inotifypropertychanged | 易学教程

Automatically INotifyPropertyChanged

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Is there any way to automatically get notified of property changes in a class without having to write OnPropertyChanged in every setter? (I have hundreds of properties that I want to know if they have changed). Anton suggests dynamic proxies . I've actually used the "Castle" library for something similar in the past, and while it does reduce the amount of code I've had to write, it added around 30 seconds to my program startup time (ymmv) - because it's a runtime solution. I'm wondering if there is a compile time solution, maybe using compile-time attributes... Slashene and TcKs give

INotifyPropertyChanged WPF

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问题 What is the purpose of INotifyPropertyChanged. I know this event is fired whenever a property is changed but how can the View/UI knows that this event is fired: Here is my Customer class that implements the INotifyPropertyChanged event: public class Customer : INotifyPropertyChanged { private string _firstName; public string LastName { get; set; } public event PropertyChangedEventHandler PropertyChanged; protected void OnPropertyChanged(string propertyName) { if(PropertyChanged != null)

Is [CallerMemberName] slow compared to alternatives when implementing INotifyPropertyChanged?

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问题 There are good articles that suggest different ways for implementing INotifyPropertyChanged. Consider the following basic implementation: class BasicClass : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; private void FirePropertyChanged(string propertyName) { var handler = PropertyChanged; if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName)); } private int sampleIntField; public int SampleIntProperty { get { return sampleIntField;

WPF MVVM INotifyPropertyChanged Implementation - Model or ViewModel

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问题 I have read a number of debates on where to implement INotifyPropertyChanged here on StackOverflow and other blogs but it seems that there are cases where you have to implement it on the Model. Here is my scenario - I am looking for feedback on my conclusion or is my approach wrong. I am using this implementation of an ObservableDictionary (ObservableDictionary) because I need performant queries using the key. In this dictionary I place the collection of Model objects. In my VM, I declare an

How to get property change notifications with EF 4.x DbContext generator

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问题 I\'m playing around with Entity Framework 4.3, and so I am using the DbContext Generator to create the context and entity classes. With the default EF 4 code generator template, entity classes implement INotifyPropertyChanged, and also add Changing and Changed partial methods in property setters. When I use the EF 4.x DbContext generator, as pictured below, the entity classes are much lighter, and do not include any means of tracking property changes. Here is an example: //-------------------

Automatically INotifyPropertyChanged

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问题 Is there any way to automatically get notified of property changes in a class without having to write OnPropertyChanged in every setter? (I have hundreds of properties that I want to know if they have changed). Anton suggests dynamic proxies. I\'ve actually used the \"Castle\" library for something similar in the past, and while it does reduce the amount of code I\'ve had to write, it added around 30 seconds to my program startup time (ymmv) - because it\'s a runtime solution. I\'m wondering

Notify ObservableCollection when Item changes

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问题 I found on this link ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged) some techniques to notify a Observablecollection that an item has changed. the TrulyObservableCollection in this link seems to be what i\'m looking for. public class TrulyObservableCollection<T> : ObservableCollection<T> where T : INotifyPropertyChanged { public TrulyObservableCollection() : base() { CollectionChanged += new NotifyCollectionChangedEventHandler

Implementing INotifyPropertyChanged - does a better way exist?

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问题 Microsoft should have implemented something snappy for INotifyPropertyChanged , like in the automatic properties, just specify {get; set; notify;} I think it makes a lot of sense to do it. Or are there any complications to do it? Can we ourselves implement something like \'notify\' in our properties. Is there a graceful solution for implementing INotifyPropertyChanged in your class or the only way to do it is by raising the PropertyChanged event in each property. If not can we write something

In MVVM should the ViewModel or Model implement INotifyPropertyChanged?

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问题 Most MVVM examples I have worked through have had the Model implement INotifyPropertyChanged, but in Josh Smith\'s CommandSink example the ViewModel implements INotifyPropertyChanged . I\'m still cognitively putting together the MVVM concepts, so I don\'t know if: you have to put the INotifyPropertyChanged in the ViewModel to get CommandSink to work this is just an aberration of the norm and it doesn\'t really matter you should always have the Model implement INotifyPropertyChanged and this

ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)

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问题 Does anyone know why this code doesn\'t work: 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