Color¶

Kirigami has a color palette that follow the system colors, to better integrate on the platform it’s running in, for instance Plasma Desktop, Plasma Mobile, GNOME or Android.

All the default controls available as QML comoponents provided by Kirigami and all the components available in the QtQuickControls2 QML plugin will already follow this palette by default, so usually no custom coloring should be needed at all for those controls.

Primitive components such as Rectangle should always be colored with the color palette provided by Kirigami via the Theme attached property.

Hardcoded colors in QML, such as #32b2fa or red should usually be avoided; if it’s really necessary to have elements with custom colors, it should be an area where only custom colors are used (usually in the content area of the app, and never in the crome such as toolbars or dialogs), for instance an hardcoded “black” foreground can’t be used over a Kirigami.Theme.backgroundColor background, because if the platform uses a dark color scheme the result will bea poor contrasting black over almost black.

Theme¶

For more information about the Kirigami Thmeme class, see the API docs.

Kirigami.Theme is an attached property, therefore is available to use in any QML item, it contains as properties all the colors available in the palette, and what palette to use, as the colorSet property.

Example:

import QtQuick 2.11
import org.kde kirigami 2.9 as Kirigami

...
Rectangle {
    ...
    color: Kirigami.Theme.backgroundColor
}

[TODO]: screenshot of a qml file with an annotated UI showing all the available color

Color Set¶

Depending where a control is, it should use a different color set: for instance, (with the Breeze light color theme) in itemviews, the normal background is almost white, while in other regions, such as toolbars or dialogs, the normal background color is gray.

If you set a color set for an item, all of child items (as well as granchildren and so on) will inherit it automatically (unless the property inherit has explicitly been set to false, which should always be done when the developer wants to force a specific color set) so it’s easy to change colors for an entire hierarchy if items without touching any of the items themselves.

Kirigami.Theme supports 5 different color sets:

View: Color set for item views, usually the lightest of all (in light color themes)
Window: Default Color set for windows and “chrome” areas
Button: Color set used by buttons
Selection: Color set used by selectged areas
Tooltip: Color set used by tooltips
Complementary: Color set meant to be complementary to Window: usually is dark even in light themes. may be used for “emphasis” in small areas of the application

Example:

import QtQuick 2.11
import QtQuick.Controls 2.2 as Controls
import org.kde kirigami 2.9 as Kirigami

// The comments assume the system uses the Breeze Light color theme
...
Rectangle {
    // A gray color will be used, as the default color set is Window
    color: Kirigami.Theme.backgroundColor

    Controls.Label {
        // The text will be near-black, as is defined in the Window
        // color set
        text: i18n("hello")
    }

    Rectangle {
        ...
        // Use the set for ItemViews
        Kirigami.Theme.colorSet: Kirigami.Theme.View

        // Don't inherit from the parent
        Kirigami.Theme.inherit: false

        // This will be a near-white color
        color: Kirigami.Theme.backgroundColor

        Rectangle {
            ...
            // This will be a near-white color too, as the colorSet
            // is inherited from the parent and will be View
            color: Kirigami.Theme.backgroundColor

            Controls.Label {
                // The text will be near-black, as is defined in the View
                // color set
                text: i18n("hello")
            }
        }
        Rectangle {
            ...
            // Use the Complementary set
            Kirigami.Theme.colorSet: Kirigami.Theme.Complementary

            // Don't inherit from the parent
            Kirigami.Theme.inherit: false

            // This will be near-black as in the Complementary color set
            // the background color is dark.
            color: Kirigami.Theme.backgroundColor

            Controls.Label {
                // The text will be near-white, as is defined in the
                // Complementary color set
                text: i18n("hello")
            }
        }
    }
}

Some components such as Labels will automatically inherit by default the color set, some other components have a fixed color set, for instance Buttons are fixed to the Button color set. If is desired for the button to inherit the parent color set, the inherit property should be explicitly set to true:

import QtQuick 2.11
import QtQuick.Controls 2.2 as Controls
import org.kde kirigami 2.9 as Kirigami

...
Controls.Button {
    Kirigami.Theme.inherit: true
    text: i18n("ok")
}

[TODO]: screenshot of a comparison between a button that inherits and one that doesn’t

Using Custom Colors¶

Altough is discouraged to use hardcoded colors, Kirigami offers a more maintainable way to assign a custom hardcoded palette to an item and all its children, that will allow to define such custom colors in one place and one only:

import QtQuick 2.11
import QtQuick.Controls 2.2 as Controls
import org.kde kirigami 2.9 as Kirigami

Rectangle {
    Kirigami.Theme.inherit: false
    // NOTE: regardless of the color set used, it's recommended to replace
    // all available colors in Theme, to avoid badly contrasting colors
    Kirigami.Theme.colorSet: Kirigami.Theme.Window
    Kirigami.Theme.backgroundColor: "#b9d795"
    Kirigami.Theme.textColor: "#465c2b"
    Kirigami.Theme.highlightColor: "#89e51c"
    ... // Redefine all the others

    // This will be "#b9d795"
    color: Kirigami.Theme.backgroundColor

    Rectangle {
        // This will be "#465c2b"
        color: Kirigami.Theme.textColor
    }
}

[TODO] Screenshot