B4J Tutorial [BANano] How to detect if your device browser is in Dark / Light Theme Mode

Hi Fam

I want to detect if my device browser is in dark/ light mode and apply some settings on my app.

So here we go, we have 2 methods, one to fire each time the web browser mode is changed, and another to return the mode.

1. Detect Dark / Light Theme changes.

Dim cbTheme As Object = Banano.CallBack(mCallBack, "DarkTheme", Null)
        Dim matchMedia As BANanoObject = Banano.Window.RunMethod("matchMedia", "(prefers-color-scheme: dark)")
        matchMedia.AddEventListener("change", cbTheme, True)        'ignore

So this calls the DarkTheme callback each time the website dark theme is toggled.

2. Return true if dark mode is true.

'return if the browser is in dark mode
Sub IsDarkMode As Boolean
    Dim matchMedia As BANanoObject = Banano.Window.RunMethod("matchMedia", "(prefers-color-scheme: dark)")
    Dim res As Boolean = matchMedia.GetField("matches").result
    Return res
End Sub

Enjoy!