我创建了一个小示例来演示我遇到的问题。
首先我的课:
public class DisplayRow : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
private int?[] values;
private string title;
public string Title
{
get { return title; }
set
{
title = value;
if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("Title"));
}
}
public int?[] Values
{
get { return values; }
set
{
values = value;
if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("Values[]"));
}
}
public DisplayRow()
{
Values = new int?[6];
}
}
问题在于 Values 属性,因为它是一个数组。当数组中的元素更新时,我不确定如何正确调用 INotifyPropertyChanged。
这是我的xml:
<Window x:Class="WpfApplication5.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="300" Width="300">
<Grid>
<ListBox x:Name="MyListBox" Margin="0,0,0,65">
<ListBox.ItemTemplate>
<DataTemplate>
<WrapPanel>
<TextBlock Text="{Binding Path=Title}" />
<TextBlock Text="{Binding Path=Values[0]}" Margin="5,0,0,0" />
<TextBlock Text="{Binding Path=Values[1]}" Margin="5,0,0,0" />
<TextBlock Text="{Binding Path=Values[2]}" Margin="5,0,0,0" />
<TextBlock Text="{Binding Path=Values[3]}" Margin="5,0,0,0" />
<TextBlock Text="{Binding Path=Values[4]}" Margin="5,0,0,0" />
<TextBlock Text="{Binding Path=Values[5]}" Margin="5,0,0,0" />
</WrapPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<Button Height="23" Margin="27,0,0,23" Name="button1" VerticalAlignment="Bottom" HorizontalAlignment="Left" Width="74" Click="button1_Click">Button</Button>
</Grid>
</Window>
以及背后的代码:
public partial class Window1 : Window
{
private readonly ObservableCollection<DisplayRow> displayRows = new ObservableCollection<DisplayRow>();
public Window1()
{
InitializeComponent();
displayRows.Add(new DisplayRow {Title = "Item 1", Values = new int?[] {1, 2, 3, 4, 5, 6}});
displayRows.Add(new DisplayRow {Title = "Item 2", Values = new int?[] {7, 8, 9, 10, 11, 12}});
displayRows.Add(new DisplayRow {Title = "Item 3", Values = new int?[] {13, 14, 15, 16, 17, 18}});
MyListBox.ItemsSource = displayRows;
}
private void button1_Click(object sender, RoutedEventArgs e)
{
foreach (DisplayRow row in displayRows)
{
row.Values[0] = 99;
}
}
}
当我单击按钮时,它会更改第一行的值,但该更改不会反映在 UI 上。如果我更改 Title 属性,则标题会正确更新。
有什么想法可以调用 INotifyPropertyChanged 以便它了解数组元素已更新?