Drawing a WPF UserControl with DataBinding to an Image
- by LorenVS
Hey Everyone,
So I'm trying to use a WPF User Control to generate a ton of images from a dataset where each item in the dataset would produce an image...
I'm hoping I can set it up in such a way that I can use WPF databinding, and for each item in the dataset, create an instance of my user control, set the dependency property that corresponds to my data item, and then draw the user control to an image, but I'm having problems getting it all working (not sure whether databinding or drawing to the image is my problem)
Sorry for the massive code dump, but I've been trying to get this working for a couple of hours now, and WPF just doesn't like me (have to learn at some point though...)
My User Control looks like this:
<UserControl x:Class="Bleargh.ImageTemplate"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:c="clr-namespace:Bleargh"
x:Name="ImageTemplateContainer"
Height="300" Width="300">
<Canvas>
<TextBlock Canvas.Left="50" Canvas.Top="50" Width="200" Height="25" FontSize="16" FontFamily="Calibri" Text="{Binding Path=Booking.Customer,ElementName=ImageTemplateContainer}" />
<TextBlock Canvas.Left="50" Canvas.Top="100" Width="200" Height="25" FontSize="16" FontFamily="Calibri" Text="{Binding Path=Booking.Location,ElementName=ImageTemplateContainer}" />
<TextBlock Canvas.Left="50" Canvas.Top="150" Width="200" Height="25" FontSize="16" FontFamily="Calibri" Text="{Binding Path=Booking.ItemNumber,ElementName=ImageTemplateContainer}" />
<TextBlock Canvas.Left="50" Canvas.Top="200" Width="200" Height="25" FontSize="16" FontFamily="Calibri" Text="{Binding Path=Booking.Description,ElementName=ImageTemplateContainer}" />
</Canvas>
</UserControl>
And I've added a dependency property of type "Booking" to my user control that I'm hoping will be the source for the databound values:
public partial class ImageTemplate : UserControl
{
public static readonly DependencyProperty BookingProperty = DependencyProperty.Register("Booking", typeof(Booking), typeof(ImageTemplate));
public Booking Booking
{
get { return (Booking)GetValue(BookingProperty); }
set { SetValue(BookingProperty, value); }
}
public ImageTemplate()
{
InitializeComponent();
}
}
And I'm using the following code to render the control:
List<Booking> bookings = Booking.GetSome();
for(int i = 0; i < bookings.Count; i++)
{
ImageTemplate template = new ImageTemplate();
template.Booking = bookings[i];
RenderTargetBitmap bitmap = new RenderTargetBitmap(
(int)template.Width,
(int)template.Height,
120.0,
120.0,
PixelFormats.Pbgra32);
bitmap.Render(template);
BitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bitmap));
using (Stream s = File.OpenWrite(@"C:\Code\Bleargh\RawImages\" + i.ToString() + ".png"))
{
encoder.Save(s);
}
}
EDIT:
I should add that the process works without any errors whatsoever, but I end up with a directory full of plain-white images, not text or anything... And I have confirmed using the debugger that my Booking objects are being filled with the proper data...
EDIT 2:
Did something I should have done a long time ago, set a background on my canvas, but that didn't change the output image at all, so my problem is most definitely somehow to do with my drawing code (although there may be something wrong with my databinding too)
