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This article mainly introduces "how to use C++ Qt QColorDialog". In daily operation, I believe many people have doubts about how to use C++ Qt QColorDialog. The editor consulted all kinds of materials and sorted out simple and easy-to-use methods of operation. I hope it will be helpful to answer the doubts about "how to use C++ Qt QColorDialog". Next, please follow the editor to study!

Qt provides a color selection box, as shown below:

How to use QColorDialog

For example, in the following code, click the button to pop up the color selection box, select the color, and change the background color of the QLabel.

# include "widget.h" # include "ui_widget.h" # include # include Widget::Widget (QWidget * parent): QWidget (parent), ui (new Ui::Widget) {ui- > setupUi (this); ui- > label- > setText (U8 "I am lable");} Widget::~Widget () {delete ui;} void Widget::on_btn1_clicked () {QColor color = QColorDialog::getColor (Qt::white, this, U8 "Select Color") If (color.isValid ()) {QPalette palette; palette.setColor (QPalette::Background, color); ui- > label- > setAutoFillBackground (true); ui- > label- > setPalette (palette);}}

The effect is as follows:

The call of getColor

GetColor declares as follows:

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

The first parameter is the default color. For example, I directly set it to white in the above code.

The second parameter is the parent window pointer

The third is the color dialog window title.

QPalette setColor

SetColor's statement is as follows:

Inline void QPalette::setColor (ColorRole acr, const QColor & acolor)

You can use the color returned by QColorDialog to construct QPalette directly. Note that the first parameter of setColor requires a ColorRole, as described below:

Enum ColorRole {WindowText, Button, Light, Midlight, Dark, Mid, Text, BrightText, ButtonText, Base, Window, Shadow, Highlight, HighlightedText, Link, LinkVisited, AlternateBase, NoRole, ToolTipBase, ToolTipText, PlaceholderText, NColorRoles = PlaceholderText + 1 # if QT_DEPRECATED_SINCE (5,13) Foreground Q_DECL_ENUMERATOR_DEPRECATED_X ("Use QPalette::WindowText instead") = WindowText, Background Q_DECL_ENUMERATOR_DEPRECATED_X ("Use QPalette::Window instead") = Window#endif}

For example, the above code is to change the background color of Label, then you need to use Background enumeration body, if you change the text, use Text.

At this point, the study on "how to use C++ Qt QColorDialog" is over. I hope I can solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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