Applying Theme switch in MVVM

[Jonas Jsk]

I'm new to Xamarin Forms and I' trying to add a theme control to my application

I found this post - https://www.syncfusion.com/forums/147666/applying-theme-to-control

on how to (Applying theme to control), but the problem is that I want to know how to do this in MVVM

When I fallow the sample project in the link above and apply's the code to my project, I get the error

>>> "Severity Code Description Project File Line Suppression State Error CS0234 The type or namespace name 'MergedDictionaries' does not exist in the namespace 'CykelStaden.Resources' (are you missing an assembly reference?)"

This is my ViewModel

public class SettingsViewModel : BaseViewModel {private bool toggleTheme;private bool isLightTheme = true;
public bool ToggleTheme        {            get            {                return toggleTheme;            }            set            {                toggleTheme = value;                OnToggleTheme();            }        }private void OnToggleTheme()        {            if (isLightTheme)            {                ICollection<ResourceDictionary> mergedDictionaries = Resources.MergedDictionaries;                var lightTheme = mergedDictionaries.OfType<Themes.LightTheme>().FirstOrDefault();                if (lightTheme != null)                {                    mergedDictionaries.Remove(lightTheme);                }                mergedDictionaries.Add(new Themes.DarkTheme());                isLightTheme = false;            }            else            {                ICollection<ResourceDictionary> mergedDictionaries =   this.Resources.MergedDictionaries;                var darkTheme = mergedDictionaries.OfType<Themes.DarkTheme>().FirstOrDefault();                if (darkTheme != null)                {                    mergedDictionaries.Remove(darkTheme);                }                mergedDictionaries.Add(new Themes.LightTheme());                isLightTheme = true;            }        }}

How do I fix this please

Attachment: SettingsViewModel_6c53d39f.zip

[Jeya Kasipandi]

Hi Jonas,

Currently, we are validating on this and will update the details on November 11, 2021.We appreciate your patience until then.

Regards,
Jeya K

[Ruba Shanmugam]

Hi Jonas Jsk, 

 

Thanks for your patience. We have prepared a sample based on the provided code snippet. Can you get the sample link from below. 

 

Sample: https://www.syncfusion.com/downloads/support/directtrac/general/ze/Picker_Sample_SwitchThemesLightDark-1735825010 

 

Please let us know, if you have any other concerns. 

Regards, 

Ruba Shanmugam