MVVM模式的View与ViewModel的三大通讯方式:Binding Data(实现数据的传递)、Command(实现操作的调用)和Attached Behavior(实现控件加载过程中的操作)。
下面通过一个实例实现MVVM模式的Binding Data通讯
1、创建Model层
Food.cs
namespace BindingDataDemo.Model
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public string Description
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2.创建ViewModel层
FoodViewModel.cs
using System.ComponentModel;
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using BindingDataDemo.Model;
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using System.Collections.ObjectModel;
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namespace BindingDataDemo.ViewModel
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public class FoodViewModel : INotifyPropertyChanged
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private ObservableCollection<Food> _allFood;
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public ObservableCollection<Food> AllFood
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_allFood = new ObservableCollection<Food>();
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NotifyPropertyChanged( "AllFood" );
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Food item0 = new Food() { Name = "西红柿" , IconUri = "Images/Tomato.png" , Type = "Healthy" ,Description= "西红柿的味道不错。" };
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Food item1 = new Food() { Name = "茄子" , IconUri = "Images/Beer.png" , Type = "NotDetermined" , Description = "不知道这个是否好吃。" };
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Food item2 = new Food() { Name = "火腿" , IconUri = "Images/fries.png" , Type = "Unhealthy" , Description = "这是不健康的食品。" };
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Food item3 = new Food() { Name = "三明治" , IconUri = "Images/Hamburger.png" , Type = "Unhealthy" ,Description= "肯德基的好吃?" };
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Food item4 = new Food() { Name = "冰激凌" , IconUri = "Images/icecream.png" , Type = "Healthy" , Description = "给小朋友吃的。" };
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Food item5 = new Food() { Name = "Pizza" , IconUri = "Images/Pizza.png" , Type = "Unhealthy" ,Description= "这个非常不错。" };
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Food item6 = new Food() { Name = "辣椒" , IconUri = "Images/Pepper.png" , Type = "Healthy" , Description = "我不喜欢吃这东西。" };
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System.Windows.MessageBox.Show( "Exception: " + e.Message );
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public event PropertyChangedEventHandler PropertyChanged;
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public void NotifyPropertyChanged( string propertyName)
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if (PropertyChanged != null )
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PropertyChanged( this , new PropertyChangedEventArgs(propertyName));
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3、创建View层
MainPage.xaml
< phone:PhoneApplicationPage |
x:Class = "BindingDataDemo.MainPage"
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xmlns:phone = "clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
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xmlns:shell = "clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
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xmlns:my = "clr-namespace:BindingDataDemo.ViewModel" |
mc:Ignorable = "d" d:DesignWidth = "480" d:DesignHeight = "768"
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FontFamily = "{StaticResource PhoneFontFamilyNormal}"
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FontSize = "{StaticResource PhoneFontSizeNormal}"
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Foreground = "{StaticResource PhoneForegroundBrush}"
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SupportedOrientations = "Portrait" Orientation = "Portrait"
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shell:SystemTray.IsVisible = "True" >
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<!--添加ViewModel层的FoodViewModel类为资源--> |
< phone:PhoneApplicationPage.Resources >
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< my:FoodViewModel x:Key = "food" />
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</ phone:PhoneApplicationPage.Resources >
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< Grid x:Name = "LayoutRoot" Background = "Transparent" >
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< RowDefinition Height = "Auto" />
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< RowDefinition Height = "*" />
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< StackPanel x:Name = "TitlePanel" Grid.Row = "0" Margin = "12,17,0,28" >
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< TextBlock x:Name = "ApplicationTitle" Text = "MY APPLICATION" Style = "{StaticResource PhoneTextNormalStyle}" />
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< TextBlock x:Name = "PageTitle" Text = "数据绑定" Margin = "9,-7,0,0" Style = "{StaticResource PhoneTextTitle1Style}" />
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<!--在Grid控件中将上面定义好的FoodViewModel类资源赋值给DataContent属性,表示Grid控件内使用FoodViewModel类作为上下文数据--> |
< Grid x:Name = "ContentPanel" Grid.Row = "1" Margin = "12,0,12,0" DataContext = "{StaticResource food }" >
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<!--在ListBox控件中绑定FoodViewModel类的AllFood属性,AllFood是ObservableCollection<Food>类型--> |
< ListBox x:Name = "listBox" HorizontalContentAlignment = "Stretch" ItemsSource = "{Binding AllFood}" >
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< StackPanel Orientation = "Horizontal" Background = "Gray" Width = "450" Margin = "10" >
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< Image Source = "{Binding IconUri}" Stretch = "None" />
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< TextBlock Text = "{Binding Name}" FontSize = "40" Width = "150" />
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<!--绑定Food类的Description属性--> |
< TextBlock Text = "{Binding Description}" FontSize = "20" Width = "280" />
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</ phone:PhoneApplicationPage >
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OK!!!!!!!!!!!!!!!!!!!!!!!
备注:实现绑定数据的方法有很多种,原理都大同小异。