WPFのスライダーのサンプルコードを使いデータバインディングの使い方を確認する – その2

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>net10.0-windows</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
    <UseWPF>true</UseWPF>
  </PropertyGroup>

</Project>

using System.Windows;
using System.Windows.Input;

static  partial class AppCommands
{
    public static void Bind(
        Window w,
        ICommand cmd,
        ExecutedRoutedEventHandler exec,
        CanExecuteRoutedEventHandler? can = null)
    {
        w.CommandBindings.Add(
            new CommandBinding(
                cmd,
                exec,
                can ?? ((_, e) => e.CanExecute = true)
            ));
    }


}

using System.Windows;
using System.Windows.Input;

namespace SliderDemo2;

static  partial class AppCommands
{
    // アプリ専用コマンド
    public static readonly RoutedUICommand Reset =
        new RoutedUICommand(
            "Reset",
            "Reset",
            typeof(AppCommands));
}

public partial class MainWindow : Window
{
    MainWindowViewModel VM => (MainWindowViewModel)DataContext;

    public MainWindow()
    {
        InitializeComponent();

        DataContext = new MainWindowViewModel
        {
            SliderValue = 50
        };

        // Reset コマンド登録
        CommandBindings.Add(
            new CommandBinding(
                AppCommands.Reset,
                Reset_Executed,
                Reset_CanExecute));
    }

    void Reset_Executed(object sender, ExecutedRoutedEventArgs e)
    {
        VM.SliderValue = 0;
    }

    void Reset_CanExecute(object sender, CanExecuteRoutedEventArgs e)
    {
        e.CanExecute = VM.SliderValue != 0;
    }
}

using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace SliderDemo2;

public class MainWindowViewModel : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler? PropertyChanged;

    void Raise([CallerMemberName] string? name = null)
        => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));

    int _sliderValue;
    public int SliderValue
    {
        get => _sliderValue;
        set
        {
            if (_sliderValue == value) return;
            _sliderValue = value;
            Raise();
        }
    }

    public int SliderMin { get; set; } = 0;
    public int SliderMax { get; set; } = 200;
    public bool IsSliderEnabled { get; set; } = true;
}

<Window x:Class="SliderDemo2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:SliderDemo2"
        Title="Slider Demo"
        Height="260"
        Width="500">

    <Grid Margin="20">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>

        <TextBlock FontSize="28"
                   HorizontalAlignment="Center"
                   Text="{Binding SliderValue,
                                  StringFormat=現在値: {0:F0}}"/>

        <Slider Grid.Row="1"
                Height="30"
                Minimum="{Binding SliderMin}"
                Maximum="{Binding SliderMax}"
                Value="{Binding SliderValue,
                                Mode=TwoWay,
                                UpdateSourceTrigger=PropertyChanged}"
                IsEnabled="{Binding IsSliderEnabled}" />

        <Button Grid.Row="2"
                Margin="0,16,0,0"
                Padding="6"
                FontSize="16"
                Command="{x:Static local:AppCommands.Reset}"
                Content="リセット"/>
    </Grid>
</Window>