Get font scaling factor to calculate the fontsize

I just found in the source code of Settings.System this function:

/** @hide */
public static void getConfigurationForUser(ContentResolver cr,
                                       Configuration outConfig, int userHandle) {
    outConfig.fontScale = Settings.System.getFloatForUser(
        cr, FONT_SCALE, outConfig.fontScale, userHandle);
    if (outConfig.fontScale < 0) {
        outConfig.fontScale = 1;
    }
}

There is however the FONT_SCALE in usage so I checked for that Configuration class where the documentation points to getResources().getConfiguration(). So I counld fix my code by using:

float scale = getResources().getConfiguration().fontScale;

Since my question was about to calculate the correct font size in pixel here is the way I use it nowerdays in Kotlin:

val Number.dpInPx: Int
    get() = TypedValue.applyDimension(
        TypedValue.COMPLEX_UNIT_DIP, toFloat(), Resources.getSystem().displayMetrics).toInt()

val Number.spInPx: Int
    get() = TypedValue.applyDimension(
        TypedValue.COMPLEX_UNIT_SP, toFloat(), Resources.getSystem().displayMetrics).toInt()

The usage is:

val textSize = 42.spInPx
val padding = 8.dpInPx

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