Constants

Overview

Constants can be defined to replace any value with a selected type or to be used as special values.

The supported types are: - color - px - percentage - string - opa - bool

Usage

<consts>
        <color name="color1" value="0xff0000" help="Primary color"/>
        <px name="pad_xs" value="8" help="Small padding"/>
</consts>

Constants can be used in:

Style properties
Widget and component properties

And they can be used like this:

<styles>
        <style name="style1" bg_color="#color1"/>
</styles>

Variants

Constants support a <variant> attribute to change the constants at compile time. For example:

<consts>
        <px name="pad" value="8" help="General padding">
                <variant name="size" case="small" value="4"/>
                <variant name="size" case="large" value="12"/>
        </px>
</consts>

From which the following C code can be exported:

#if SIZE == SMALL
        #define PAD 4
#elif SIZE == LARGE
        #define PAD 12
#else
        #define PAD 8
#endif

Where SMALL and LARGE are just preprocessor defines with incremental values.