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QColorDialog Class

The QColorDialog class provides a dialog widget for specifying colors. More...

Header: #include <QColorDialog>
qmake: QT += widgets
Inherits: QDialog

Public Types

enum ColorDialogOption { ShowAlphaChannel, NoButtons, DontUseNativeDialog }
flags ColorDialogOptions

Properties

Public Functions

QColorDialog(const QColor &initial, QWidget *parent = nullptr)
QColorDialog(QWidget *parent = nullptr)
virtual ~QColorDialog()
QColor currentColor() const
void open(QObject *receiver, const char *member)
QColorDialog::ColorDialogOptions options() const
QColor selectedColor() const
void setCurrentColor(const QColor &color)
void setOption(QColorDialog::ColorDialogOption option, bool on = true)
void setOptions(QColorDialog::ColorDialogOptions options)
bool testOption(QColorDialog::ColorDialogOption option) const

Reimplemented Public Functions

virtual void setVisible(bool visible) override

Signals

void colorSelected(const QColor &color)
void currentColorChanged(const QColor &color)

Static Public Members

QColor customColor(int index)
int customCount()
QColor getColor(const QColor &initial = Qt::white, QWidget *parent = nullptr, const QString &title = QString(), QColorDialog::ColorDialogOptions options = ColorDialogOptions())
void setCustomColor(int index, QColor color)
void setStandardColor(int index, QColor color)
QColor standardColor(int index)

Reimplemented Protected Functions

virtual void changeEvent(QEvent *e) override
virtual void done(int result) override

Detailed Description

The color dialog's function is to allow users to choose colors. For example, you might use this in a drawing program to allow the user to set the brush color.

The static functions provide modal color dialogs.

The static getColor() function shows the dialog, and allows the user to specify a color. This function can also be used to let users choose a color with a level of transparency: pass the ShowAlphaChannel option as an additional argument.

The user can store customCount() different custom colors. The custom colors are shared by all color dialogs, and remembered during the execution of the program. Use setCustomColor() to set the custom colors, and use customColor() to get them.

When pressing the "Pick Screen Color" button, the cursor changes to a haircross and the colors on the screen are scanned. The user can pick up one by clicking the mouse or the Enter button. Pressing Escape restores the last color selected before entering this mode.

The Standard Dialogs example shows how to use QColorDialog as well as other built-in Qt dialogs.

A color dialog in the Fusion widget style.

See also QColor, QFileDialog, QFontDialog, and Standard Dialogs Example.

Member Type Documentation

enum QColorDialog::ColorDialogOptionflags QColorDialog::ColorDialogOptions

This enum specifies various options that affect the look and feel of a color dialog.

Constant Value Description
QColorDialog::ShowAlphaChannel 0x00000001 Allow the user to select the alpha component of a color.
QColorDialog::NoButtons 0x00000002 Don't display OK and Cancel buttons. (Useful for "live dialogs".)
QColorDialog::DontUseNativeDialog 0x00000004 Use Qt's standard color dialog instead of the operating system native color dialog.

This enum was introduced or modified in Qt 4.5.

The ColorDialogOptions type is a typedef for QFlags<ColorDialogOption>. It stores an OR combination of ColorDialogOption values.

See also options, setOption(), testOption(), and windowModality().

Property Documentation

currentColor : QColor

This property holds the currently selected color in the dialog

Access functions:

QColor currentColor() const
void setCurrentColor(const QColor &color)

Notifier signal:

void currentColorChanged(const QColor &color)

options : ColorDialogOptions

This property holds the various options that affect the look and feel of the dialog

By default, all options are disabled.

Options should be set before showing the dialog. Setting them while the dialog is visible is not guaranteed to have an immediate effect on the dialog (depending on the option and on the platform).

Access functions:

QColorDialog::ColorDialogOptions options() const
void setOptions(QColorDialog::ColorDialogOptions options)

See also setOption() and testOption().

Member Function Documentation

QColorDialog::QColorDialog(const QColor &initial, QWidget *parent = nullptr)

Constructs a color dialog with the given parent and specified initial color.

This function was introduced in Qt 4.5.

QColorDialog::QColorDialog(QWidget *parent = nullptr)

Constructs a color dialog with the given parent.

This function was introduced in Qt 4.5.

[signal] void QColorDialog::colorSelected(const QColor &color)

This signal is emitted just after the user has clicked OK to select a color to use. The chosen color is specified by color.

See also color and currentColorChanged().

[signal] void QColorDialog::currentColorChanged(const QColor &color)

This signal is emitted whenever the current color changes in the dialog. The current color is specified by color.

Note: Notifier signal for property currentColor.

See also color and colorSelected().

[virtual] QColorDialog::~QColorDialog()

Destroys the color dialog.

[override virtual protected] void QColorDialog::changeEvent(QEvent *e)

Reimplements: QWidget::changeEvent(QEvent *event).

[static] QColor QColorDialog::customColor(int index)

Returns the custom color at the given index as a QColor value.

This function was introduced in Qt 4.5.

See also setCustomColor().

[static] int QColorDialog::customCount()

Returns the number of custom colors supported by QColorDialog. All color dialogs share the same custom colors.

[override virtual protected] void QColorDialog::done(int result)

Reimplements: QDialog::done(int r).

Closes the dialog and sets its result code to result. If this dialog is shown with exec(), done() causes the local event loop to finish, and exec() to return result.

See also QDialog::done().

[static] QColor QColorDialog::getColor(const QColor &initial = Qt::white, QWidget *parent = nullptr, const QString &title = QString(), QColorDialog::ColorDialogOptions options = ColorDialogOptions())

Pops up a modal color dialog with the given window title (or "Select Color" if none is specified), lets the user choose a color, and returns that color. The color is initially set to initial. The dialog is a child of parent. It returns an invalid (see QColor::isValid()) color if the user cancels the dialog.

The options argument allows you to customize the dialog.

This function was introduced in Qt 4.5.

void QColorDialog::open(QObject *receiver, const char *member)

Opens the dialog and connects its colorSelected() signal to the slot specified by receiver and member.

The signal will be disconnected from the slot when the dialog is closed.

This function was introduced in Qt 4.5.

QColor QColorDialog::selectedColor() const

Returns the color that the user selected by clicking the OK or equivalent button.

Note: This color is not always the same as the color held by the currentColor property since the user can choose different colors before finally selecting the one to use.

[static] void QColorDialog::setCustomColor(int index, QColor color)

Sets the custom color at index to the QColor color value.

Note: This function does not apply to the Native Color Dialog on the macOS platform. If you still require this function, use the QColorDialog::DontUseNativeDialog option.

See also customColor().

void QColorDialog::setOption(QColorDialog::ColorDialogOption option, bool on = true)

Sets the given option to be enabled if on is true; otherwise, clears the given option.

See also options and testOption().

[static] void QColorDialog::setStandardColor(int index, QColor color)

Sets the standard color at index to the QColor color value.

Note: This function does not apply to the Native Color Dialog on the macOS platform. If you still require this function, use the QColorDialog::DontUseNativeDialog option.

See also standardColor().

[override virtual] void QColorDialog::setVisible(bool visible)

Reimplements: QDialog::setVisible(bool visible).

Changes the visibility of the dialog. If visible is true, the dialog is shown; otherwise, it is hidden.

[static] QColor QColorDialog::standardColor(int index)

Returns the standard color at the given index as a QColor value.

This function was introduced in Qt 5.0.

See also setStandardColor().

bool QColorDialog::testOption(QColorDialog::ColorDialogOption option) const

Returns true if the given option is enabled; otherwise, returns false.

This function was introduced in Qt 4.5.

See also options and setOption().

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Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5.15/qcolordialog.html