我有ObservbleCollection
绑定到列表框。在我将集合作为列表的ItemsSource后,我无法更新我的集合。如果我更新它,程序关闭(没有任何崩溃)。
守则:
我有课:
class MyFile
{
String FileName {get; set;}
ImageSource Ico {get; set;}
}
然后在约束器中运行代码(在InitializeComponents之后)
ObservableCollection<MyFile> filesList = new ObservableCollection<MyFile>();
filesList.Add(new MyFile { Name = "bar.doc", Ico = null } // Work Fine
filesList.Add(new MyFile { Name = "foo.txt", Ico = null } // Work Fine
files.ItemsSource = filesList;
filesList.Add(new MyFile { Name = "try.txt", Ico = null } // EXIT FROM PROGRAM
我的课程有什么问题?
修改
刚刚使用null测试它而不是GetIcon
答案 0 :(得分:0)
ObservableCollection的任务是向听众宣布更改(添加,删除......)。因此ObservableCollection
没有任何问题,并将其绑定为ListBox的ItemsSource
,不会使其无法编辑。 GetIcon
方法一定有问题(例如尝试重新打开未正确关闭的相同图像)
要了解这个想法是否正确,请尝试以下方法:
ObservableCollection<MyFile> filesList = new ObservableCollection<MyFile>();
filesList.Add(new MyFile { Name = "bar.doc", Ico = GetIcon(".doc") }
//filesList.Add(new MyFile { Name = "foo.txt", Ico = GetIcon(".txt") } // Comment this line
files.ItemsSource = filesList;
filesList.Add(new MyFile { Name = "try.txt", Ico = GetIcon(".txt") }
如果你想看到这个bug。我建议你在按钮的单击事件中复制这些行(而不是在构造函数中)然后运行你的应用程序。
答案 1 :(得分:0)
以下是使用DependencyPropery绑定ObservableCollection的小样本。我希望它能帮助您以这种方式进行DataBinding。
XAML
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Name="MyWindow"
Title="MainWindow">
<Grid>
<ListBox ItemsSource="{Binding MyList, ElementName=MyWindow, Mode=TwoWay}">
</ListBox>
</Grid>
</Window>
背后的代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Threading;
using System.Collections.ObjectModel;
namespace WpfApplication1
{
/// <summary>
/// Logica di interazione per MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public static readonly DependencyProperty MyListProperty = DependencyProperty.Register("MyList", typeof(ObservableCollection<string>), typeof(MainWindow));
public ObservableCollection<string> MyList
{
get
{
return (ObservableCollection<string>)GetValue(MyListProperty);
}
set
{
SetValue(MyListProperty, value);
}
}
public MainWindow()
{
InitializeComponent();
MyList = new ObservableCollection<string>() { "a", "b" };
MyList.Add("c");
}
}
}