Caliburn CanExecute即使开火也不工作

Question

尝试用calibre实现简单的验证。所有我想要的是启用/禁用保存按钮基于某些条件。观点:

`<xctk:MaskedTextBox x:Name="pm_personId" cal:Message.Attach="[Event  LostFocus] = [Action CanSave()]" Mask="00-000-000?"/>
<Button Content="Save" x:Name="Save" />`

模型:

 public class PersonModel
    {        
        public String personId { get; set; }        
        public PersonModel() {}
        public PersonModel(String id)
        {
            this.id = personId;
        }
    }

ViewModel:

[ImplementPropertyChanged]
    public class PersonViewModel : Screen
    {
        public PersonModel pm { get; set; }
        public PersonViewModel()
        {
            pm = new PersonModel();
        }
        public bool CanSave()
        {
            MessageBox.Show(pm.personId);
            if (pm.personId != null)
                return true;
            else return false;
        }   
    }

MessageBox以正确的值触发，但按钮未启用。我错过什么了吗?要么我错过了一些与caliburn或它做了太多的魔法。我开始怀疑它最初可能为您节省的时间将在调试中浪费，这只是我的经验。

Answer 1

谢谢@CCamilo，但是你的回答不完整。对于遇到类似问题的其他人，下面是我的最终工作代码:

[ImplementPropertyChanged]
public class PersonModel
    {        
        public String personId { get; set; }        
        public event PropertyChangedEventHandler PropertyChanged;
        public PersonModel() {}
        public PersonModel(String id)
        {
            this.id = personId;
        }
    }
[ImplementPropertyChanged]
    public class PersonViewModel : Screen
    {
        public PersonModel pm { get; set; }
        public PersonViewModel()
        {
            pm = new PersonModel();
            this.pm.PropertyChanged += pm_PropertyChanged;
        }
        void pm_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            NotifyOfPropertyChange(() => CanSave);
        }
        public bool CanSave
        {
            get { return pm.personId != null; }           
        }   
    }

Answer 2

您的错误是与CanSave()方法。它应该是一个属性:

public bool CanSave
{
    get
    {
        if (pm.personId != null)
            return true;
        else return false;
    }
}