使用 canavas 可以放大和缩小相机，而且我的 Windows Phone 应用程序的方向也有错误

Question

This is what i have tried so far for orientation and i am facing problem in potraitdown it shows image in up two thing that i want to do are First default camera orientation and Second Zoom in and Zoom out before capturing the image

I wrote this code in XAML

    <Canvas x:Name="viewfinderCanvas" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Margin="0,10">
        <Canvas.Background>
            <VideoBrush x:Name="viewfinderBrush">
                <VideoBrush.RelativeTransform>
                
                <CompositeTransform
                    x:Name="viewfinderTransform"
                    CenterX="0.5"
                    CenterY="0.5"
                    Rotation="-90" />
                    
                </VideoBrush.RelativeTransform>
            </VideoBrush>
        </Canvas.Background>
    </Canvas>

And this is for orientation C#

protected override  void OnOrientationChanged(OrientationChangedEventArgs e)
    {
     
        if (cam != null)
        {
     
            if (e.Orientation == PageOrientation.LandscapeRight)
            {
                landscapeRightRotation = 180;
                // Rotate for LandscapeRight orientation.
                viewfinderBrush.RelativeTransform =
                    new CompositeTransform() { CenterX = 0.5, CenterY = 0.5, Rotation = landscapeRightRotation };
            }
            else if (e.Orientation == PageOrientation.PortraitUp)
            {
                landscapeRightRotation = -90;
                viewfinderBrush.RelativeTransform =
                    new CompositeTransform() { CenterX = 0.5, CenterY = 0.5, Rotation = landscapeRightRotation };
            }
  
            else if (e.Orientation == PageOrientation.PortraitDown)
            {
                landscapeRightRotation = 0;
                // Rotate for LandscapeRight orientation.
                viewfinderBrush.RelativeTransform =
                    new CompositeTransform() { CenterX = 0.5, CenterY = 0.5, Rotation = landscapeRightRotation };
            }
            else
            {
                
                viewfinderBrush.RelativeTransform =
                    new CompositeTransform() { CenterX = 0.5, CenterY = 0.5, Rotation = 0 };
            }
        }
      
        viewfinderTransform.ScaleY = 0;
        base.OnOrientationChanged(e);
    }

Answer 1

I was able to solve the zoom in and zoom out by adding two things RenderTransform and Slider but still facing the problem in orientation Xaml updated

        <Canvas x:Name="viewfinderCanvas" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Margin="0,10">
        <Canvas.RenderTransform>
            <ScaleTransform x:Name="zoom"/>
            <!--<CompositeTransform scalex="-1"/>-->
        </Canvas.RenderTransform>
        <Canvas.Background>

            <VideoBrush x:Name="viewfinderBrush">
                <VideoBrush.RelativeTransform>

                    <CompositeTransform
                    x:Name="viewfinderTransform"
                    CenterX="0.5"
                    CenterY="0.5"
                    Rotation="-90" />

                </VideoBrush.RelativeTransform>
            </VideoBrush>
        </Canvas.Background>
    </Canvas>
    <Slider Foreground="White" Value="1" Opacity=".3" Background="White" Visibility="Visible" Name="zoomSlider" ValueChanged="zoomSlider_ValueChanged_1" Margin="0,570,0,10" />

And C# for zoomSlider_ValueChanged_1

  private void zoomSlider_ValueChanged_1(object sender, RoutedPropertyChangedEventArgs<double> e)
    {
        try
        {
            zoom.ScaleX = zoomSlider.Value;
            zoom.ScaleY = zoomSlider.Value;
            zoom.CenterX = 10;
            zoom.CenterY = 5;
        }
        catch (Exception)
        {
        }
    }