How to get current theme color ?

pamplemousse_mk2

Hello,

Is there a way to make my QML code be responsive to the colors of the current theme ?

import QtQuick 2.0
import QtQuick.Controls 2.0
import QtQuick.Controls.Material 2.12

Button {
  checkable: true
  autoExclusive: true

  Rectangle {
    width: 12
    height: width
    x: 0
    y: 5
    color: Material.accent
    border.color: "black"
    border.width: 1
    radius: width*0.5
  }
}

Here in my code, I used explicitly Material.accent to set the color of the rectangle, but if I change the theme, that value will be invalid. Is there a global property to get the current accent color, in example theme.accent or qtquicktheme.accent to make my code independant from the Material theme ? I can't find such information in the Qt documentation.

Regards.

SeeLook

Hi,

You might use SystemPalette:

SystemPalette {
    id: activePalette
    colorGroup: SystemPalette.Active
  }

then use it somewhere:
color: activePalette.highlight
or any of its property that suits your need.

But You won't find Windows accent color this way. To do so, some registry key has to be read:

Here is example how to change highlight color with Windows accent color and use it in application palette. (usually done in main.cpp before loading QML).

  QSettings accent(QStringLiteral("HKEY_USERS\\.DEFAULT\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Accent"),
                     QSettings::NativeFormat);
    if (accent.contains(QLatin1String("StartColorMenu"))) {
      int color = accent.value(QLatin1String("StartColorMenu")).toInt();
      int r = color & 0xff;
      int g = (color >> 8) & 0xff;
      int b = (color >> 16) & 0xff;
      auto pal = qApp->palette();
      QColor c(r, g, b);
      pal.setColor(QPalette::Active, QPalette::Highlight, c.lighter(150)); 
    // Accent color is quite strong , so here it is made lighter
      qApp->setPalette(pal);
    }

But how to get some system color under Android (if there is any) I even don't know.

pamplemousse_mk2

@SeeLook Hello, thank you for your answer. I will keep in mind SystemPalette for other use. Unfortunately, I work on Linux. Perhaps is there no solution and I must stick with Material.accent.

Regards.

SeeLook

Under Linux SystemPalete works out of the box.

RokeJulianLockhart

Under Linux, SystemPalete works out of the box.

@SeeLook, is it accessible from outside QML?

You won't find Windows accent color this way.

That seems strange. Does a JIRA FR for this exist?

QtTester

I think we need to write a function:
function accentColor()
{
if(theme == "Material")
return Material.accent;
else
return IOS.accent;
}

RokeJulianLockhart

@QtTester, by IOS, do you mean qt.io/blog/qt-quick-controls-2-ios-style? Regardless, post/744511 corroborates this.

SeeLook

Hi all,

Seems like all that above was cleared out with Qt 6. At least looking from Qt 6.9 point of view.
QGuiApplication::palette() keeps system colors either for Android and Windows now (I'm not able to confirm that for MacOS).
Which means either Windows accent color and Android (14+) accent color is QGuiApplication::palette() just out of the box.
The same with light/dark stuff. All is inside.
And this C++ QPalette is SystemPalette under QML.

Still, If one want to mess up with QML Material accent color, just add something like below to the main *.qml file:

import QtQuick.Controls.Material

// ...

SystemPalette {
    id: activePalette
    colorGroup: SystemPalette.Active
}
Material.accent: activePalette.highlight

And similar applies to Mac style, I guess.

QtTester

@SeeLook
Hi, i think you misunderstood the meaning. he just want to get a color from different style(material or ios), not from current windows's style.

RokeJulianLockhart

@QtTester, I think I'd misunderstood, too... Thanks.