Use Case - Style And Theme Support
Styling with QML involves creating a visual type and binding that to a property or by directly assigning a value to a property. For types that incorporate Qt Quick's delegates the visual type attaches to the delegate property.
The SystemPalette type provides information about the system's palette information. QML applications can use this information to set the appearance of visual types to match the native look and feel. In addition, on desktop platforms, different color palettes are employed when changing states, for example, when the application loses keyboard focus.
When using the controls, the system colors are already used.