如何获取视图组件"handle"

Question

我有开关。当我点击那个开关时，我捕捉到false真正或价值。但是当我捕捉到true我想禁用或对我的部门条目做类似的事情，但我没有"处理"。到那个分量。如何在MVVM模式中做到这一点，如何获得一个"处理";到那个组件?因为在代码后面这很简单。对不起，我的英语不好。

internal class RegisterPageViewModel : INotifyPropertyChanged
{
private string _name;
private string _switchValue;
public string Name
{
get => _name;
set
{
_name = value;
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Name)));
}
}
public string SwitchValue
{
get => _switchValue;
set => _switchValue = value;
}
public string MiddleName { get; set; }
public string Surname { get; set; }
public string Email { get; set; }
public string PhoneNumber { get; set; }
public string DepartmentCode { get; set; }
public ICommand ImAnEmployeeCommand { get; }
public RegisterPageViewModel()
{
ImAnEmployeeCommand = new Command<bool>(AmAnEmployeeExecute);
}
private void AmAnEmployeeExecute(bool switchValue)
{
if (switchValue)
{
App.Current.MainPage.DisplayAlert("sds", switchValue.ToString(), "dsad");
}
}
public event PropertyChangedEventHandler PropertyChanged;
}

Answer 1

您可以使用数据绑定来实现这一点。

我创建了一个简单的演示并实现了这个功能。

你可以参考下面的代码:

1。为RegisterPageViewModel添加字段IsChenked和实现接口INotifyPropertyChanged:

public  class RegisterPageViewModel: INotifyPropertyChanged
{
//add new field here
bool _isChenked;
public bool IsChenked
{
get
{
return _isChenked;
}
set
{
_isChenked = value;
// Do any other stuff you want here
OnPropertyChanged(nameof(IsChenked));
AmAnEmployeeExecute(IsChenked);
}
}
//other code
public string MiddleName { get; set; }
public string Surname { get; set; }
public string Email { get; set; }
public string PhoneNumber { get; set; }
public string DepartmentCode { get; set; }
public ICommand ImAnEmployeeCommand { get; }
public RegisterPageViewModel()
{
ImAnEmployeeCommand = new Command<bool>(AmAnEmployeeExecute);
IsChenked = true;
}
private void AmAnEmployeeExecute(bool switchValue)
{
if (switchValue)
{
System.Diagnostics.Debug.WriteLine("switchValue is  true");
}
else {
System.Diagnostics.Debug.WriteLine("switchValue is  false");
}
}
protected virtual void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
}

2。并在YourPage.xaml中绑定IsChenked域

<ContentPage.BindingContext>
<formapp619:RegisterPageViewModel></formapp619:RegisterPageViewModel>
</ContentPage.BindingContext>
<StackLayout>
<Entry  Placeholder="test" IsVisible="{Binding IsChenked}"/>
<Switch  IsToggled="{Binding IsChenked}"/>
</StackLayout>