Android Code Snippet Version safe themes

Update: If you are using B4A v8.0+ then you should just add:

CreateResourceFromFile(Macro, Themes.DarkTheme) 'or Themes.LightTheme

Older versions:
If you are not explicitly setting the theme in the manifest editor then it will change based on the device version and targetSdkVersion value.

Assuming that targetSdkVersion is set to 26 (as soon required by Google) then the theme used by default will be:

Device version

Android 2.x - Always the old Android 2.x theme
Android 4.x - Theme.Holo (dark background)
Android 5.x - 6.x - Theme.Material (dark background)
Android 7.x+ - Theme.Material.Light.DarkActionBar (light background)

This behavior can be problematic. In most cases it is better to explicitly set the theme. The correct way to set it is with manifest code such as:

Dark theme

SetApplicationAttribute(android:theme, "@style/DarkTheme")
CreateResource(values-v20, theme.xml,
<resources>
    <style
        name="DarkTheme" parent="@android:style/Theme.Material">
    </style>
</resources>
)
CreateResource(values-v14, theme.xml,
<resources>
    <style
        name="DarkTheme" parent="@android:style/Theme.Holo">
    </style>
</resources>
)

Light theme

SetApplicationAttribute(android:theme, "@style/LightTheme")
CreateResource(values-v20, theme.xml,
<resources>
    <style
        name="LightTheme" parent="@android:style/Theme.Material.Light">
    </style>
</resources>
)
CreateResource(values-v14, theme.xml,
<resources>
    <style
        name="LightTheme" parent="@android:style/Theme.Holo.Light">
    </style>
</resources>
)

 

[Jorge M A]

Sorry for the silly question, does the name of the resource, like "values-v20" or "values-v14", have some meaning? or are arbitrary names? thanks.

 

[Erel]

Yes. values-v14 will be used on API level 14+ and values-v20 will be used on API level 20+ (Android 5+).

 

[Multiverse app]

Can the above be used while using appcompact?

 

[Erel]

It is not needed when using AppCompat as AppCompat uses an explicit theme anyway.

If you want to change the colors with AppCompat: https://www.b4x.com/android/forum/threads/theme-colors.87716/#post-554897