CODEWITHSUNDEEP
xamarin.formsdata-binding
Behzad Changizi
Behzad Changizi

Reputation: 33

Bindig problems! Bind one page to multiple pages

guys Lets say you have page1.xaml and page1.cs and there is a class (school) in this page1.cs that you want to use in page2.xaml as binding object. I can do this in xaml page of page2,

1.But how can I do it in page2.cs?

2.I don't want to use BindingContext = page1; because I want to bind multiple pages to this page2.

Can I use multy binding in xaml page or what should I do?

this is my Model:

public class EnergyX
    {
        [PrimaryKey, AutoIncrement]

        public int Id { get; set; }
        public string Score { get; set; }

    }

and In my page1.cs I used SQL to save User input:

private ObservableCollection<EnergyX> _energyX;
        public ObservableCollection<EnergyX> energyX
        {
            get { return _energyX; }
            set
            {
                _energyX = value;
                OnPropertyChanged("energyX");
            }
        }

save this energyx with SQL:

energyX = new ObservableCollection<EnergyX>(conn.Table<EnergyX>().ToList());

In my page2.xaml:

<listview {binding energyx}/>
<lable {binding Score}/>

Upvotes: 0

Views: 167

Answers (1)

Leo Zhu
Leo Zhu

Reputation: 14956

You could define your viewmodel as a singleton,then you could bind it in multiple pages.

Like:

public  class YourViewModel
{

    public static YourViewModel viewModel;
    public ObservableCollection<EnergyX> energyX { get; set; } = new ObservableCollection<EnergyX>();

    public static YourViewModel instance()
    {
        if (viewModel == null)
        {
            viewModel = new YourViewModel();
        }
        return viewModel;
    }

    public void Save(List<EnergyX> list)
    {

        foreach (var item in list)
        {
            energyX.Add(item);
        }
    }
}

then in your page1.xaml.cs:

    public Page1()
    {
        InitializeComponent();
        BindingContext = YourViewModel.instance();
    }

    //when you want to save the energyx 
    List<EnergyX> energyx  = xxxx;
    YourViewModel.instance().Save(energyx);

then in your page2.xaml.cs:

    public Page2()
    {
        InitializeComponent();
        BindingContext = YourViewModel.instance();
    }

binding in page2.xaml:

    <listview {binding energyx}/>
    <lable {binding Score}/>

Update:

public partial class Page2 : ContentPage
{
    public ViewModel1 viewModel1 { get; set; }
    public ViewModel2 viewModel2 { get; set; }
    public Page2()
    {
        InitializeComponent();
        viewModel1 = new ViewModel1();
        viewModel2 = new ViewModel2();
        BindingContext = this;
    }
 }

then you could bind the two viewmodel in your xaml:

 <Label Text="{Binding viewModel1.Name}"></Label>
 <Label Text="{Binding viewModel2.Id}"></Label>

Upvotes: 1

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