在运行时将窗口的最小宽度和高度设置为嵌入式绑定控件的最小值

Question

我有一个Window：

<Window x:Class="ClientApp.Views.ModalWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="" Height="332" Width="536" >

    <Grid VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Margin="0">
        <ContentControl Content="{Binding Path=InlaidViewModel}" Margin="0" 
            HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
    </Grid>
</Window>

在运行时，ContentControl 上的 InlaidViewModel 绑定是根据应用程序中的其他值设置的。如何在绑定时将Window 上的MinHeight 和MinWidth 设置为嵌入式控件上的相同值？例如：

<Window x:Class="Roryap.BillCalendar.ClientApp.Views.ModalWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="" Height="332" Width="536" 
        MinHeight="{Binding **what goes here**}" MinWidth="{Binding **what goes here**}">

我知道我可以为 Window 的底层视图模型添加属性以绑定到这些值，但我不确定我是否想这样做，这更像是一种好奇心。

问题是：如果我不想为我的窗口拥有MinHeight 和MinWidth 的视图模型属性，有没有办法从运行时绑定的嵌入式控件继承这些值？

Answer 1

如果我正确理解您的要求，您应该能够像这样绑定到 ControlControl 内容的 MinHeight 和 MinWidth 属性：

<Window x:Class="ClientApp.Views.ModalWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="" Height="332" Width="536"
    MinHeight="{Binding Path=Content.MinHeight, ElementName=cc}"
    MinWidth="{Binding Path=Content.MinWidth, ElementName=cc}">

<Grid VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Margin="0">
    <ContentControl x:Name="cc" Content="{Binding Path=InlaidViewModel}" Margin="0" 
        HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</Grid>

这假定 InlaidViewModel 属性返回的任何对象都具有 System.Double 类型的 MinHeight 和 MinWidth 属性：

public partial class ModalWindow : Window
{
    private readonly WindowViewModel _viewModel;
    public ModalWindow()
    {
        InitializeComponent();
        _viewModel = new WindowViewModel();
        DataContext = _viewModel;
        Loaded += async (s, e) =>
        {
            _viewModel.InlaidViewModel = new InlaidViewModel();
            //wait 2 seconds before setting the MinHeight property
            await Task.Delay(2000);
            _viewModel.InlaidViewModel.MinHeight = 500;
        };
    }
}

public class WindowViewModel : INotifyPropertyChanged
{
    private InlaidViewModel _inlaidViewModel;
    public InlaidViewModel InlaidViewModel
    {
        get { return  _inlaidViewModel; }
        set {  _inlaidViewModel = value; NotifyPropertyChanged(); }
    }

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

}

public class InlaidViewModel : INotifyPropertyChanged
{
    private double _minHeight;
    public double MinHeight
    {
        get { return _minHeight; }
        set { _minHeight = value; NotifyPropertyChanged(); }
    }

    public event PropertyChangedEventHandler PropertyChanged;

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