當我單擊UserControl內部的按鈕時，如何更改MainWindow的內容？

Question

我剛剛開始學習MVVM，當我想從UserControl內部單擊按鈕更改MainWindow的內容時，我想知道最佳實踐是什么。

這是UserControl，其中包含我將要單擊的按鈕。 當我單擊生成的IconButton時，我希望能夠將MainGrid更改為包含我的IconModel信息的網格。

為了澄清起見，我希望網格顯示圖標的名稱，描述，用戶名，密碼，並具有一個使用Path可以打開程序或網站的按鈕。 Icon類位於下面發布的IconModel.cs中。

IconView.xaml

    <UserControl x:Class="ProgramManager.Views.IconView"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:ProgramManager"
             xmlns:viewModel="clr-namespace:ProgramManager.ViewModel"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">
    <UserControl.DataContext>
        <viewModel:IconViewModel/>
    </UserControl.DataContext>
    <ScrollViewer HorizontalScrollBarVisibility="Disabled" VerticalScrollBarVisibility="Auto">
        <ItemsControl ItemsSource="{Binding Path = Icons}">
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Button Name="IconButton" Style="{StaticResource IconButtonStyle}" Content="{Binding Path = Initial, Mode = OneWay}" Click="Button_Click">
                        <Button.ToolTip>
                            <ToolTip Content="{Binding Path = Name, Mode = TwoWay}"/>
                        </Button.ToolTip>
                    </Button>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </ScrollViewer>
</UserControl>

MainWindow.xaml

    <Window x:Class="ProgramManager.MainWindow"
        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:ProgramManager"
        xmlns:views="clr-namespace:ProgramManager.Views"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="1*"/>
        </Grid.ColumnDefinitions>
        <Grid Name="MainGrid" Grid.Column="1">

        </Grid>
    </Grid>
</Window>

作為參考，這是我的IconModel和IconViewModel類。

IconModel.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Xml.Serialization;

namespace ProgramManager.Model
{

    public class IconModel { }

    [XmlRoot(ElementName = "Icons", IsNullable = true, DataType = "string")]
    [XmlType(AnonymousType = true)]
    [XmlInclude(typeof(ProgramIcon))]
    [XmlInclude(typeof(WebsiteIcon))]
    public class Icon : IComparable<Icon>, IComparer<Icon>, INotifyPropertyChanged
    {
        private string name;
        private string description;
        private string path;
        private string username;
        private string password;

        [XmlElement("Name")]
        public string Name
        {
            get { return name; }
            set
            {
                if (name != value)
                {
                    name = value;
                    RaisePropertyChanged("Name");
                }
            }
        }

        [XmlElement("Description")]
        public string Description
        {
            get { return description; }
            set
            {
                if (description != value)
                {
                    description = value;
                    RaisePropertyChanged("Description");
                }
            }
        }

        [XmlElement("Path")]
        public string Path
        {
            get { return path; }
            set
            {
                if (path != value)
                {
                    path = value;
                    RaisePropertyChanged("Path");
                }
            }
        }

        [XmlElement("Username")]
        public string Username
        {
            get { return username; }
            set
            {
                if (username != value)
                {
                    username = value;
                    RaisePropertyChanged("Username");
                }
            }
        }

        [XmlElement("Password")]
        public string Password
        {
            get { return password; }
            set
            {
                if (password != value)
                {
                    password = value;
                    RaisePropertyChanged("Password");
                }
            }
        }

        public string Initial {
            get
            {
                return this.Name.Substring(0, 1).ToUpper();
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        private void RaisePropertyChanged(string property)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(property));
            }
        }

        public int Compare(Icon x, Icon y)
        {
            return (x.Equals(null) || y.Equals(null)) ? 0 : x.CompareTo(y);
        }

        public int CompareTo(Icon other)
        {
            return string.Compare(this.Name, other.Name);
        }
    }

    public class ProgramIcon : Icon { }
    public class WebsiteIcon : Icon { }
}

IconViewModel.cs

using ProgramManager.Helpers;
using ProgramManager.Model;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.IO;

namespace ProgramManager.ViewModel
{
    public class IconViewModel : INotifyPropertyChanged
    {
        private static readonly List<Icon> iconsList;
        private ObservableCollection<Icon> icons;
        public ObservableCollection<Icon> Icons
        {
            get { return icons; }
            set
            {
                if (icons != value)
                {
                    icons = value;
                    RaisePropertyChanged("Icons");
                }
            }
        }
        public event PropertyChangedEventHandler PropertyChanged;

        private void RaisePropertyChanged(string property)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(property));
            }
        }

        public IconViewModel()
        {
            LoadIcons();
        }

        static IconViewModel()
        {
            if (!Directory.Exists(Constants.ResourcesDirectory))
            {
                Directory.CreateDirectory(Constants.ResourcesDirectory);
            }

            iconsList = XmlDataStorage.GetList<Icon>(Constants.IconsFilePath);
        }

        public void LoadIcons()
        {
            ObservableCollection<Icon> icons = new ObservableCollection<Icon>();

            foreach(var icon in iconsList)
            {
                icons.Add(icon);
            }

            Icons = icons;
        }

        public void AddIcon(Icon icon)
        {
            iconsList.Add(icon);
            iconsList.Sort();

            XmlDataStorage.SaveToXml(Constants.IconsFilePath, iconsList);

            LoadIcons();
        }
    }
}

我嘗試從IconView.xaml訪問MainWindow中的IconButton，但似乎無法弄清楚該如何做。

任何幫助表示贊賞，謝謝！

Answer 1

1. 您可以訪問諸如Application.Current.MainWindow類的主窗口。

2. 對於MVVM解決方案，您可以做一些類似的事情（采取主意，我沒有對此進行編譯）：

在MainWindow.xaml中：

<Label DataContext="{IconViewModel }" Content={Binding YourProperty}/>

我的意思是，您可以將標簽的數據上下文設置為IconViewModel，並將其綁定到IconViewModel類的屬性。

3. 第三個選項是在IconViewModel內創建一個事件，然后單擊按鈕以調用該事件，主窗口將預訂該事件。

Answer 2

為什么不將IconView.xaml更改為ContentTemplate？並且將IconButton綁定依賴項屬性，以便可以在任何地方操作IconButton，包括MainWindow。