一步一步学习MVVM一 查询篇

关于MVVM模式概念就不讲了，网上一大堆，而且超详细。 先描述一下整体解决方案：把服务器信息从服务器端取出来显示在客户端，

Model层负责取数据并序列化成对象，ViewModel负责绑定到View,

效果图：

 

Model层负责数据

 

 

实体Server实现

INotifyPropertyChanged接口，当属性改变时通知界面。

 

 1   #region ip
 2          private  string _ip;
 3 
 4          public  string IP
 5         {
 6              get {  return _ip; }
 7              set
 8             {
 9                  if (_ip != value)
10                 {
11                     _ip = value;
12                     OnPropertyChanged( " IP ");
13                 }
14             }
15         }
16          #endregion
17 
18          #region 名称
19          private  string _Name;
20 
21          public  string Name
22         {
23              get {  return _Name; }
24              set
25             {
26                  if (_Name != value)
27                 {
28                     _Name = value;
29                     OnPropertyChanged( " Name ");
30                 }
31 
32             }
33         }
34          #endregion
35 
36          public  event PropertyChangedEventHandler PropertyChanged;
37 
38          private  void OnPropertyChanged( string propertyName)
39         {
40              if (PropertyChanged !=  null)
41                 PropertyChanged( this,  new PropertyChangedEventArgs(propertyName));
42         }

 

取Server数据的方法，实际可改为从WCF中取数据，

 

1          private ObservableCollection<Server> serverList;
2          public ObservableCollection<Server> GetServerList()
3         {
4             serverList =  new ObservableCollection<Server>();
5             serverList.Add( new Server { IP= " 192.168.1.1 ",Name= " 张三的电脑 "});
6             serverList.Add( new Server { IP =  " 192.168.1.2 ", Name =  " 李四的电脑 " });
7             serverList.Add( new Server { IP =  " 192.168.1.1 ", Name =  " 王五的电脑 " });
8              return serverList;
9         }

 

所有的业务集中在ViewModel里面，提供View绑定需要的各种属性和集合。

 

 1      public  class ServerViewModel:INotifyPropertyChanged
 2     {
 3          private ServerModel sm;
 4          private Server currentServer;
 5          public Server CurrentServer
 6         {
 7              get {  return currentServer; }
 8              set
 9             {
10                 CurrentServer = value;
11                  this.OnPropertyChanged( " CurrentServer ");
12             }
13         }
14 
15          public ServerViewModel()
16         { 
17             sm= new ServerModel();
18             serverList = sm.GetServerList();
19         }
20 
21          private ObservableCollection<Server> serverList;
22          public ObservableCollection<Server> ServerList 
23         {
24              get {  return serverList; }
25              set 
26             { 
27                 serverList = value;
28                  this.OnPropertyChanged( " ServerList ");
29             }
30         }
31 
32          public  event PropertyChangedEventHandler PropertyChanged;
33 
34          private  void OnPropertyChanged( string propertyName)
35         {
36              if (PropertyChanged !=  null)
37                 PropertyChanged( this,  new PropertyChangedEventArgs(propertyName));
38         }
39     }

 

View中代码最简洁：

 

         private ServerViewModel svm;
         public MainPage()
        {
            InitializeComponent();
            svm =  new ServerViewModel();
             this.DataContext = svm;
        }

 

Demo下载