Differences between revisions 2 and 4 (spanning 2 versions)
⇤ ← Revision 2 as of 2019-03-04 22:59:40 →
Size: 1125
Editor: scot
Comment:
← Revision 4 as of 2023-09-14 23:04:09 → ⇥
Size: 1316
Editor: scot
Comment:
Deletions are marked like this. Additions are marked like this.
Line 7: Line 7:
private ObservableCollection<string> _Area = new ObservableCollection<string>();
public ObservableCollection<string> Area		 private BindingList<string> _Area = new BindingList<string>();
public BindingList<string> Area
Line 11: Line 11:
    set => SetField(ref _Area, value);     set => SetField<BindingList<string>>(ref _Area, value);
Line 25: Line 25:
I used to use something like this: Suppose that the value you are setting with SetField is a property of a Model object. You may get an error that says, "A non ref-returning property or indexer may not be used as an out or ref value." There is an easy fix for this.
Line 27: Line 27:
{{{#!highlight csharp

public int test {
    get
    {
        return _test;
    }
    set
    {
        _test = value;
        OnPropertyChanged();
    }		 {{{#!hightlight csharp
private BindingList<string> _Area = new BindingList<string>();
public BindingList<string> Area
{
    get => _Area;
    set => _Area = SetField<BindingList<string>>(value);
Line 43: Line 37:
protected void OnPropertyChanged([CallerMemberName] string propertyName = null) public event PropertyChangedEventHandler PropertyChanged;

protected void SetField<T>(T value, [CallerMemberName] string propertyName = null)
Line 45: Line 41:
    if (PropertyChange != null)
    {
     PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }		     PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    return value;
Line 51: Line 45:

And before that we just passed in the name. It was kind of a pain.

Implementing INotifyPropertyChanged

It's changed a lot over the years. Here is the latest iteration that I use.

Toggle line numbers 
   1 private BindingList<string> _Area = new BindingList<string>();
   2 public BindingList<string> Area
   3 {
   4     get => _Area;
   5     set => SetField<BindingList<string>>(ref _Area, value);
   6 }
   7 
   8 //...
   9 
  10 public event PropertyChangedEventHandler PropertyChanged;
  11 
  12 protected void SetField<T>(ref T field, T value, [CallerMemberName] string propertyName = null)
  13 {
  14     field = value;
  15     PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
  16 }

Suppose that the value you are setting with SetField is a property of a Model object. You may get an error that says, "A non ref-returning property or indexer may not be used as an out or ref value." There is an easy fix for this. 

private BindingList<string> _Area = new BindingList<string>();
public BindingList<string> Area
{
    get => _Area;
    set => _Area = SetField<BindingList<string>>(value);
}

//...

public event PropertyChangedEventHandler PropertyChanged;

protected void SetField<T>(T value, [CallerMemberName] string propertyName = null)
{
    PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    return value;
}

ProgrammingLinks/INotifyPropertyChanged (last edited 2023-09-14 23:04:09 by scot)