是否有 RelayCommand 版本,因为 CommandManager 在 win8 Metro 应用程序中不可用?
问问题
5136 次
3 回答
4
这里有一个版本。
using System;
using System.Diagnostics;
#if METRO
using Windows.UI.Xaml.Input;
using System.Windows.Input;
#else
using System.Windows.Input;
#endif
namespace MyToolkit.MVVM
{
#if METRO
public class RelayCommand : NotifyPropertyChanged, ICommand
#else
public class RelayCommand : NotifyPropertyChanged<RelayCommand>, ICommand
#endif
{
private readonly Action execute;
private readonly Func<bool> canExecute;
public RelayCommand(Action execute)
: this(execute, null) { }
public RelayCommand(Action execute, Func<bool> canExecute)
{
if (execute == null)
throw new ArgumentNullException("execute");
this.execute = execute;
this.canExecute = canExecute;
}
bool ICommand.CanExecute(object parameter)
{
return CanExecute;
}
public void Execute(object parameter)
{
execute();
}
public bool CanExecute
{
get { return canExecute == null || canExecute(); }
}
public void RaiseCanExecuteChanged()
{
RaisePropertyChanged("CanExecute");
if (CanExecuteChanged != null)
CanExecuteChanged(this, new EventArgs());
}
public event EventHandler CanExecuteChanged;
}
public class RelayCommand<T> : ICommand
{
private readonly Action<T> execute;
private readonly Predicate<T> canExecute;
public RelayCommand(Action<T> execute)
: this(execute, null)
{
}
public RelayCommand(Action<T> execute, Predicate<T> canExecute)
{
if (execute == null)
throw new ArgumentNullException("execute");
this.execute = execute;
this.canExecute = canExecute;
}
[DebuggerStepThrough]
public bool CanExecute(object parameter)
{
return canExecute == null || canExecute((T)parameter);
}
public void Execute(object parameter)
{
execute((T)parameter);
}
public void RaiseCanExecuteChanged()
{
if (CanExecuteChanged != null)
CanExecuteChanged(this, new EventArgs());
}
public event EventHandler CanExecuteChanged;
}
}
于 2012-09-18T23:49:42.897 回答
1
如果 Metro 中提供了 ICommand,则没有实现,尽管有几个版本可用,例如CodeProject上的这个。
于 2012-09-18T23:49:51.860 回答
0
Prism for Windows Store 应用程序现在可用,其中包含 DelegateCommand(实现 ICommand)以及 OnPropertyChanged 的实现。
于 2013-07-05T03:34:45.323 回答