如何创建此共享的类成员或属性 [英] How to create this shared class member or property

问题描述

我有XAML引用的以下类。该类带有大量属于按钮的附加属性和行为，因此它位于UI方面。

I have the following class that is referenced by my XAML. This class sits with a bunch of attached properties and behaviors that belong to buttons, so it is on the UI side of things.

其中一些行为设置了current_cell_match，并且每个行为都有其自己的类，这就是为什么我将其置于静态类中以便可以共享。 / p>

A few of these behaviors set current_cell_match and each of these behaviors has it's own class, that is why I placed it into a static class so that it can be shared.

public static class SearchVariables
{
    public static DataGridCellInfo current_cell_match;

    public static void setCurrentCell(Object dgi, DataGridColumn dgc, string property_name)
    {
        current_cell_property = property_name;
        if (property_name == null)
            current_cell_match = new DataGridCellInfo();
        else
            current_cell_match = new DataGridCellInfo(dgi, dgc);
    }
}

我不确定current_cell_match是否应为成员，属性或附加财产。我真的不需要将其用作任何UI控件上的属性，因此我在考虑前两个。

I am unsure if current_cell_match should be a member, property or attached property. I don't really need to use it as a property on any of the UI controls so I'm thinking one of the first two.

我将它与MultiBinding转换器一起使用，因此我需要知道它的值何时更改。因此，我倾向于使用具有PropertyChangedEventHandler的属性。但是静态类没有实例，因此这将不起作用，没有 this。

I will be using it with a MultiBinding converter, so I need to know when it's value changes. So I'm leaning towards a property with a PropertyChangedEventHandler. However static classes don't have an instance, so this won't work, there is no 'this'.

public event PropertyChangedEventHandler PropertyChanged;

private void RaisePropertyChanged(string propertyName)
{
    if (PropertyChanged != null)
        PropertyChanged(this, new System.ComponentModel.PropertyChangedEventArgs(propertyName));
}

这是我最后要使用的多重绑定：

Here is the multibinding I will use in the end:

<Setter Property="helpers:SearchBehaviours.IsTextMatchFocused">
    <Setter.Value>
        <MultiBinding Converter="{StaticResource SelectedSearchValueConverter}" FallbackValue="False">
            <Binding Path="(helpers:SearchBehaviours.IsFindPopupOpen)" RelativeSource="{RelativeSource Self}"/>
            <Binding Source="{x:Static helpers:SearchVariables.current_cell_match}"/>
        </MultiBinding>
    </Setter.Value>
</Setter>

有人可以帮我构建current_cell_match吗？

Could someone help me construct current_cell_match please?

推荐答案

关于但是，静态类没有实例，所以它不会起作用，没有'this'。您可以执行以下操作：

Regarding "However static classes don't have an instance, so this won't work, there is no 'this'." you can do the following:

public event PropertyChangedEventHandler PropertyChanged;

private void RaisePropertyChanged(string propertyName)
{
    if (PropertyChanged != null)
        PropertyChanged(typeof(this), new System.ComponentModel.PropertyChangedEventArgs(propertyName));
}

这将向PropertyChanged侦听器指示发件人不是实例，

This will indicate to the PropertyChanged-listeners that the sender is not an instance, and the listeners will still be able to see the sender type.

要更新视图，您需要实现INotifyPropertyChanged接口。但这在使用静态属性时可能会非常棘手。相反，我建议实现单例模式，并使您的静态属性成为正常属性。静态类和单例模式之间的差异不是很大。因此，这可能是您要走的路。

To update the view you need to implement the interface INotifyPropertyChanged. But this can be pretty tricky when using static properties. Instead I would suggest to implement the singleton pattern, and make your static properties "normal" properties. The differences between a static class and the singleton pattern are not that big. So this might be the way for you to go.

这里是一个示例。 Xaml：

Here is an example. Xaml:

<Binding Source="{x:Static local:MyClass.Instance}" Path="MyInt" />

代码：

public class MyClass : INotifyPropertyChanged
{
    private Random random;

    private int m_MyInt;
    public int MyInt
    {
        get
        {
            return m_MyInt;
        }
        set
        {
            if ( m_MyInt == value )
            {
               return;
            }

            m_MyInt = value;
            NotifyPropertyChanged();
        }
    }

    private static MyClass m_Instance;
    public static MyClass Instance
    {
        get
        {
            if ( m_Instance == null )
            {
                m_Instance = new MyClass();
            }

            return m_Instance;
         }
    }

    private MyClass()
    {
        random = new Random();
        m_MyInt = random.Next( 0, 100 );

        Timer timer = new Timer();
        timer.Interval = 1000;
        timer.Elapsed += timer_Elapsed;
        timer.Start();
    }

    private void timer_Elapsed( object sender, ElapsedEventArgs e )
    {
        MyInt = random.Next( 0, 100 );
    }

    #region INotifyPropertyChanged Members

    public event PropertyChangedEventHandler PropertyChanged;

    private void NotifyPropertyChanged( [CallerMemberName] String propertyName = "" )
    {
        if ( PropertyChanged != null )
        {
            PropertyChanged( this, new PropertyChangedEventArgs( propertyName ) );
        }
    }

    #endregion
}

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