C# ObservableCollection不注意其中的项何时更改（即使INotifyPropertyChanged）
是否有人知道此代码不起作用的原因：C# ObservableCollection不注意其中的项何时更改（即使INotifyPropertyChanged）,c#,observablecollection,inotifypropertychanged,C#,Observablecollection,Inotifypropertychanged,是否有人知道此代码不起作用的原因： public class CollectionViewModel : ViewModelBase { public ObservableCollection<EntityViewModel> ContentList { get { return _contentList; } set { _contentList = value;
public class CollectionViewModel : ViewModelBase {
public ObservableCollection<EntityViewModel> ContentList
{
get { return _contentList; }
set
{
_contentList = value;
RaisePropertyChanged("ContentList");
//I want to be notified here when something changes..?
//debugger doesn't stop here when IsRowChecked is toggled
}
}
}
public class EntityViewModel : ViewModelBase
{
private bool _isRowChecked;
public bool IsRowChecked
{
get { return _isRowChecked; }
set { _isRowChecked = value; RaisePropertyChanged("IsRowChecked"); }
}
}
公共类集合ViewModel:ViewModelBase{
公共可观察收集内容列表
{
获取{return\u contentList；}
设置
{
_contentList=value；
RaisePropertyChanged（“内容列表”）；
//我想在发生变化时在这里得到通知。。？
//当IsRowChecked被切换时，调试器不会在此停止
}
}
}
公共类EntityViewModel:ViewModelBase
{
私人住宅已检查完毕；
公共图书馆已被查封
{
获取{return\u isRowChecked；}
设置{u isRowChecked=value；RaisePropertyChanged（“isRowChecked”）；}
}
}
ViewModelBaseRaisePropertyChangedpublic class CollectionViewModel : ViewModelBase
{
public ObservableCollection<EntityViewModel> ContentList
{
get { return _contentList; }
}
public CollectionViewModel()
{
_contentList = new ObservableCollection<EntityViewModel>();
_contentList.CollectionChanged += ContentCollectionChanged;
}
public void ContentCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
//This will get called when the collection is changed
}
}
公共类集合ViewModel:ViewModelBase
{
公共可观察收集内容列表
{
获取{return\u contentList；}
}
公共集合视图模型（）
{
_contentList=新的ObservableCollection（）；
_contentList.CollectionChanged+=ContentCollectionChanged；
}
public void ContentCollectionChanged（对象发送方，NotifyCollectionChangedEventArgs e）
{
//当集合发生更改时，将调用此函数
}
}
好吧，这是我今天两次被MSDN文档错误所困扰。我给你的链接上写着： 在添加、删除项目时发生， 已更改、移动或整个列表被删除 刷新 但当一个项目被更改时，它实际上不会触发。我想你需要一种更为粗暴的方法：
public class CollectionViewModel : ViewModelBase
{
public ObservableCollection<EntityViewModel> ContentList
{
get { return _contentList; }
}
public CollectionViewModel()
{
_contentList = new ObservableCollection<EntityViewModel>();
_contentList.CollectionChanged += ContentCollectionChanged;
}
public void ContentCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e.Action == NotifyCollectionChangedAction.Remove)
{
foreach(EntityViewModel item in e.OldItems)
{
//Removed items
item.PropertyChanged -= EntityViewModelPropertyChanged;
}
}
else if (e.Action == NotifyCollectionChangedAction.Add)
{
foreach(EntityViewModel item in e.NewItems)
{
//Added items
item.PropertyChanged += EntityViewModelPropertyChanged;
}
}
}
public void EntityViewModelPropertyChanged(object sender, PropertyChangedEventArgs e)
{
//This will get called when the property of an object inside the collection changes
}
}
公共类集合ViewModel:ViewModelBase
{
公共可观察收集内容列表
{
获取{return\u contentList；}
}
公共集合视图模型（）
{
_contentList=新的ObservableCollection（）；
_contentList.CollectionChanged+=ContentCollectionChanged；
}
public void ContentCollectionChanged（对象发送方，NotifyCollectionChangedEventArgs e）
{
if（e.Action==NotifyCollectionChangedAction.Remove）
{
foreach（e.OldItems中的EntityViewModel项）
{
//删除的项目
item.PropertyChanged-=EntityViewModelPropertyChanged；
}
}
else if（e.Action==NotifyCollectionChangedAction.Add）
{
foreach（e.NewItems中的EntityViewModel项）
{
//新增项目
item.PropertyChanged+=EntityViewModelPropertyChanged；
}
}
}
public void EntityViewModelPropertyChanged（对象发送方，PropertyChangedEventArgs e）
{
//当集合内对象的属性更改时，将调用此函数
}
}
如果您非常需要它，您可能希望将自己的
ObservableCollection属性更改CollectionChangedusing System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Collections;
namespace somethingelse
{
public class ObservableCollectionEx<T> : ObservableCollection<T> where T : INotifyPropertyChanged
{
// this collection also reacts to changes in its components' properties
public ObservableCollectionEx() : base()
{
this.CollectionChanged +=new System.Collections.Specialized.NotifyCollectionChangedEventHandler(ObservableCollectionEx_CollectionChanged);
}
void ObservableCollectionEx_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
if (e.Action == NotifyCollectionChangedAction.Remove)
{
foreach(T item in e.OldItems)
{
//Removed items
item.PropertyChanged -= EntityViewModelPropertyChanged;
}
}
else if (e.Action == NotifyCollectionChangedAction.Add)
{
foreach(T item in e.NewItems)
{
//Added items
item.PropertyChanged += EntityViewModelPropertyChanged;
}
}
}
public void EntityViewModelPropertyChanged(object sender, PropertyChangedEventArgs e)
{
//This will get called when the property of an object inside the collection changes - note you must make it a 'reset' - I don't know, why
NotifyCollectionChangedEventArgs args = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset);
OnCollectionChanged(args);
}
}
}
public TrulyObservableCollection()
: base()
{
HookupCollectionChangedEvent();
}
public TrulyObservableCollection(IEnumerable<T> collection)
: base(collection)
{
foreach (T item in collection)
item.PropertyChanged += ItemPropertyChanged;
HookupCollectionChangedEvent();
}
public TrulyObservableCollection(List<T> list)
: base(list)
{
list.ForEach(item => item.PropertyChanged += ItemPropertyChanged);
HookupCollectionChangedEvent();
}
private void HookupCollectionChangedEvent()
{
CollectionChanged += new NotifyCollectionChangedEventHandler(TrulyObservableCollectionChanged);
}
使用系统；
使用System.Collections.Generic；
使用System.Linq；
使用系统文本；
使用系统组件模型；
使用System.Collections.ObjectModel；
使用System.Collections.Specialized；
使用系统集合；
名称空间somethingelse
{
公共类ObservableCollectionEx:ObservableCollection，其中T:INotifyPropertyChanged
{
//此集合还对其组件属性的更改作出反应
public observeCollectionEx（）：base（）
{
this.CollectionChanged+=新系统.Collections.Specialized.NotifyCollectionChangedEventHandler（ObservableCollectionEx\u CollectionChanged）；
}
void observeCollectionEx_CollectionChanged（对象发送方，System.Collections.Specialized.NotifyCollectionChangedEventArgs e）
{
if（e.Action==NotifyCollectionChangedAction.Remove）
{
foreach（e.OldItems中的T项）
{
//删除的项目
item.PropertyChanged-=EntityViewModelPropertyChanged；
}
}
else if（e.Action==NotifyCollectionChangedAction.Add）
{
foreach（e.NewItems中的T项）
{
//新增项目
item.PropertyChanged+=EntityViewModelPropertyChanged；
}
}
}
public void EntityViewModelPropertyChanged（对象发送方，PropertyChangedEventArgs e）
{
//当集合内对象的属性发生更改时，将调用此函数-请注意，必须对其进行“重置”-我不知道，为什么
NotifyCollectionChangedEventArgs args=新的NotifyCollectionChangedEventArgs（NotifyCollectionChangedAction.Reset）；
OnCollectionChanged（args）；
}
}
}
if (e.Action == NotifyCollectionChangedAction.Remove)
{
foreach(T item in e.NewItems)
{
//Removed items
item.PropertyChanged -= EntityViewModelPropertyChanged;
}
}
if (e.Action == NotifyCollectionChangedAction.Remove)
{
foreach(T item in e.OldItems)
{
//Removed items
item.PropertyChanged -= EntityViewModelPropertyChanged;
}
}
如果操作为.Remove，“e.NewItems”似乎会生成null。这里有一个drop-in类，它将ObservableCollection子类化，并在列表项上的属性更改时实际引发重置操作。它强制执行所有项以实现
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel; // ObservableCollection
using System.ComponentModel; // INotifyPropertyChanged
using System.Collections.Specialized; // NotifyCollectionChangedEventHandler
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ObservableCollectionTest
{
class Program
{
static void Main(string[] args)
{
// ATTN: Please note it's a "TrulyObservableCollection" that's instantiated. Otherwise, "Trades[0].Qty = 999" will NOT trigger event handler "Trades_CollectionChanged" in main.
// REF: http://stackoverflow.com/questions/8490533/notify-observablecollection-when-item-changes
TrulyObservableCollection<Trade> Trades = new TrulyObservableCollection<Trade>();
Trades.Add(new Trade { Symbol = "APPL", Qty = 123 });
Trades.Add(new Trade { Symbol = "IBM", Qty = 456});
Trades.Add(new Trade { Symbol = "CSCO", Qty = 789 });
Trades.CollectionChanged += Trades_CollectionChanged;
Trades.ItemPropertyChanged += PropertyChangedHandler;
Trades.RemoveAt(2);
Trades[0].Qty = 999;
Console.WriteLine("Hit any key to exit");
Console.ReadLine();
return;
}
static void PropertyChangedHandler(object sender, PropertyChangedEventArgs e)
{
Console.WriteLine(DateTime.Now.ToString() + ", Property changed: " + e.PropertyName + ", Symbol: " + ((Trade) sender).Symbol + ", Qty: " + ((Trade) sender).Qty);
return;
}
static void Trades_CollectionChanged(object sender, EventArgs e)
{
Console.WriteLine(DateTime.Now.ToString() + ", Collection changed");
return;
}
}
#region TrulyObservableCollection
public class TrulyObservableCollection<T> : ObservableCollection<T>
where T : INotifyPropertyChanged
{
public event PropertyChangedEventHandler ItemPropertyChanged;
public TrulyObservableCollection()
: base()
{
CollectionChanged += new NotifyCollectionChangedEventHandler(TrulyObservableCollection_CollectionChanged);
}
void TrulyObservableCollection_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e.NewItems != null)
{
foreach (Object item in e.NewItems)
{
(item as INotifyPropertyChanged).PropertyChanged += new PropertyChangedEventHandler(item_PropertyChanged);
}
}
if (e.OldItems != null)
{
foreach (Object item in e.OldItems)
{
(item as INotifyPropertyChanged).PropertyChanged -= new PropertyChangedEventHandler(item_PropertyChanged);
}
}
}
void item_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
NotifyCollectionChangedEventArgs a = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset);
OnCollectionChanged(a);
if (ItemPropertyChanged != null)
{
ItemPropertyChanged(sender, e);
}
}
}
#endregion
#region Sample entity
class Trade : INotifyPropertyChanged
{
protected string _Symbol;
protected int _Qty = 0;
protected DateTime _OrderPlaced = DateTime.Now;
public DateTime OrderPlaced
{
get { return _OrderPlaced; }
}
public string Symbol
{
get
{
return _Symbol;
}
set
{
_Symbol = value;
NotifyPropertyChanged("Symbol");
}
}
public int Qty
{
get
{
return _Qty;
}
set
{
_Qty = value;
NotifyPropertyChanged("Qty");
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged(String propertyName = "")
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
#endregion
}
public TrulyObservableCollection()
: base()
{
HookupCollectionChangedEvent();
}
public TrulyObservableCollection(IEnumerable<T> collection)
: base(collection)
{
foreach (T item in collection)
item.PropertyChanged += ItemPropertyChanged;
HookupCollectionChangedEvent();
}
public TrulyObservableCollection(List<T> list)
: base(list)
{
list.ForEach(item => item.PropertyChanged += ItemPropertyChanged);
HookupCollectionChangedEvent();
}
private void HookupCollectionChangedEvent()
{
CollectionChanged += new NotifyCollectionChangedEventHandler(TrulyObservableCollectionChanged);
}
ObservableCollection<EntityViewModel> tmpList= new ObservableCollection<EntityViewModel>();
tmpList.Add(new EntityViewModel(){IsRowChecked=false}); //Example
tmpList[0].IsRowChecked= true; //Example
...
ContentList=tmpList;
public static TrulyObservableCollection<T> ToTrulyObservableCollection<T>(this List<T> list)
where T : INotifyPropertyChanged
{
var newList = new TrulyObservableCollection<T>();
if (list != null)
{
list.ForEach(o => newList.Add(o));
}
return newList;
}
public void EntityViewModelPropertyChanged(object sender, PropertyChangedEventArgs e)
{
NotifyCollectionChangedEventArgs args = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset);
OnCollectionChanged(args);
}
void item_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
var index = this.IndexOf((T)sender);
this.RemoveAt(index);
this.Insert(index, (T)sender);
var a = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, sender);
OnCollectionChanged(a);
}
public class SpecialObservableCollection<T> : ObservableCollection<T>
{
public SpecialObservableCollection()
{
this.CollectionChanged += OnCollectionChanged;
}
void OnCollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
AddOrRemoveListToPropertyChanged(e.NewItems,true);
AddOrRemoveListToPropertyChanged(e.OldItems,false);
}
private void AddOrRemoveListToPropertyChanged(IList list, Boolean add)
{
if (list == null) { return; }
foreach (object item in list)
{
INotifyPropertyChanged o = item as INotifyPropertyChanged;
if (o != null)
{
if (add) { o.PropertyChanged += ListItemPropertyChanged; }
if (!add) { o.PropertyChanged -= ListItemPropertyChanged; }
}
else
{
throw new Exception("INotifyPropertyChanged is required");
}
}
}
void ListItemPropertyChanged(object sender, PropertyChangedEventArgs e)
{
OnListItemChanged(this, e);
}
public delegate void ListItemChangedEventHandler(object sender, PropertyChangedEventArgs e);
public event ListItemChangedEventHandler ListItemChanged;
private void OnListItemChanged(Object sender, PropertyChangedEventArgs e)
{
if (ListItemChanged != null) { this.ListItemChanged(this, e); }
}
}
using NUnit.Framework;
using Utilities;
using Microsoft.Practices.Prism.Mvvm;
using System.Collections.Specialized;
using System.Collections.Generic;
namespace Test_Utilities
{
[TestFixture]
public class Test_FullyObservableCollection : AssertionHelper
{
public class NotifyingTestClass : BindableBase
{
public int Id
{
get { return _Id; }
set { SetProperty(ref _Id, value); }
}
private int _Id;
public string Name
{
get { return _Name; }
set { SetProperty(ref _Name, value); }
}
private string _Name;
}
FullyObservableCollection<NotifyingTestClass> TestCollection;
NotifyingTestClass Fred;
NotifyingTestClass Betty;
List<NotifyCollectionChangedEventArgs> CollectionEventList;
List<ItemPropertyChangedEventArgs> ItemEventList;
[SetUp]
public void Init()
{
Fred = new NotifyingTestClass() { Id = 1, Name = "Fred" };
Betty = new NotifyingTestClass() { Id = 4, Name = "Betty" };
TestCollection = new FullyObservableCollection<NotifyingTestClass>()
{
Fred,
new NotifyingTestClass() {Id = 2, Name = "Barney" },
new NotifyingTestClass() {Id = 3, Name = "Wilma" }
};
CollectionEventList = new List<NotifyCollectionChangedEventArgs>();
ItemEventList = new List<ItemPropertyChangedEventArgs>();
TestCollection.CollectionChanged += (o, e) => CollectionEventList.Add(e);
TestCollection.ItemPropertyChanged += (o, e) => ItemEventList.Add(e);
}
// Change existing member property: just ItemPropertyChanged(IPC) should fire
[Test]
public void DetectMemberPropertyChange()
{
TestCollection[0].Id = 7;
Expect(CollectionEventList.Count, Is.EqualTo(0));
Expect(ItemEventList.Count, Is.EqualTo(1), "IPC count");
Expect(ItemEventList[0].PropertyName, Is.EqualTo(nameof(Fred.Id)), "Field Name");
Expect(ItemEventList[0].CollectionIndex, Is.EqualTo(0), "Collection Index");
}
// Add new member, change property: CollectionPropertyChanged (CPC) and IPC should fire
[Test]
public void DetectNewMemberPropertyChange()
{
TestCollection.Add(Betty);
Expect(TestCollection.Count, Is.EqualTo(4));
Expect(TestCollection[3].Name, Is.EqualTo("Betty"));
Expect(ItemEventList.Count, Is.EqualTo(0), "Item Event count");
Expect(CollectionEventList.Count, Is.EqualTo(1), "Collection Event count");
Expect(CollectionEventList[0].Action, Is.EqualTo(NotifyCollectionChangedAction.Add), "Action (add)");
Expect(CollectionEventList[0].OldItems, Is.Null, "OldItems count");
Expect(CollectionEventList[0].NewItems.Count, Is.EqualTo(1), "NewItems count");
Expect(CollectionEventList[0].NewItems[0], Is.EqualTo(Betty), "NewItems[0] dereference");
CollectionEventList.Clear(); // Empty for next operation
ItemEventList.Clear();
TestCollection[3].Id = 7;
Expect(CollectionEventList.Count, Is.EqualTo(0), "Collection Event count");
Expect(ItemEventList.Count, Is.EqualTo(1), "Item Event count");
Expect(TestCollection[ItemEventList[0].CollectionIndex], Is.EqualTo(Betty), "Collection Index dereference");
}
// Remove member, change property: CPC should fire for removel, neither CPC nor IPC should fire for change
[Test]
public void CeaseListentingWhenMemberRemoved()
{
TestCollection.Remove(Fred);
Expect(TestCollection.Count, Is.EqualTo(2));
Expect(TestCollection.IndexOf(Fred), Is.Negative);
Expect(ItemEventList.Count, Is.EqualTo(0), "Item Event count (pre change)");
Expect(CollectionEventList.Count, Is.EqualTo(1), "Collection Event count (pre change)");
Expect(CollectionEventList[0].Action, Is.EqualTo(NotifyCollectionChangedAction.Remove), "Action (remove)");
Expect(CollectionEventList[0].OldItems.Count, Is.EqualTo(1), "OldItems count");
Expect(CollectionEventList[0].NewItems, Is.Null, "NewItems count");
Expect(CollectionEventList[0].OldItems[0], Is.EqualTo(Fred), "OldItems[0] dereference");
CollectionEventList.Clear(); // Empty for next operation
ItemEventList.Clear();
Fred.Id = 7;
Expect(CollectionEventList.Count, Is.EqualTo(0), "Collection Event count (post change)");
Expect(ItemEventList.Count, Is.EqualTo(0), "Item Event count (post change)");
}
// Move member in list, change property: CPC should fire for move, IPC should fire for change
[Test]
public void MoveMember()
{
TestCollection.Move(0, 1);
Expect(TestCollection.Count, Is.EqualTo(3));
Expect(TestCollection.IndexOf(Fred), Is.GreaterThan(0));
Expect(ItemEventList.Count, Is.EqualTo(0), "Item Event count (pre change)");
Expect(CollectionEventList.Count, Is.EqualTo(1), "Collection Event count (pre change)");
Expect(CollectionEventList[0].Action, Is.EqualTo(NotifyCollectionChangedAction.Move), "Action (move)");
Expect(CollectionEventList[0].OldItems.Count, Is.EqualTo(1), "OldItems count");
Expect(CollectionEventList[0].NewItems.Count, Is.EqualTo(1), "NewItems count");
Expect(CollectionEventList[0].OldItems[0], Is.EqualTo(Fred), "OldItems[0] dereference");
Expect(CollectionEventList[0].NewItems[0], Is.EqualTo(Fred), "NewItems[0] dereference");
CollectionEventList.Clear(); // Empty for next operation
ItemEventList.Clear();
Fred.Id = 7;
Expect(CollectionEventList.Count, Is.EqualTo(0), "Collection Event count (post change)");
Expect(ItemEventList.Count, Is.EqualTo(1), "Item Event count (post change)");
Expect(TestCollection[ItemEventList[0].CollectionIndex], Is.EqualTo(Fred), "Collection Index dereference");
}
// Clear list, chnage property: only CPC should fire for clear and neither for property change
[Test]
public void ClearList()
{
TestCollection.Clear();
Expect(TestCollection.Count, Is.EqualTo(0));
Expect(ItemEventList.Count, Is.EqualTo(0), "Item Event count (pre change)");
Expect(CollectionEventList.Count, Is.EqualTo(1), "Collection Event count (pre change)");
Expect(CollectionEventList[0].Action, Is.EqualTo(NotifyCollectionChangedAction.Reset), "Action (reset)");
Expect(CollectionEventList[0].OldItems, Is.Null, "OldItems count");
Expect(CollectionEventList[0].NewItems, Is.Null, "NewItems count");
CollectionEventList.Clear(); // Empty for next operation
ItemEventList.Clear();
Fred.Id = 7;
Expect(CollectionEventList.Count, Is.EqualTo(0), "Collection Event count (post change)");
Expect(ItemEventList.Count, Is.EqualTo(0), "Item Event count (post change)");
}
}
}
private BindingList<TfsFile> _tfsFiles;
public BindingList<TfsFile> TfsFiles
{
get { return _tfsFiles; }
set
{
_tfsFiles = value;
NotifyPropertyChanged();
}
}
foreach (var file in TfsFiles)
{
SelectedFile = file;
file.Name = "Different Text";
TfsFiles.ResetBindings();
}
namespace Models
{
public class TfsFile
{
public string ImagePath { get; set; }
public string FullPath { get; set; }
public string Name { get; set; }
public string Text { get; set; }
}
}
public class Model:INotifyPropertyChange
{
//...
}
public ObservableCollection<Model> {get; set;}
<Window.DataContext>
<local:ViewModel/>
</Window.DataContext>
<Grid>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<ListView
Margin="10"
BorderBrush="Black"
HorizontalAlignment="Center"
SelectedItem="{Binding SelectedPerson}"
ItemsSource="{Binding Persons}">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Label Content="{Binding Name}"/>
<Label Content="-"/>
<Label Content="{Binding Age}"/>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<Grid
Grid.Row="1"
VerticalAlignment="Center"
HorizontalAlignment="Center">
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<Label
VerticalAlignment="Center"
Content="Name:"/>
<TextBox
Text="{Binding SelectedPerson.Name,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
Margin="10"
Grid.Column="1"
Width="100"/>
<Label
VerticalAlignment="Center"
Grid.Row="1"
Content="Age:"/>
<TextBox
Text="{Binding SelectedPerson.Age,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
Margin="10"
Grid.Row="1"
Grid.Column="1"
Width="100"/>
</Grid>
</Grid>
public class PersonModel:INotifyPropertyChanged
{
public string Name
{
get => _name;
set
{
_name = value;
OnPropertyChanged();
}
}
public int Age
{
get => _age;
set
{
_age = value;
OnPropertyChanged();
}
}
private string _name;
private int _age;
//INotifyPropertyChanged implementation
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
public class ViewModel:INotifyPropertyChanged
{
public ViewModel()
{
Persons = new ObservableCollection<PersonModel>
{
new PersonModel
{
Name = "Jack",
Age = 30
},
new PersonModel
{
Name = "Jon",
Age = 23
},
new PersonModel
{
Name = "Max",
Age = 23
},
};
}
public ObservableCollection<PersonModel> Persons { get;}
public PersonModel SelectedPerson
{
get => _selectedPerson;
set
{
_selectedPerson = value;
OnPropertyChanged();
}
}
//INotifyPropertyChanged Implementation
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
private PersonModel _selectedPerson;
}
speakers.list[0].Status = "offline";
speakers.list[0] = new Speaker(speakers.list[0]);
speakers.list[0].Status = "offline";
//speakers.list[0] = new Speaker(speakers.list[0]);
var tmp = JsonConvert.SerializeObject(speakers.list[0]);
var tmp2 = JsonConvert.DeserializeObject<Speaker>(tmp);
speakers.list[0] = tmp2;
public static class ObservableCollectionEx
{
public static void SetOnCollectionItemPropertyChanged<T>(this T _this, PropertyChangedEventHandler handler)
where T : INotifyCollectionChanged, ICollection<INotifyPropertyChanged>
{
_this.CollectionChanged += (sender,e)=> {
if (e.NewItems != null)
{
foreach (Object item in e.NewItems)
{
((INotifyPropertyChanged)item).PropertyChanged += handler;
}
}
if (e.OldItems != null)
{
foreach (Object item in e.OldItems)
{
((INotifyPropertyChanged)item).PropertyChanged -= handler;
}
}
};
}
}
public class Test
{
public static void MyExtensionTest()
{
ObservableCollection<INotifyPropertyChanged> c = new ObservableCollection<INotifyPropertyChanged>();
c.SetOnCollectionItemPropertyChanged((item, e) =>
{
//whatever you want to do on item change
});
}
}
int index = NotificationDetails.IndexOf(notificationDetails);
NotificationDetails.Remove(notificationDetails);
NotificationDetails.Insert(index, notificationDetails);