MVVM框架-MVVMLight

项目URL：http://www.mvvmlight.net/

一、安装MVVMLight

在NuGet程序包中搜索MVVMLight，然后安装。

二、使用

 安装完MVVMLight后项目中会自动生成ViewModel目录，并且目录中会生成ViewModelLocator.cs文件

App.xaml会自动添加代码，注册全局变量Locator

    <Application.Resources>
        <ResourceDictionary>
            <vm:ViewModelLocator x:Key="Locator" d:IsDataSource="True" xmlns:vm="clr-namespace:WpfTest.ViewModel" />
        </ResourceDictionary>
    </Application.Resources>

建立Model目录放置model类，View目录放置view类

 在Model下添加PeopleModel.cs，继承ObservableObject类，ObservableObject实现了INotifyPropertyChanged接口，所有PeopleModel的属性改变可以通知控件绑定属性

    public class PeopleModel : ObservableObject
    {
        private string name = "";
        public string Name { get => name; set => Set(ref name, value); }
    }

 在ViewModel下添加PeopleViewModel.cs，继承ViewModelBase类，ViewModelBase类继承ObservableObject类

    public class PeopleViewModel : ViewModelBase
    {
        private PeopleModel people = new PeopleModel();
        public PeopleModel People { get => people; set => Set(ref people, value); }
//不带参数命令
        public ICommand CmdUpdateName
        {
            get
            {
                return new RelayCommand(new Action(() =>
                {
                    People.Name = "无参数";
                }));
            }
        }
//带参数命令
        public ICommand CmdUpdateName1
        {
            get
            {
                return new RelayCommand<object>(new Action<object>(t =>
                {
                    People.Name = System.Convert.ToString(t);
                }));
            }
        }
    }　

在ViewModelLocator.cs里注册PeopleViewModel元素

    /// <summary>
    /// This class contains static references to all the view models in the
    /// application and provides an entry point for the bindings.
    /// </summary>
    public class ViewModelLocator
    {
        /// <summary>
        /// Initializes a new instance of the ViewModelLocator class.
        /// </summary>
        public ViewModelLocator()
        {
            ServiceLocator.SetLocatorProvider(() => SimpleIoc.Default);

            ////if (ViewModelBase.IsInDesignModeStatic)
            ////{
            ////    // Create design time view services and models
            ////    SimpleIoc.Default.Register<IDataService, DesignDataService>();
            ////}
            ////else
            ////{
            ////    // Create run time view services and models
            ////    SimpleIoc.Default.Register<IDataService, DataService>();
            ////}

            SimpleIoc.Default.Register<MainViewModel>();
            SimpleIoc.Default.Register<PeopleViewModel>();
        }

        public MainViewModel Main
        {
            get
            {
                return ServiceLocator.Current.GetInstance<MainViewModel>();
            }
        }

        public PeopleViewModel PeopleVM
        {
            get
            {
                return ServiceLocator.Current.GetInstance<PeopleViewModel>();
            }
        }

        public static void Cleanup()
        {
            // TODO Clear the ViewModels
        }
    }　　

在View目录下添加PeopleWindow窗体，并给window的DataContext属性绑定PeopleVM元素

<Window x:Class="WpfTest.View.PeopleWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfTest.View"
        mc:Ignorable="d"
        Title="PeopleWindow" Height="450" Width="800"
        DataContext="{Binding Source={StaticResource Locator}, Path=PeopleVM}">
    <Grid>
        <Button Command="{Binding CmdUpdateName}" Content="无参数" HorizontalAlignment="Left" Margin="10,31,0,0" VerticalAlignment="Top" Width="75"/>
        <Button Command="{Binding CmdUpdateName1}" CommandParameter="有参数" Content="有参数" HorizontalAlignment="Left" Margin="10,69,0,0" VerticalAlignment="Top" Width="75"/>
        <Label Content="{Binding People.Name}" HorizontalAlignment="Left" Margin="135,33,0,0" VerticalAlignment="Top" RenderTransformOrigin="-1.663,-1.363"/>
    </Grid>
</Window>

 界面效果：

（1）点击无参数按钮：

（2）点击有参数按钮

参考：

https://www.cnblogs.com/manupstairs/p/4890300.html 里面有对MVVMLight比较详细的解释