observable collection static resource in xaml c#

Question

I want to create an observable collection and bind it to itemsource of a combobox dropdown. I need to make this collection a resource (page/grid) to be able to bind to it inside a data template. Need help in defining a class structure . A sample class structure will really help. Collection is very simple, eg a list of all countries. Important requirement is that i should be able to add items to it. Basically a collection containing countries (string) that allows me to add items.

Answer 1

observable collection static resource in xaml c#

For this requirement, you could make custom ObservableCollection class in the code-behind, then implement it in the xaml.

For example:

public class CountrysObservableCollection : ObservableCollection<string>
{

    public CountrysObservableCollection()
    {

    }
}

Xaml

<Page.Resources>
    <local:CountrysObservableCollection x:Key="Countrys">
        <x:String>China</x:String>
        <x:String>USA</x:String>
        <x:String>Japan</x:String>
        <x:String>England</x:String>
        <x:String>Russia</x:String>
        <x:String>Korea</x:String>
        <x:String>Canada</x:String>
        <x:String>Australia</x:String>
    </local:CountrysObservableCollection>
</Page.Resources>

Usage

<ComboBox ItemsSource="{StaticResource Countrys}"/>

Update DataSource

private  void Button_Click(object sender, RoutedEventArgs e)
{
    var countrys = Resources["Countrys"] as ObservableCollection<string>;
    countrys.Add("New World");
}

update

<Application.Resources>
    <ResourceDictionary>
        <local:CountrysObservableCollection x:Key="Countrys">
            <x:String>China</x:String>
            <x:String>USA</x:String>
            <x:String>Japan</x:String>
            <x:String>England</x:String>
            <x:String>Russia</x:String>
            <x:String>Korea</x:String>
            <x:String>Canada</x:String>
            <x:String>Australia</x:String>
        </local:CountrysObservableCollection>
    </ResourceDictionary>
</Application.Resources>



 private  void Button_Click(object sender, RoutedEventArgs e)
 {
     var countrys = Application.Current.Resources["Countrys"]as ObservableCollection<string>;  
     countrys.Add("New World");
 }

Answer 2

There are a ton of examples on the web. Here is a simple one: Explain Combo Box Binding In MVVM - WPF