Capture Element not using room from parent control - xaml

Question

I am trying to create a page with a capture element and a button overlaid on top to take the picture.
The problem I've got is, the capture element won't use up the whole screen. There are bars above and below.
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="100"/>
</Grid.RowDefinitions>
<CaptureElement
Grid.Row="0"
x:Name="capPreview"
Stretch="Uniform"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Tapped="capPreview_Tapped"
/>
<Button Content="Submit"
HorizontalAlignment="Center"
Grid.Row="1"
x:Name="btnTakePicture"
Click="btnTakePicture_Click">
<Button.Background>
<SolidColorBrush Color="Black" Opacity="100"/>
</Button.Background>
<Button.BorderBrush>
<SolidColorBrush Color="White"/>
</Button.BorderBrush>
</Button>
</Grid>
Edit: I have since used the code behind to rotate the capture element, however; upon doing so, the element now just has a box all around it instead of top and bottom.
<CaptureElement
Grid.Row="0"
x:Name="capPreview"
Tapped="capPreview_Tapped"
/>
Short of hard coding the height and width values, I am out of ideas.

Answer 1

It deos use the whole screen, the issue is the orientation of the preview is different than the orientation of the screen.
MediaCapture has a method SetPreviewRotation to handle this issue.

Answer 2

It works for me :) Just grid and Strech, If you want to have focus just make transparent grid outside CaptureElement
<Grid>
<Grid Tapped="SetFocus">
<CaptureElement x:Name="CaptureElement" Stretch="UniformToFill"/>
</Grid>
<Grid VerticalAlignment="Bottom">
<Button x:Name="SaveButton" Foreground="Transparent" IsDoubleTapEnabled="False" Width="48" Height="48" Background="Transparent" BorderBrush="Transparent"
Click="OnSaveButtonClicked" HorizontalAlignment="Stretch" Margin="12,0">
</Button>
</Grid>
</Grid>

Answer 3

Try this one it will capture directly with the button click
private async void Button_Click_3(object sender, RoutedEventArgs e)
{
Uri u = new Uri("ms-data:///local");
StorageFile file = await ApplicationData.Current.LocalFolder.GetFileAsync("Photo.jpg");
IRandomAccessStream st = await file.OpenAsync(FileAccessMode.Read);
BitmapImage image = new BitmapImage();
image.SetSource(st);
img.Source = image;
}
<CaptureElement Name="element" Height="600"/>
<StackPanel>
<Button Content="Capture Image" Click="Button_Click_3"/>
</StackPanel>
<Image Name="img" Margin="0,0,0,0"/>