Question

我正在开发一个WPF应用程序，它将以全高清LCD屏幕（42英寸）显示。另外，我需要在绝对位置容纳控件。在开发环境中，我看不到长度为1920x1080的窗口（这是目标屏幕的固定分辨率）。

完成此任务的最佳做法是什么？

Answer 1

WPF使用设备无关单元指定宽度/高度/位置/厚度等

当屏幕DPI设置为96dpi时，

1 DIU / DIP = 1个物理像素.......当DPI不是96dpi时，1 DIU =不同数量的物理像素。

如果使用Canvas，则使用DIU定位元素。

现在你暗示你想要在像素坐标方面绝对定位。

所以要使用Canvas执行此操作，无论当前的DPI设置是什么，您都必须使用缩放技巧（可以使用ViewBox或LayoutTransform执行此操作）。

以下示例显示了实现它的一种方法（我的屏幕是1366x768 ....您可以将其更改为全高清）。

它会查看系统的DPI，并在DPI上升时缩小Canvas。这允许您使用真正意味着像素坐标的Canvas坐标。

如果您能够将用户屏幕更改为96dpi，则无需进行缩放技巧，因为1 DIU = 96dpi时的1个物理像素...无需重新缩放。

<Window x:Class="WpfApplication12.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        WindowStyle="None"
        AllowsTransparency="True" Background="White"
        SizeToContent="WidthAndHeight"
        Title="MainWindow" Loaded="Window_Loaded">
    <Viewbox x:Name="viewbox">
    <Canvas x:Name="canvas">
        <Rectangle x:Name="rect" Canvas.Top="10" Canvas.Left="10" Stroke="Red" StrokeThickness="1"/>
        <Button Canvas.Top="20" Canvas.Left="20">Test Button</Button>
            <Ellipse Canvas.Top="100" Canvas.Left="100" Width="100" Height="100" Stroke="Red" StrokeThickness="10"/>
            <TextBlock Canvas.Top="100" Canvas.Left="100" FontSize="15">Some Text</TextBlock>
        </Canvas>
    </Viewbox>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApplication12
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        // HD
        const int screenwidth = 1366;
        const int screenheight = 768;

        // FULL HD
        //const int screenwidth = 1920;
        //const int screenheight = 1080;

        public MainWindow()
        {
            InitializeComponent();

            Top = 0;
            Left = 0;

            canvas.Width = screenwidth;
            canvas.Height = screenheight;

            rect.Width = screenwidth - 20;
            rect.Height = screenheight - 20;
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            bool bScaleBackToPixels = true;

            if (bScaleBackToPixels)
            {
                PresentationSource presentationsource = PresentationSource.FromVisual(this);
                Matrix m = presentationsource.CompositionTarget.TransformToDevice;

                double DpiWidthFactor = m.M11;
                double DpiHeightFactor = m.M22;

                viewbox.Width = screenwidth / DpiWidthFactor;
                viewbox.Height = screenheight / DpiHeightFactor;
            }
            else
            {
                viewbox.Width = screenwidth;
                viewbox.Height = screenheight;
            }
        }
    }
}

<Window x:Class="WpfApplication12.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        WindowStyle="None"
        AllowsTransparency="True" Background="White"
        SizeToContent="WidthAndHeight"
        Title="MainWindow" Loaded="Window_Loaded">
    <Canvas x:Name="canvas">
        <Rectangle x:Name="rect" Canvas.Top="10" Canvas.Left="10" Stroke="Red" StrokeThickness="1"/>
        <Button Canvas.Top="20" Canvas.Left="20">Test Button</Button>
            <Ellipse Canvas.Top="100" Canvas.Left="100" Width="100" Height="100" Stroke="Red" StrokeThickness="10"/>
            <TextBlock Canvas.Top="100" Canvas.Left="100" FontSize="15">Some Text</TextBlock>
        </Canvas>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApplication12
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        // HD
        const int screenwidth = 1366;
        const int screenheight = 768;

        // FULL HD
        //const int screenwidth = 1920;
        //const int screenheight = 1080;

        public MainWindow()
        {
            InitializeComponent();

            Top = 0;
            Left = 0;

            canvas.Width = screenwidth;
            canvas.Height = screenheight;

            rect.Width = screenwidth - 20;
            rect.Height = screenheight - 20;
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            bool bScaleBackToPixels = true;

            if (bScaleBackToPixels)
            {
                PresentationSource presentationsource = PresentationSource.FromVisual(this);
                Matrix m = presentationsource.CompositionTarget.TransformToDevice;

                double DpiWidthFactor = m.M11;
                double DpiHeightFactor = m.M22;

                double scalex = 1 / DpiWidthFactor;
                double scaley = 1 / DpiHeightFactor;

                canvas.LayoutTransform = new ScaleTransform(scalex, scaley);
            }
        }
    }
}

在96 DPI设置（较小 - 100％）时，屏幕如下所示：

enter image description here

在120 DPI设置（中等 - 125％）（即96 x 1.25 = 120DPI）时，当使用上面的ScaleBackToPixels技术时屏幕看起来像这样（即它看起来与第一个屏幕相同）。

enter image description here

在120 DPI设置（中等 - 125％）（即96 x 1.25 = 120DPI）时，如果您根本不做任何调整，屏幕看起来像这样（请注意圆圈的大小，字体和大小按钮）。

enter image description here

所有3张图片并排进行比较：

enter image description here

Answer 2

以下是使我的笔记本电脑屏幕分辨率为1366x768的屏幕分辨率为1920x1080（全高清）的转换：

<强> XAML

        <ContentControl  Canvas.Left="1630" Canvas.Top="400" Content="{Binding Time}" />
        <ContentControl  Canvas.Left="1630" Canvas.Top="590" Content="{Binding NextPrayTime}" />
        <ContentControl  Canvas.Left="1650" Canvas.Top="700" Content="{Binding Today}" />
        <ContentControl  Canvas.Right="520" Canvas.Top="120" Content="{Binding Content}" />
        <ContentControl  Canvas.Left="0" Canvas.Top="965" Content="{Binding PrayTimes}">

        </ContentControl>
    </Canvas>
</Viewbox>

<强> C＃

static public class HD
{
    static public float Width { get { return 1366.0f; } }
    static public float Height { get { return 768.0f; } }
}

static public class FHD
{
    static public float Width { get { return 1920.0f; } }
    static public float Height { get { return 1080.0f; } }
}

static public class HDRatios
{
    static public double Width
    {
        get
        {
#if (DEBUG)
            return double.Parse((HD.Width / FHD.Width).ToString("0.0"));
#else
            return 1;
#endif
        }
    }
    static public double Height
    {
        get
        {
#if (DEBUG)
            return double.Parse((HD.Height / FHD.Height).ToString("0.0"));
#else
            return 1;
#endif
        }
    }

该代码演示了在开发环境（DEBUG标志）中将应用转换，并且在发布版本中将不会应用转换，因为Canvas.Left和Canvas.Top是根据Full的分辨率HD。

我希望这种体验能够帮助那些在绝对指标Canvas内在WPF中显示控件的人。

WPF用于液晶屏全高清

2 个答案: