如何获取Xamarin Forms中ObservableCollection第一个元素的数据？

Question

I'm making a floating button with a CollectionView and adding the data in an ObservableCollection. In the first index of the ObservableCollection, I have links. My idea is get the links of the first index, and depends of the button you touch, go to the link they have in the list.

ViewModel.cs:

 public class ViewModel :INotifyPropertyChanged
{

   

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged(string propertyName = "")
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }



    public ObservableCollection<Items> ItemList { get; set; }

    string imageprimarybutton;
    public string ImagePrimaryButton{ get => imageprimarybutton; set {
            imageprimarybutton = value;
            OnPropertyChanged();
        } }
    public string ColorPrimaryButton { get; set; }

    public Command OpenFloating { get; }

    public Command LaunchWeb { get; }

    private bool isVisible;

    public bool IsVisible
    {
        get => isVisible;
        set
        {
            isVisible = value;
            OnPropertyChanged();
        }
    }


    public ViewModel() {

        OpenFloating = new Command(openFloatingButton);
        LaunchWeb = new Command(openApp);
        ItemList = new ObservableCollection<Items>();

        IsVisible = false;

        ImagePrimaryButton = "dots.png";

        ColorPrimaryButton = "#B52D50";

       // All images must be the same resolution(256x256 recommended, trim the image is recommended)         
        ItemList.Add(new Items { Website="https://facebook.com",Image="facebook.png",ColorButton= "#B52D50" });
        ItemList.Add(new Items { Website = "https://google.com", Image = "twitter.png", ColorButton = "#B52D50" });
        ItemList.Add(new Items { Website = "https://twitter.com", Image = "insta.png", ColorButton = "#B52D50" });
        ItemList.Add(new Items { Website = "https://instagram.com", Image = "linkedin.png", ColorButton = "#B52D50" });
       


    }

    Boolean firstStart = true;
    Boolean nextClick = true;

    public void openFloatingButton()
    {


        if (firstStart)
        {
            ImagePrimaryButton = "cross.png";
            IsVisible = true;
            firstStart = false;

        }
        else
        {


            if (nextClick)
            {
                ImagePrimaryButton = "dots.png";
                IsVisible = false;
                nextClick = false;

            }
            else
            {
                ImagePrimaryButton = "cross.png";
                IsVisible = true;
                nextClick = true;

            }



        }
    }

    public void openApp()
    {
     //Method to get the link and go to the url

    }


}

MainPage.xaml:

MainPage.xaml

Answer 1

depends of the button you touch, go to the link they have in the list.

If you want to open the url that define in the property Website when user click the ImageButton, you could pass the Website as CommandParameter

in xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" xmlns:converters="clr-namespace:xxx"
             x:Class="xxx.MainPage"
             
             x:Name="page"  // set name of ContentPage
             
             >

 <ImageButton
                
       Command="{Binding Source={x:Reference page},Path=BindindContext.LaunchWeb}"
       CommandParameter="{Binding Website}"
       //...
                
    />

in ViewModel

using Xamarin.Essentials;

public ICommand LaunchWeb { get; private set; }

LaunchWeb = new Command(async(url)=> {
            
   //url here is the website of the item that you click 
   // now you can do something you want

  string AppLink = (string)url;

  await Launcher.TryOpenAsync(AppLink);
            
 });