[C#]DataContext를 Mappings.xaml에서 설정하기

각 UI.xaml에서 DataContext를 설정하지 않고

Mappings.xaml에서 설정하고
DataContext에서 Binding 해서 쓰기

 

기본적인 메커니즘은 MainWindow에 띄울 UI를 갈아 끼우면서 MainWindow의 DataContext를 바꿔주는 느낌인듯?

 

1. Views, ViewModels 폴더를 만들고

 

2. Views/LoginUI.xaml (UserControl)

<UserControl x:Class="WpfApp12.Views.LoginUI"
             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:WpfApp12.Views"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="500">
    <Grid>
        <TextBlock HorizontalAlignment="Left" Height="75" Margin="200,100,0,0"
                   TextWrapping="Wrap" VerticalAlignment="Top" Width="135" Background="#FFEA3434"
                   Text="{Binding Aaa}"
                   />

    </Grid>
</UserControl>

 

3. ViewModels/LoginViewModel

namespace WpfApp12.ViewModels
{
    class LoginViewModel
    {
        public string Aaa { get; set; } = "777777777777";
    }
}

여기까지 내가 보여줄 화면, 화면과 연결할 ViewModel을 만들었음

---

이제부터는 LoginUI.xaml에 LoginViewModel을 DataContext로 인식하도록 설정함

 

1. Mappings.xaml (Resource Dictionary)

여기서 LoginUI.xaml과 LoginViewModel을 연결

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:dataContext="clr-namespace:WpfApp12.ViewModels"
                    xmlns:views="clr-namespace:WpfApp12.Views">
    <DataTemplate DataType="{x:Type dataContext:LoginViewModel}">
        <views:LoginUI />
    </DataTemplate>
</ResourceDictionary>

 

2. App.xaml

여기서 Mappings.xaml 등록

<Application x:Class="WpfApp12.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:WpfApp12"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="/WpfApp12;component/Mappings.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
         
    </Application.Resources>
</Application>

경로에 "component/"는 기본적으로 쓰는건가 봄

 

3. ViewModels/ShellViewModel.cs

using Microsoft.Toolkit.Mvvm.ComponentModel;

namespace WpfApp12.ViewModels
{
    class ShellViewModel : ObservableObject
    {
        private object? _currentDataContext;

        #region Properties
        public object? CurrentDataContext
        {
            get => _currentDataContext;
            set => SetProperty(ref _currentDataContext, value);
        }
        #endregion  // Properties
    }
}

 

4. App.xaml.cs

using System.Windows;
using WpfApp12.ViewModels;

namespace WpfApp12
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        protected override void OnStartup(StartupEventArgs e)
        {
            base.OnStartup(e);

            ShellViewModel shellViewModel = new ShellViewModel();
            shellViewModel.CurrentDataContext = new LoginViewModel();

            var shellWindow = new MainWindow();
            shellWindow.DataContext = shellViewModel;
            shellWindow.ShowDialog();
        }
    }

}

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이거 하고 나니깐.. 그냥 cs파일에서 DataContext를 정해주니까 xaml에서 안정해줘도 됐던거네;;