如何在Xamarin Forms中从ContentPage保存App.xaml中的资源？

Question

I have a Xamarin Forms App which needs theming, basically what i want is that when i open my app there is a toolbar which has a theme page and a theme page has some buttons, when i click on the button, it will change the background image of the entire app. The issue is when i close and re-opens the app, the image is not there.

Here is my App.xaml

    <ResourceDictionary>

        <!-- Styles -->
        <!-- Styles -->

    </ResourceDictionary>

</Application.Resources>

The code in the ContentPage button click

Application.Current.Resources.Add(new Xamarin.Forms.Style(typeof(ContentPage))
            {
                ApplyToDerivedTypes = true,
                Setters = {
                new Xamarin.Forms.Setter { Property = ContentPage.BackgroundImageProperty, Value = "Assets/bkg8.png"},
            }
            });

The code is working fine but the current style is not saving itself in App.xaml. I want it to be saved and load every time the app starts.

Thanks.

Answer 1

阅读有关动态资源的内容， https：//docs.microsoft.com/zh-cn/xamarin/xamarin-forms/user-interface/styles/xaml/dynamic

Answer 2

You can use Xamarin property storage to store your valuable and then change the resource on next startup.

https://docs.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/application-class#properties-dictionary