开发与分辨率无关的应用程序的技巧

Question

找到工作区测量值并在代码中设置一些属性以便将其绑定到 xaml 中 Control 的边距或高度/宽度属性是一个好习惯吗？

我这样做是为了让我的窗口根据可用的工作区域调整大小。

const int w = SystemParameters.WorkArea.Width;
const int h = SystemParameters.WorkArea.Height;

public Thickness OuterGridMargin { get; }

MainViewModel()
{
    OuterGridMargin = new Thickness(w/5,h/6,w/5,h/4);
}

xaml：

<Grid Margin="{Binding OuterGridMargin}" />

我对一些外部容器执行此操作，以便布局不会在较低分辨率下混乱。目前我在 20" 中以 1600x900 分辨率（96 dpi）工作。我的应用程序类似于小工具，没有常规窗口。

我想知道是否有一些替代方法。

搜索 [wpf] 分辨率]1 给出了很多解决类似问题的问题，但我仍然陷入困境，无法得出结论实现良好的与分辨率无关的布局。

Answer 1

WPF 中有两种处理分辨率的方法。

一种选择是设计为最小分辨率，并确保所有内容都适当停靠，以便元素随着窗口分辨率变大而变大。这就是很多人在 WinForms 中所做的事情，并且在 WPF 中仍然可以很好地工作。您可能已经对如何通过设置 Horizo​​ntalAlignment、VerticalAlignment 和边距来处理此问题有了一些概念。

在 WPF 中要做的更新、更时尚的事情在 WinForms 中几乎不可能做到，那就是让您的应用程序实际上只是放大，这样您的控件就会像窗口一样变大。为此，您将在窗口中的某些根元素上应用 ScaleTransform，并让 WPF 处理其余的事情。真的很酷。

为了展示它的样子，以下是启动应用程序时窗口的外观，将其变小，然后将其变大： https://i.sstatic.net/QeoVK.png

这是我制作的小型示例应用程序的隐藏代码：

public partial class MainWindow : Window
{
    public MainWindow() => InitializeComponent();

    #region ScaleValue Depdency Property
    public static readonly DependencyProperty ScaleValueProperty = DependencyProperty.Register("ScaleValue", typeof(double), typeof(MainWindow), new UIPropertyMetadata(1.0, new PropertyChangedCallback(OnScaleValueChanged), new CoerceValueCallback(OnCoerceScaleValue)));

    private static object OnCoerceScaleValue(DependencyObject o, object value)
    {
        MainWindow mainWindow = o as MainWindow;
        if (mainWindow != null)
            return mainWindow.OnCoerceScaleValue((double)value);
        else return value;
    }

    private static void OnScaleValueChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
    {
        MainWindow mainWindow = o as MainWindow;
        if (mainWindow != null)
            mainWindow.OnScaleValueChanged((double)e.OldValue, (double)e.NewValue);
    }

    protected virtual double OnCoerceScaleValue(double value)
    {
        if (double.IsNaN(value))
            return 1.0f;

        value = Math.Max(0.1, value);
        return value;
    }

    protected virtual void OnScaleValueChanged(double oldValue, double newValue) { }

    public double ScaleValue
    {            
        get => (double)GetValue(ScaleValueProperty);
        set => SetValue(ScaleValueProperty, value);
    }
    #endregion

    private void MainGrid_SizeChanged(object sender, EventArgs e) => CalculateScale();

    private void CalculateScale()
    {
        double yScale = ActualHeight / 250f;
        double xScale = ActualWidth / 200f;
        double value  = Math.Min(xScale, yScale);

        ScaleValue = (double)OnCoerceScaleValue(myMainWindow, value);
    }
}

以及 XAML：

<Window x:Class="WpfApplication1.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" 
    Name="myMainWindow"
    Width="200" Height="250">
<Grid Name="MainGrid" SizeChanged="MainGrid_SizeChanged">
    <Grid.LayoutTransform>
        <ScaleTransform x:Name="ApplicationScaleTransform"
                        CenterX="0"
                        CenterY="0"
                        ScaleX="{Binding ElementName=myMainWindow, Path=ScaleValue}"
                        ScaleY="{Binding ElementName=myMainWindow, Path=ScaleValue}" />
    </Grid.LayoutTransform>
    <Grid VerticalAlignment="Center" HorizontalAlignment="Center" Height="150">
        <TextBlock FontSize="20" Text="Hello World" Margin="5" VerticalAlignment="Top" HorizontalAlignment="Center"/>
        <Button Content="Button" VerticalAlignment="Bottom" HorizontalAlignment="Center"/>
    </Grid>
</Grid>

Answer 2

JacobJ 的回答很好，我尝试了一下，效果非常好。

对于任何感兴趣的人，我做了一个附加行为，它做了同样的事情。我还添加了从 XAML 指定宽度/高度分母的选项。可以这样使用

<Grid Name="MainGrid"
      inf:ScaleToWindowSizeBehavior.Denominators="1000, 700"
      inf:ScaleToWindowSizeBehavior.ParentWindow="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}}}">
    <!--...-->
</Grid>

ScaleToWindowSizeBehavior

public static class ScaleToWindowSizeBehavior
{
    #region ParentWindow

    public static readonly DependencyProperty ParentWindowProperty =
        DependencyProperty.RegisterAttached("ParentWindow",
                                             typeof(Window),
                                             typeof(ScaleToWindowSizeBehavior),
                                             new FrameworkPropertyMetadata(null, OnParentWindowChanged));

    public static void SetParentWindow(FrameworkElement element, Window value)
    {
        element.SetValue(ParentWindowProperty, value);
    }

    public static Window GetParentWindow(FrameworkElement element)
    {
        return (Window)element.GetValue(ParentWindowProperty);
    }

    private static void OnParentWindowChanged(DependencyObject target,
                                              DependencyPropertyChangedEventArgs e)
    {
        FrameworkElement mainElement = target as FrameworkElement;
        Window window = e.NewValue as Window;

        ScaleTransform scaleTransform = new ScaleTransform();
        scaleTransform.CenterX = 0;
        scaleTransform.CenterY= 0;
        Binding scaleValueBinding = new Binding
        {
            Source = window,
            Path = new PropertyPath(ScaleValueProperty)
        };
        BindingOperations.SetBinding(scaleTransform, ScaleTransform.ScaleXProperty, scaleValueBinding);
        BindingOperations.SetBinding(scaleTransform, ScaleTransform.ScaleYProperty, scaleValueBinding);
        mainElement.LayoutTransform = scaleTransform;
        mainElement.SizeChanged += mainElement_SizeChanged;
    }

    #endregion // ParentWindow

    #region ScaleValue

    public static readonly DependencyProperty ScaleValueProperty =
        DependencyProperty.RegisterAttached("ScaleValue",
                                            typeof(double),
                                            typeof(ScaleToWindowSizeBehavior),
                                            new UIPropertyMetadata(1.0, OnScaleValueChanged, OnCoerceScaleValue));

    public static double GetScaleValue(DependencyObject target)
    {
        return (double)target.GetValue(ScaleValueProperty);
    }
    public static void SetScaleValue(DependencyObject target, double value)
    {
        target.SetValue(ScaleValueProperty, value);
    }

    private static void OnScaleValueChanged(DependencyObject target, DependencyPropertyChangedEventArgs e)
    {
    }

    private static object OnCoerceScaleValue(DependencyObject d, object baseValue)
    {
        if (baseValue is double)
        {
            double value = (double)baseValue;
            if (double.IsNaN(value))
            {
                return 1.0f;
            }
            value = Math.Max(0.1, value);
            return value;
        }
        return 1.0f;
    }

    private static void mainElement_SizeChanged(object sender, SizeChangedEventArgs e)
    {
        FrameworkElement mainElement = sender as FrameworkElement;
        Window window = GetParentWindow(mainElement);
        CalculateScale(window);
    }

    private static void CalculateScale(Window window)
    {
        Size denominators = GetDenominators(window);
        double xScale = window.ActualWidth / denominators.Width;
        double yScale = window.ActualHeight / denominators.Height;
        double value = Math.Min(xScale, yScale);
        SetScaleValue(window, value);
    }

    #endregion // ScaleValue

    #region Denominators

    public static readonly DependencyProperty DenominatorsProperty =
        DependencyProperty.RegisterAttached("Denominators",
                                            typeof(Size),
                                            typeof(ScaleToWindowSizeBehavior),
                                            new UIPropertyMetadata(new Size(1000.0, 700.0)));

    public static Size GetDenominators(DependencyObject target)
    {
        return (Size)target.GetValue(DenominatorsProperty);
    }
    public static void SetDenominators(DependencyObject target, Size value)
    {
        target.SetValue(DenominatorsProperty, value);
    }

    #endregion // Denominators
}

Answer 3

对 Fredrik Hedblad 的答案进行小修正：

因为您已在 Grid 元素中设置 DependencyProperty“分母”：

<Grid Name="MainGrid"
      inf:ScaleToWindowSizeBehavior.Denominators="1000, 700"
    <!--...-->
</Grid>

您必须使用网格调用 GetDominator 方法。
而不是：

private static void CalculateScale(Window window)
{
    var denominators = GetDenominators(window);
}

你必须使用这样的东西：

private static void mainElement_SizeChanged(object sender, SizeChangedEventArgs e)
{
    var mainElement = sender as FrameworkElement;
    var window = GetParentWindow(mainElement);

    CalculateScale(window, mainElement);
}

private static void CalculateScale(Window window, FrameworkElement mainElement)
{
    var denominators = GetDenominators(mainElement);
}

Answer 4

按照 JacobJ 先生的做法，我制作了自己的衍生作品。
我创建了一个接口，我们在此基础上进行了更改

public interface IResolutionDecorator
{
    double ActualWidth { get; }
    double ActualHeight { get; }
    double ResolutionHeight { get; set; }
    double ResolutionWidth { get; set; }
    object CurentContent { get; }
}

，对于这个接口，我

    #region IResolutionDecorator
    private static double OnCoerceScaleValue(double value)
    {
        return double.IsNaN(value) ? 1d : Math.Max(0.1, value);
    }

    public static void UpdateScale(this IResolutionDecorator source)
    {
        if (source.CurentContent is Visual visual)
        {
            double yScale = source.ActualHeight / source.ResolutionHeight;
            double xScale = source.ActualWidth / source.ResolutionWidth;
            double value = Math.Min(xScale, yScale);
            double ScaleValue = (double)OnCoerceScaleValue(value);
            visual.SetValue(Grid.LayoutTransformProperty, new ScaleTransform(ScaleValue, ScaleValue, 0, 0));
        }
    }
    #endregion

现在有了扩展，我们只需要添加主窗口中缺少的参数，并在主网格中的事件 sizeChanged 中设置 this.UpdateScale()

public partial class MainWindow : Window,  IResolutionDecorator
{
    public MainWindow()
    {
        InitializeComponent();
        this.Height = ResolutionHeight;
        this.Width = ResolutionWidth;
    }
    #region IResolutionDecorator
    public object CurentContent { get{ return this.Content; } }
    public double ResolutionHeight { get; set; } = 400d;
    public double ResolutionWidth { get; set; } = 800d;
    #endregion

    private void MainGrid_SizeChanged(object sender, EventArgs e)
    {
        this.UpdateScale();
    }
}