如何在ViewModel中设置属性以从模型列表中获取和设置值？

问题描述

我对MVVM还是很陌生，需要一些指导。

我已经设置了以下MVVM，并且在使用时可以正常工作

private Model model = new Model();

但是，我实际上想收集模型。

public ObservableCollection<Model> models = new ObservableCollection<Model>();

我现在还不太清楚是如何使属性返回例如绑定/选定模型的标题。

我无法指定索引，因为我还不知道索引。我正在考虑在视图中添加一个隐藏的组合框，并在加载窗口时创建一个新模型并选择最高索引。但是，如何确保返回正确的属性以及如何对其进行编码？

当前设置

查看

该视图按如下方式绑定到viewmodel。

    <Window.DataContext>
        <this:viewmodel />
    </Window.DataContext>

viewmodel

viewmodel由两个类组成。一个父类，为当前View实现INotifyPropertyChanged和viewmodel。

using System.ComponentModel;

namespace Framework
{
    public abstract class ObservableObject : INotifyPropertyChanged
    {
        #region Events
        public event PropertyChangedEventHandler PropertyChanged;
        #endregion

        #region Implementation
        protected void NotifyPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
                PropertyChanged(this,new PropertyChangedEventArgs(propertyName));
        }
        #endregion
    }
}

using Framework;
using System.Collections.ObjectModel;
using System.Runtime.Serialization;
using System.Windows;

namespace ESL_Master_Suite.Components.Core.Courses
{
    /// <summary>
    /// Interaction logic for Courses.xaml
    /// </summary>
    public partial class Courses : Window
    {
        public Courses()
        {
            InitializeComponent();
        }
    }

    class viewmodel : ObservableObject
    {
        public ObservableCollection<Model> models = new ObservableCollection<Model>();
        //private Model model = new Model();

        #region Fields
        bool skipUpdating = false;
        #endregion

        #region Properties
        public string Title
        {
            get
            {
                return model.title;
            }
            set
            {
                model.title = value;
                NotifyPropertyChanged("Title");
            }
        }
        #endregion
    }

模型/模型周

模型和子模型如下所示。

   class Model
    {
        public string title;
        
        public ObservableCollection<Model_Weeks> weeks = new ObservableCollection<Model_Weeks>();
    }

    class Model_Weeks
    {
        [DataMember(Name = "title")]
        public string title { get; set; }
        [DataMember(Name = "topic")]
        public int topic { get; set; }
    }
}

解决方法

经过大量的努力，我提出了以下解决方案。我不确定这是否是正确的方法，但似乎可行。

我有两个ViewModel和两个模型。

Courses_ViewModel

class Courses_ViewModel : ObservableObject
    {
        public Courses_Model courses_Model;
        public ObservableCollection<Course_ViewModel> course_ViewModels { get; set; }

        public Courses_ViewModel()
        {
            //Deserialize and assign Parent Model to Local Variable
            courses_Model = new Courses_Model();

            //Initialise ChildModel List
            course_ViewModels = new ObservableCollection<Course_ViewModel>();

            //Create ChildViewModels and Add to List
            foreach (Course_Model course in courses_Model.course_Models)
            {
                course_ViewModels.Add(new Course_ViewModel(course));
            }
        }
    }

Course_ViewModel

class Course_ViewModel : ObservableObject
    {
        public Course_Model course_Model { get; set; }

        public Course_ViewModel(Course_Model model)
        {
            course_Model = model;
        }

        public string Title
        {
            get
            {
                return course_Model.title;
            }
            set
            {
                course_Model.title = value;
                NotifyPropertyChanged("Title");
            }
        }
    }

模型

class Courses_Model
    {
        //List of courses
        public List<Course_Model> course_Models { get; set; }

        public Courses_Model()
        {
            //Initialise course_Models List
            course_Models = new List<Course_Model>();

            //Create courses and add to list
            course_Models.Add(new Course_Model { title = "L1" });
            course_Models.Add(new Course_Model { title = "L2" });
            course_Models.Add(new Course_Model { title = "L3" });
            course_Models.Add(new Course_Model { title = "L4" });
            course_Models.Add(new Course_Model { title = "L5" });
        }
    }

    class Course_Model
    {
        public string title;
    }