Question

我想将我的条目和我的标签绑定到我的视图模型中的一个类，所以每当我的条目更改时，我的标签和我的类视图模型也会发生变化

这是我的代码

模型

public class MyModel
{
    public string Name { get; set; }
    public string Description { get; set; }
}

查看模型

public class MyViewModel : INotifyPropertyChanged
{
    public MyViewModel()
    {
        Model = new MyModel();
    }

    private MyModel _Model;
    public MyModel Model
    {
        get { return _Model; }
        set
        {
            _Model = Model;
            OnPropertyChanged();
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    public void OnPropertyChanged([CallerMemberName]string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

BehindCode

public partial class Page1 : ContentPage
{
    public Page1()
    {
        InitializeComponent();
        BindingContext = new MyViewModel();
    }
}

页

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="RKE.Page1">
    <StackLayout>
        <Label Text="{Binding Model.Name}"/>
        <Entry Text="{Binding Model.Name}"/>
    </StackLayout>
</ContentPage>

Answer 1

您还需要为模型实现INotify

public class MyModel:INotifyPropertyChanged
{
    string _name;
    string _description;

    public event PropertyChangedEventHandler PropertyChanged;

    public string Name 
    { 
        get => _name; 
        set
        {
            _name = value;
            OnPropertyChanged(); 
        } 
    }

    public string Description 
    { 
        get => _description;
        set
        {
            _Description = value; 
            OnPropertyChanged(); 
        }
    }

    void OnPropertyChanged([CallerMemberName]string propertyName = "") =>
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}

Xamarin表单绑定到嵌套类

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