Files
OxyPlot/Source/Examples/WPF/WpfExamples/DelegateCommand.cs
2023-09-02 09:24:59 +02:00

104 lines
3.3 KiB
C#

// --------------------------------------------------------------------------------------------------------------------
// <copyright file="DelegateCommand.cs" company="OxyPlot">
// Copyright (c) 2014 OxyPlot contributors
// </copyright>
// <summary>
// Represents a delegate command.
// </summary>
// --------------------------------------------------------------------------------------------------------------------
namespace WpfExamples
{
using System;
using System.Windows.Input;
/// <summary>
/// Represents a delegate command.
/// </summary>
public class DelegateCommand : ICommand
{
/// <summary>
/// The can execute.
/// </summary>
private readonly Func<bool> canExecute;
/// <summary>
/// The execute.
/// </summary>
private readonly Action execute;
/// <summary>
/// Initializes a new instance of the <see cref="DelegateCommand" /> class.
/// </summary>
/// <param name="execute">The execute.</param>
public DelegateCommand(Action execute)
: this(execute, null)
{
}
/// <summary>
/// Initializes a new instance of the <see cref="DelegateCommand" /> class.
/// </summary>
/// <param name="execute">The execute.</param>
/// <param name="canExecute">The can execute.</param>
public DelegateCommand(Action execute, Func<bool> canExecute)
{
if (execute == null)
{
throw new ArgumentNullException("execute");
}
this.execute = execute;
this.canExecute = canExecute;
}
/// <summary>
/// Occurs when changes occur that affect whether or not the command should execute.
/// </summary>
public event EventHandler CanExecuteChanged
{
add
{
if (this.canExecute != null)
{
CommandManager.RequerySuggested += value;
}
}
remove
{
if (this.canExecute != null)
{
CommandManager.RequerySuggested -= value;
}
}
}
/// <summary>
/// Defines the method that determines whether the command can execute in its current state.
/// </summary>
/// <param name="parameter">Data used by the command. If the command does not require data to be passed, this object can be set to <c>null</c>.</param>
/// <returns><c>true</c> if this command can be executed; otherwise, <c>false</c>.</returns>
public bool CanExecute(object parameter)
{
return this.canExecute == null ? true : this.canExecute();
}
/// <summary>
/// Defines the method to be called when the command is invoked.
/// </summary>
/// <param name="parameter">Data used by the command. If the command does not require data to be passed, this object can be set to <c>null</c>.</param>
public void Execute(object parameter)
{
this.execute();
}
/// <summary>
/// Raises the can execute changed.
/// </summary>
public void RaiseCanExecuteChanged()
{
CommandManager.InvalidateRequerySuggested();
}
}
}