WPF Adding an item to a BindingList not update another Property in Viewmodel
I have this code in my viewmodel (Singleton):
/// <summary>
/// Gets or sets the person list.
/// </summary>
/// <value>
/// The person list.
/// </value>
public BindingList<Person> PersonList
{
get { return personList; }
set
{
personList = value;
OnPropertyChanged(nameof(PersonList));
OnPropertyChanged(nameof(PersonCount));
}
}
/// <summary>
/// Gets the person count.
/// </summary>
/// <value>
/// The person count.
/// </value>
public int PersonCount
{
get
{
return personList.Count();
}
}
When I add a Person to the BindingList it appears in the view correctly. A Change of one of the items of BindingList is shown correctly.
But the PersonCount is not updated and appears as "0".
The class Person is implemented like this:
public class Person : NotificationObject
{
#region Fields
private string name;
private DateTime birthDate;
private string lastName;
#endregion // Fields
#region Construction
#endregion // Construction
#region Attributes
public string Name
{
get { return name; }
set
{
name = value;
OnPropertyChanged(nameof(Name));
}
}
public string LastName
{
get { return lastName; }
set
{
lastName = value;
OnPropertyChanged(nameof(LastName));
}
}
public DateTime BirthDate
{
get { return birthDate; }
set
{
birthDate = value;
OnPropertyChanged(nameof(BirthDate));
OnPropertyChanged(nameof(Age));
}
}
public int Age
{
get { return (DateTime.Now - birthDate).Days/365; }
}
#endregion // Attributes
#region Operations
#endregion // Operations
#region Implementation
#endregion // Implementation
} // class Person
Why the PersonCount is not updated and how to do it right?
What I am doing wrong?
Thanks in advance,
Andreas
c# wpf mvvm bindinglist
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
add a comment |
I have this code in my viewmodel (Singleton):
/// <summary>
/// Gets or sets the person list.
/// </summary>
/// <value>
/// The person list.
/// </value>
public BindingList<Person> PersonList
{
get { return personList; }
set
{
personList = value;
OnPropertyChanged(nameof(PersonList));
OnPropertyChanged(nameof(PersonCount));
}
}
/// <summary>
/// Gets the person count.
/// </summary>
/// <value>
/// The person count.
/// </value>
public int PersonCount
{
get
{
return personList.Count();
}
}
When I add a Person to the BindingList it appears in the view correctly. A Change of one of the items of BindingList is shown correctly.
But the PersonCount is not updated and appears as "0".
The class Person is implemented like this:
public class Person : NotificationObject
{
#region Fields
private string name;
private DateTime birthDate;
private string lastName;
#endregion // Fields
#region Construction
#endregion // Construction
#region Attributes
public string Name
{
get { return name; }
set
{
name = value;
OnPropertyChanged(nameof(Name));
}
}
public string LastName
{
get { return lastName; }
set
{
lastName = value;
OnPropertyChanged(nameof(LastName));
}
}
public DateTime BirthDate
{
get { return birthDate; }
set
{
birthDate = value;
OnPropertyChanged(nameof(BirthDate));
OnPropertyChanged(nameof(Age));
}
}
public int Age
{
get { return (DateTime.Now - birthDate).Days/365; }
}
#endregion // Attributes
#region Operations
#endregion // Operations
#region Implementation
#endregion // Implementation
} // class Person
Why the PersonCount is not updated and how to do it right?
What I am doing wrong?
Thanks in advance,
Andreas
c# wpf mvvm bindinglist
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
add a comment |
I have this code in my viewmodel (Singleton):
/// <summary>
/// Gets or sets the person list.
/// </summary>
/// <value>
/// The person list.
/// </value>
public BindingList<Person> PersonList
{
get { return personList; }
set
{
personList = value;
OnPropertyChanged(nameof(PersonList));
OnPropertyChanged(nameof(PersonCount));
}
}
/// <summary>
/// Gets the person count.
/// </summary>
/// <value>
/// The person count.
/// </value>
public int PersonCount
{
get
{
return personList.Count();
}
}
When I add a Person to the BindingList it appears in the view correctly. A Change of one of the items of BindingList is shown correctly.
But the PersonCount is not updated and appears as "0".
The class Person is implemented like this:
public class Person : NotificationObject
{
#region Fields
private string name;
private DateTime birthDate;
private string lastName;
#endregion // Fields
#region Construction
#endregion // Construction
#region Attributes
public string Name
{
get { return name; }
set
{
name = value;
OnPropertyChanged(nameof(Name));
}
}
public string LastName
{
get { return lastName; }
set
{
lastName = value;
OnPropertyChanged(nameof(LastName));
}
}
public DateTime BirthDate
{
get { return birthDate; }
set
{
birthDate = value;
OnPropertyChanged(nameof(BirthDate));
OnPropertyChanged(nameof(Age));
}
}
public int Age
{
get { return (DateTime.Now - birthDate).Days/365; }
}
#endregion // Attributes
#region Operations
#endregion // Operations
#region Implementation
#endregion // Implementation
} // class Person
Why the PersonCount is not updated and how to do it right?
What I am doing wrong?
Thanks in advance,
Andreas
c# wpf mvvm bindinglist
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
I have this code in my viewmodel (Singleton):
/// <summary>
/// Gets or sets the person list.
/// </summary>
/// <value>
/// The person list.
/// </value>
public BindingList<Person> PersonList
{
get { return personList; }
set
{
personList = value;
OnPropertyChanged(nameof(PersonList));
OnPropertyChanged(nameof(PersonCount));
}
}
/// <summary>
/// Gets the person count.
/// </summary>
/// <value>
/// The person count.
/// </value>
public int PersonCount
{
get
{
return personList.Count();
}
}
When I add a Person to the BindingList it appears in the view correctly. A Change of one of the items of BindingList is shown correctly.
But the PersonCount is not updated and appears as "0".
The class Person is implemented like this:
public class Person : NotificationObject
{
#region Fields
private string name;
private DateTime birthDate;
private string lastName;
#endregion // Fields
#region Construction
#endregion // Construction
#region Attributes
public string Name
{
get { return name; }
set
{
name = value;
OnPropertyChanged(nameof(Name));
}
}
public string LastName
{
get { return lastName; }
set
{
lastName = value;
OnPropertyChanged(nameof(LastName));
}
}
public DateTime BirthDate
{
get { return birthDate; }
set
{
birthDate = value;
OnPropertyChanged(nameof(BirthDate));
OnPropertyChanged(nameof(Age));
}
}
public int Age
{
get { return (DateTime.Now - birthDate).Days/365; }
}
#endregion // Attributes
#region Operations
#endregion // Operations
#region Implementation
#endregion // Implementation
} // class Person
Why the PersonCount is not updated and how to do it right?
What I am doing wrong?
Thanks in advance,
Andreas
c# wpf mvvm bindinglist
c# wpf mvvm bindinglist
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
edited Dec 4 '18 at 9:00
Rekshino
2,7861728
2,7861728
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
asked Nov 23 '18 at 10:54
Andreas SusewindAndreas Susewind
234
234
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
The problem in your code is, once you bind the 'PersonList' to the view model, the list object doesn't change unless you bind another list (what happens is just items are added or removed from the list), therefore the setter of the 'PersonList' property is not called & therefore "Notify property changed" doesn't trigger for 'PersonCount'.
However as the 'PersonList' is a BindingList, added/removed items are reflected in the UI.
Solutions
1) Register 'PersonList' to ListChanged event and call 'Notify Property Changed' in the event handler.
public BindingList<Person> PersonList
{
get { return personList; }
set
{
if (personList != null)
personList.ListChanged -= PersonList_ListChanged;
personList = value;
if (personList != null)
personList.ListChanged += PersonList_ListChanged;
OnPropertyChanged(nameof(PersonList));
}
}
public PersonsDashboardViewModel()
{
PersonList = new BindingList<Person>();
PersonList.Add(new Person("Name1", "Lname1"));
PersonList.Add(new Person("Name2", "Lname2"));
}
private void PersonList_ListChanged(object sender, ListChangedEventArgs e)
{
OnPropertyChanged(nameof(PersonCount));
}
OR
2) Call 'Notify Property Changed' for 'PersonCount' where you add person items.
public void AddPersonItem()
{
PersonList.Add(new Person("Sean", "Brendon"));
OnPropertyChanged(nameof(PersonCount));
}
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
2
Your point 1) is dangerous! If you setPersonListone more time not in the constructor ofPersonsDashboardViewModelthe UI will not be updated. You have to more attentively read my answer
– Rekshino
Nov 23 '18 at 12:07
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
add a comment |
You have to invoke OnPropertyChanged(nameof(PersonCount)); where you modify the list. If it's not possible, then you have to subscribe to CollectionChanged for PersonList in setter and invoke OnPropertyChanged(nameof(PersonCount)); in event handler.
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
1
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
The problem in your code is, once you bind the 'PersonList' to the view model, the list object doesn't change unless you bind another list (what happens is just items are added or removed from the list), therefore the setter of the 'PersonList' property is not called & therefore "Notify property changed" doesn't trigger for 'PersonCount'.
However as the 'PersonList' is a BindingList, added/removed items are reflected in the UI.
Solutions
1) Register 'PersonList' to ListChanged event and call 'Notify Property Changed' in the event handler.
public BindingList<Person> PersonList
{
get { return personList; }
set
{
if (personList != null)
personList.ListChanged -= PersonList_ListChanged;
personList = value;
if (personList != null)
personList.ListChanged += PersonList_ListChanged;
OnPropertyChanged(nameof(PersonList));
}
}
public PersonsDashboardViewModel()
{
PersonList = new BindingList<Person>();
PersonList.Add(new Person("Name1", "Lname1"));
PersonList.Add(new Person("Name2", "Lname2"));
}
private void PersonList_ListChanged(object sender, ListChangedEventArgs e)
{
OnPropertyChanged(nameof(PersonCount));
}
OR
2) Call 'Notify Property Changed' for 'PersonCount' where you add person items.
public void AddPersonItem()
{
PersonList.Add(new Person("Sean", "Brendon"));
OnPropertyChanged(nameof(PersonCount));
}
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
2
Your point 1) is dangerous! If you setPersonListone more time not in the constructor ofPersonsDashboardViewModelthe UI will not be updated. You have to more attentively read my answer
– Rekshino
Nov 23 '18 at 12:07
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
add a comment |
The problem in your code is, once you bind the 'PersonList' to the view model, the list object doesn't change unless you bind another list (what happens is just items are added or removed from the list), therefore the setter of the 'PersonList' property is not called & therefore "Notify property changed" doesn't trigger for 'PersonCount'.
However as the 'PersonList' is a BindingList, added/removed items are reflected in the UI.
Solutions
1) Register 'PersonList' to ListChanged event and call 'Notify Property Changed' in the event handler.
public BindingList<Person> PersonList
{
get { return personList; }
set
{
if (personList != null)
personList.ListChanged -= PersonList_ListChanged;
personList = value;
if (personList != null)
personList.ListChanged += PersonList_ListChanged;
OnPropertyChanged(nameof(PersonList));
}
}
public PersonsDashboardViewModel()
{
PersonList = new BindingList<Person>();
PersonList.Add(new Person("Name1", "Lname1"));
PersonList.Add(new Person("Name2", "Lname2"));
}
private void PersonList_ListChanged(object sender, ListChangedEventArgs e)
{
OnPropertyChanged(nameof(PersonCount));
}
OR
2) Call 'Notify Property Changed' for 'PersonCount' where you add person items.
public void AddPersonItem()
{
PersonList.Add(new Person("Sean", "Brendon"));
OnPropertyChanged(nameof(PersonCount));
}
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
2
Your point 1) is dangerous! If you setPersonListone more time not in the constructor ofPersonsDashboardViewModelthe UI will not be updated. You have to more attentively read my answer
– Rekshino
Nov 23 '18 at 12:07
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
add a comment |
The problem in your code is, once you bind the 'PersonList' to the view model, the list object doesn't change unless you bind another list (what happens is just items are added or removed from the list), therefore the setter of the 'PersonList' property is not called & therefore "Notify property changed" doesn't trigger for 'PersonCount'.
However as the 'PersonList' is a BindingList, added/removed items are reflected in the UI.
Solutions
1) Register 'PersonList' to ListChanged event and call 'Notify Property Changed' in the event handler.
public BindingList<Person> PersonList
{
get { return personList; }
set
{
if (personList != null)
personList.ListChanged -= PersonList_ListChanged;
personList = value;
if (personList != null)
personList.ListChanged += PersonList_ListChanged;
OnPropertyChanged(nameof(PersonList));
}
}
public PersonsDashboardViewModel()
{
PersonList = new BindingList<Person>();
PersonList.Add(new Person("Name1", "Lname1"));
PersonList.Add(new Person("Name2", "Lname2"));
}
private void PersonList_ListChanged(object sender, ListChangedEventArgs e)
{
OnPropertyChanged(nameof(PersonCount));
}
OR
2) Call 'Notify Property Changed' for 'PersonCount' where you add person items.
public void AddPersonItem()
{
PersonList.Add(new Person("Sean", "Brendon"));
OnPropertyChanged(nameof(PersonCount));
}
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
The problem in your code is, once you bind the 'PersonList' to the view model, the list object doesn't change unless you bind another list (what happens is just items are added or removed from the list), therefore the setter of the 'PersonList' property is not called & therefore "Notify property changed" doesn't trigger for 'PersonCount'.
However as the 'PersonList' is a BindingList, added/removed items are reflected in the UI.
Solutions
1) Register 'PersonList' to ListChanged event and call 'Notify Property Changed' in the event handler.
public BindingList<Person> PersonList
{
get { return personList; }
set
{
if (personList != null)
personList.ListChanged -= PersonList_ListChanged;
personList = value;
if (personList != null)
personList.ListChanged += PersonList_ListChanged;
OnPropertyChanged(nameof(PersonList));
}
}
public PersonsDashboardViewModel()
{
PersonList = new BindingList<Person>();
PersonList.Add(new Person("Name1", "Lname1"));
PersonList.Add(new Person("Name2", "Lname2"));
}
private void PersonList_ListChanged(object sender, ListChangedEventArgs e)
{
OnPropertyChanged(nameof(PersonCount));
}
OR
2) Call 'Notify Property Changed' for 'PersonCount' where you add person items.
public void AddPersonItem()
{
PersonList.Add(new Person("Sean", "Brendon"));
OnPropertyChanged(nameof(PersonCount));
}
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
edited Nov 23 '18 at 13:24
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
answered Nov 23 '18 at 11:44
PrabodaPraboda
655
655
2
Your point 1) is dangerous! If you setPersonListone more time not in the constructor ofPersonsDashboardViewModelthe UI will not be updated. You have to more attentively read my answer
– Rekshino
Nov 23 '18 at 12:07
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
add a comment |
2
Your point 1) is dangerous! If you setPersonListone more time not in the constructor ofPersonsDashboardViewModelthe UI will not be updated. You have to more attentively read my answer
– Rekshino
Nov 23 '18 at 12:07
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
2
2
Your point 1) is dangerous! If you set
PersonList one more time not in the constructor of PersonsDashboardViewModel the UI will not be updated. You have to more attentively read my answer– Rekshino
Nov 23 '18 at 12:07
Your point 1) is dangerous! If you set
PersonList one more time not in the constructor of PersonsDashboardViewModel the UI will not be updated. You have to more attentively read my answer– Rekshino
Nov 23 '18 at 12:07
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Your first solution did the work. I use a separate class with BusinessLogic to alter the viewmodel. The OnPropertyChanged method is private, too. Because of this I can`t use the OnPropertyChanged-Method of the viewmodel in this BusinessLogic.
– Andreas Susewind
Nov 23 '18 at 12:11
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Agreed with @Rekshino , you have to be careful when registering events. Registering for the 'ListChanged' event in the setter of 'PersonList' is straightforward.
– Praboda
Nov 23 '18 at 13:25
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
Now it looks out better.
– Rekshino
Nov 26 '18 at 7:34
add a comment |
You have to invoke OnPropertyChanged(nameof(PersonCount)); where you modify the list. If it's not possible, then you have to subscribe to CollectionChanged for PersonList in setter and invoke OnPropertyChanged(nameof(PersonCount)); in event handler.
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
1
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
add a comment |
You have to invoke OnPropertyChanged(nameof(PersonCount)); where you modify the list. If it's not possible, then you have to subscribe to CollectionChanged for PersonList in setter and invoke OnPropertyChanged(nameof(PersonCount)); in event handler.
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
1
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
add a comment |
You have to invoke OnPropertyChanged(nameof(PersonCount)); where you modify the list. If it's not possible, then you have to subscribe to CollectionChanged for PersonList in setter and invoke OnPropertyChanged(nameof(PersonCount)); in event handler.
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
You have to invoke OnPropertyChanged(nameof(PersonCount)); where you modify the list. If it's not possible, then you have to subscribe to CollectionChanged for PersonList in setter and invoke OnPropertyChanged(nameof(PersonCount)); in event handler.
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
answered Nov 23 '18 at 10:58
RekshinoRekshino
2,7861728
2,7861728
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
1
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
add a comment |
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
1
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
Thank you for your answer. My Personlist is instantiated in the constructor respectively in a reset-method to reset the viewmodel if needed. Is it what you mean with "in setter" ? Thanks in advance.
– Andreas Susewind
Nov 23 '18 at 14:44
1
1
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
@AndreasSusewind If you reassign the list in the reset method, then you have to unsubscribe the previous event handler and set the new one. Praboda has changed the answer, now is subscription in setter.
– Rekshino
Nov 26 '18 at 7:27
add a comment |
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