew widget color
ColorComponent QgsColorWidget::component ( ) const
inline

Returns the color component which the widget controls.

Returns
color component for widget
See also
setComponent

Definition at line 79 of file qgscolorwidgets.h.

int QgsColorWidget::componentRange ( ) const
protected

Returns the range of valid values for the color widget's component.

Returns
maximum value allowed for color component, or -1 if widget has multiple components

Definition at line 105 of file qgscolorwidgets.cpp.

int QgsColorWidget::componentRange ( const QgsColorWidget::ColorComponent  component) const
protected

Returns the range of valid values a color component.

Returns
maximum value allowed for color component

Definition at line 110 of file qgscolorwidgets.cpp.

int QgsColorWidget::componentValue ( ) const

Returns the current value of the widget's color component.

Returns
value of color component, or -1 if widget has multiple components or an invalid color set
See also
setComponentValue
component

Definition at line 51 of file qgscolorwidgets.cpp.

int QgsColorWidget::componentValue ( const QgsColorWidget::ColorComponent  component) const
protected

Returns the value of a component of the widget's current color.

This method correctly handles hue values when the color has an ambiguous hue (e.g., black or white shades)

Parameters
componentcolor component to return
Returns
value of color component, or -1 if widget has an invalid color set
See also
hue

Definition at line 76 of file qgscolorwidgets.cpp.

QPixmap QgsColorWidget::createDragIcon ( const QColor &  color)
static

Create an icon for dragging colors.

Parameters
colorfor icon

Definition at line 56 of file qgscolorwidgets.cpp.

void QgsColorWidget::dragEnterEvent ( QDragEnterEvent *  e)
overrideprotected

Definition at line 188 of file qgscolorwidgets.cpp.

void QgsColorWidget::dropEvent ( QDropEvent *  e)
overrideprotected

Definition at line 201 of file qgscolorwidgets.cpp.

void QgsColorWidget::hovered ( )
signal

Emitted when mouse hovers over widget.

Since
QGIS 2.14
int QgsColorWidget::hue ( ) const
protected

Returns the hue for the widget.

This may differ from the hue for the QColor returned by color(), as QColor returns a hue of -1 if the color's hue is ambiguous (e.g., if the saturation is zero).

Returns
explicitly set hue for widget

Definition at line 130 of file qgscolorwidgets.cpp.

void QgsColorWidget::mouseMoveEvent ( QMouseEvent *  e)
overrideprotected

Definition at line 225 of file qgscolorwidgets.cpp.

void QgsColorWidget::mousePressEvent ( QMouseEvent *  e)
overrideprotected

Definition at line 232 of file qgscolorwidgets.cpp.

void QgsColorWidget::mouseReleaseEvent ( QMouseEvent *  e)
overrideprotected

Definition at line 238 of file qgscolorwidgets.cpp.

void QgsColorWidget::setColor ( const QColor &  color,
bool  emitSignals = false 
)
virtualslot

Sets the color for the widget.

Parameters
colorwidget color
emitSignalsset to true to emit the colorChanged signal after setting color
See also
color

Reimplemented in QgsColorTextWidget, and QgsColorSliderWidget.

Definition at line 342 of file qgscolorwidgets.cpp.

void QgsColorWidget::setComponent ( QgsColorWidget::ColorComponent  component)
virtualslot

Sets the color component which the widget controls.

Parameters
componentcolor component for widget
See also
component

Reimplemented in QgsColorSliderWidget, and QgsColorBox.

Definition at line 249 of file qgscolorwidgets.cpp.

void QgsColorWidget::setComponentValue ( int  value)
virtualslot

Alters the widget's color by setting the value for the widget's color component.

Parameters
valuevalue for widget's color component. This value is automatically clipped to the range of valid values for the color component.
See also
componentValue
setComponent
Note
this method has no effect if the widget is set to the QgsColorWidget::Multiple component

Reimplemented in QgsColorSliderWidget.

Definition at line 260 of file qgscolorwidgets.cpp.

const QPixmap & QgsColorWidget::transparentBackground ( )
staticprotected

Generates a checkboard pattern pixmap for use as a background to transparent colors.

Returns
checkerboard pixmap

Definition at line 178 of file qgscolorwidgets.cpp.

Member Data Documentation

ColorComponent QgsColorWidget::mComponent
protected

Definition at line 142 of file qgscolorwidgets.h.

QColor QgsColorWidget::mCurrentColor
protected

Definition at line 140 of file qgscolorwidgets.h.

int QgsColorWidget::mExplicitHue = 0
protected

QColor wipes the hue information when it is ambiguous (e.g., for saturation = 0).

So the hue is stored in mExplicit hue to keep it around, as it is useful when modifying colors

Definition at line 148 of file qgscolorwidgets.h.


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