WPF用于液晶屏全高清

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使用设备无关单元来指定宽度/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.

如果你使用它Canvas然后使用DIU定位元素.

现在你暗示你想要在像素坐标方面绝对定位.

所以要做到这一点,Canvas无论当前的DPI设置是什么,你都必须使用缩放技巧(你可以使用a ViewBox或a LayoutTransform).

下面的例子显示了实现它的一种方法(我的屏幕是1366x768 ....你可以将它改为全高清).

它会查看系统的DPI,并Canvas在DPI上升时按比例缩小.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,则无需执行缩放技巧,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:

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

在120 DPI设置(中等 - 125%)(即96 x 1.25 = 120DPI)时,如果您根本不进行任何调整,屏幕看起来像这样(请注意圆圈的大小以及按钮的字体和大小).

所有3张图片并排进行比较: