我正在将一个WPF Visual(UserControl)呈现为位图,但问题在于呈现的图像是缩放/变换之前的UserControl大小。因此,假设UserControl设计为200x200像素。当我渲染到BMP时,我使用的是UserControl的ActualWidth和ActualHeightt,它们分别报告为200和200。问题在于UserControl位于Canvas中,并且自动调整大小(设置为随窗口大小缩放/填充)以接近1200 x 1200(它会改变)
我已经阅读并搜索了一些内容,到目前为止还无法确定有效大小,即控件在屏幕上被绘制的大小。
我遇到了这个问题,听起来很有希望,但返回的Transform不包含缩放数据。嗯,它确实包含,但它们都是1。 Get element position after transform 有什么建议可以查找渲染缩放比例的地方!
[更新]如建议所示,我包括了相关代码:
我已经阅读并搜索了一些内容,到目前为止还无法确定有效大小,即控件在屏幕上被绘制的大小。
我遇到了这个问题,听起来很有希望,但返回的Transform不包含缩放数据。嗯,它确实包含,但它们都是1。 Get element position after transform 有什么建议可以查找渲染缩放比例的地方!
[更新]如建议所示,我包括了相关代码:
public static Bitmap PngBitmap(this Visual visual)
{
// Get height and width
int width = (int)(double)visual.GetValue(
FrameworkElement.ActualWidthProperty);
int height = (int)(double)visual.GetValue(
FrameworkElement.ActualHeightProperty);
// Render
RenderTargetBitmap rtb =
new RenderTargetBitmap(
width,
height,
96,
96,
PixelFormats.Default);
rtb.Render(visual);
// Encode
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(rtb));
System.IO.MemoryStream stream = new System.IO.MemoryStream();
encoder.Save(stream);
// Create Bitmap
Bitmap bmp = new Bitmap(stream);
stream.Close();
return bmp;
}
public static BitmapSource BitmapSource(this Visual visual)
{
Bitmap bmp = visual.PngBitmap();
IntPtr hBitmap = bmp.GetHbitmap();
BitmapSizeOptions sizeOptions = BitmapSizeOptions.FromEmptyOptions();
return Imaging.CreateBitmapSourceFromHBitmap(
hBitmap,
IntPtr.Zero,
Int32Rect.Empty,
sizeOptions);
}
[更新 #2] 添加了 XAML - Grid 元素被移除,因为它太大了,根据我阅读的 XAML,包含键盘 UserControl 的 Canvas 不是 Grid 元素的一部分。<UserControl xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:PMD.HECAT.DashboardModule"
xmlns:PMD_HECAT_DashboardModule_VirtualKeyboard="clr-namespace:PMD.HECAT.DashboardModule.VirtualKeyboard"
xmlns:System_Windows_Controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Input.Toolkit"
xmlns:PMD_HECAT_DashboardModule_Input="clr-namespace:PMD.HECAT.DashboardModule.Input"
xmlns:control="clr-namespace:PMD.HECAT.DashboardModule.Controls"
x:Class="PMD.HECAT.DashboardModule.CandidateElectrodeView"
x:Name="UserControl"
mc:Ignorable="d"
d:DesignWidth="1024" d:DesignHeight="768" Width="640" Height="360">
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="../Themes/DashboardStyles.xaml" />
<ResourceDictionary Source="../Themes/ImageButtons.xaml" />
<ResourceDictionary Source="CandidateViewResources.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</UserControl.Resources>
<UserControl.Triggers>
<EventTrigger RoutedEvent="PMD_HECAT_DashboardModule_VirtualKeyboard:VirtualKeyboardView.KeyboardClose" SourceName="virtualKeyboardView">
<BeginStoryboard Storyboard="{StaticResource OnKeyboardClose1}"/>
</EventTrigger>
</UserControl.Triggers>
<Canvas Width="100" HorizontalAlignment="Left">
<PMD_HECAT_DashboardModule_VirtualKeyboard:VirtualKeyboardView x:Name="virtualKeyboardView" Height="222" Width="550" RenderTransformOrigin="0.5,0.5" Opacity="0" Active="False">
<PMD_HECAT_DashboardModule_VirtualKeyboard:VirtualKeyboardView.RenderTransform>
<TransformGroup>
<ScaleTransform/>
<SkewTransform/>
<RotateTransform/>
<TranslateTransform X="40" Y="400"/>
</TransformGroup>
</PMD_HECAT_DashboardModule_VirtualKeyboard:VirtualKeyboardView.RenderTransform>
</PMD_HECAT_DashboardModule_VirtualKeyboard:VirtualKeyboardView>
<Rectangle Stroke="White" Opacity="0.7" Fill="White" Height="370" Width="654.851" Canvas.Left="687" Canvas.Top="0" />
</Canvas>
</UserControl>