數據綁定類屬性與網格高度

Question

我有以下類：

public class Height 
{ 
    public GridLength GridHeight = new GridLength(200); 
} 

我想這個字段綁定到從網格第一行高：

<Grid.RowDefinitions> 
     <RowDefinition Height="{Binding Path=GridHeight, Mode=OneWay}"></RowDefinition> 
     <RowDefinition></RowDefinition> 
    </Grid.RowDefinitions> 

我也宣佈在DataContext ：

public MainWindow() 
    { 
     DataContext = new Height(); 
    } 

但是根本沒有交互。我看不出有什麼不對。 非常感謝，如果有人可以解釋如何將一個類屬性數據綁定到行Height屬性。

Answer 1

綁定作品只有只有當你當你更新的GridHeight電網自動更新它的價值

public class Height:INotifyPropertyChanged 
{ 
    GridLength _gridheight = new GridLength(200); 
    public GridLength GridHeight 
      { 
        get{ 
          return _gridheight; 
         } 

        set{ 
          if(_gridheight==value) 
           return; 

          _gridheight=value; 
          NotifyPropertyChanged("GridHeight") 
         } 

     } 

    public event PropertyChangedEventHandler PropertyChanged; 

    private void NotifyPropertyChanged(string propertyName = "") 
    { 
     if (PropertyChanged != null) 
     { 
      PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); 
     } 
    } 

} 

價值實現INotifyPropertyChanged接口

所以這裏屬性不會領域，和更新

Answer 2

您需要製作GridHeight屬性，而不是字段。

如果您希望更新Height類，您可能還需要實現INotifyPropertyChanged。

public class Height 
{ 
    public Height() 
    { 
     this.GridHeight = new GridLength(200); 
    } 

    // Needs to be a property for data binding 
    public GridLength GridHeight { get; set; } 
}