Silverlight 3 - 如何“刷新”DataGrid内容?

时间:2009-12-01 14:37:12

标签: c# silverlight datagrid

我有以下风景:

1    using System;
2    using System.Windows;
3    using System.Windows.Controls;
4    using System.Windows.Documents;
5    using System.Windows.Ink;
6    using System.Windows.Input;
7    using System.Windows.Media;
8    using System.Windows.Media.Animation;
9    using System.Windows.Shapes;
10   using System.Collections.Generic;
11   
12   namespace refresh
13   {
14      public partial class MainPage : UserControl
15      {
16          
17          List c = new List();
18   
19          public MainPage()
20          {
21              // Required to initialize variables
22              InitializeComponent();
23              c.Add(new Customer{ _nome = "Josimari", _idade = "29"});
24              c.Add(new Customer{_nome = "Wesley", _idade = "26"});
25              c.Add(new Customer{_nome = "Renato",_idade = "31"});    
26              
27              this.dtGrid.ItemsSource = c;
28          }
29   
30          private void Button_Click(object sender, System.Windows.RoutedEventArgs e)
31          {
32              c.Add(new Customer{_nome = "Maiara",_idade = "18"});
33          }
34          
35      }
36      
37      public class Customer
38      {
39          public string _nome{get; set;}
40          public string _idade{get; set;}
41      }
42   }

其中,dtGrid是我的DataGrid控件......

问题是:如何在我的列表中再添加一个寄存器后更新UI。

我得解决它将DataGrid的Item Source设置为“”,然后再次设置为Customer对象列表,如下所示:

1    private void Button_Click(object sender, System.Windows.RoutedEventArgs e)
2    
3    {
4    
5    c.Add(new Customer{_nome = "Maiara",_idade = "18"});
6    
7    this.dtGrid.ItemsSource="";
8    
9    this.dtGrid.ItemsSource=c;
10   
11   }
12   

在更新,更改或删除列表中的项目后,有没有办法让UI更新或datagrid的itemsSource自动刷新?

谢谢,

Josimari Martarelli

1 个答案:

答案 0 :(得分:8)

我建议查看绑定,INotifyPropertyChanged,DataContexts和ObservableCollection。

  1. 将您的List更改为ObservableCollection。仅此一点可能会解决您的一些问题......因为ObservableCollection比简单List

  2. 更强大
  3. 但是,如果你想解决更多类似的问题,你会考虑通过Xaml DataGrid

  4. <DataGrid... ItemsSource="{Binding MyList}">绑定到对象列表
  5. 要将DataGrid绑定到List,您需要设置视图的DataContext。放置在构造函数中可以很简单:this.DataContext = this;设置DataContext告诉视图在查看Binding语句时查找数据的位置

  6. 然后,为了解决您所拥有的问题(更改某些内容不会刷新视图),您将在类上实现INotifyPropertyChanged接口。这将允许后面的代码向视图发送通知,以便在发生更改时告知它。

  7. 以下是实现此目的的C#代码:

    public partial class MainPage : UserControl, INotifyPropertyChanged
    {
        private ObservableCollection<Customer> _MyList = 
            new ObservableCollection<Customer>();
        public ObservableCollection<Customer> MyList
        {
            get { return _MyList; }  
        } 
    
        public MainPage()
        {                      
            InitializeComponent();
    
            this.DataContext = this;
    
            MyList.Add(new Customer{ _nome = "Josimari", _idade = "29"});
            MyList.Add(new Customer{_nome = "Wesley", _idade = "26"});
            MyList.Add(new Customer{_nome = "Renato",_idade = "31"});
    
            OnPropertyChanged("MyList"); // This only works if you use bindings.
        }
    
        private void Button_Click(object sender, System.Windows.RoutedEventArgs e)
        {
            MyList.Add(new Customer{_nome = "Maiara",_idade = "18"});   
    
            OnPropertyChanged("MyList"); // This only works if you use bindings.
        }
    
        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged( string propertyName )
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        } 
    }