To use writeable bitmap I need to wait until an image is loaded .
I am having all sorts of problems detecting if an image is loaded as when I load dynamic images from a class .
Is there another way I can detect if an image is loaded.
uu = New BitmapImage(url)
uu.UriSource = url
img.Source = uu
Canvas.SetLeft(img, _x)
Canvas.SetTop(img, _y)
'img.SetValue(Canvas.ZInde
Canvas.SetZIndex(img, 10)
canvas1.Children.Add(img)
AddHandler uu.DownloadProgress, AddressOf uu_downloadProgress
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Ok if that is the case, then your code needs to change
uu = New BitmapImage(url)
uu.UriSource = url
To: (C# code sample)
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.DownloadProgre
new EventHandler<DOWNLOADPROGRE
bitmapImage.DownloadComple
new EventHandler(bitmapImage_D
bitmapImage.UriSource = new Uri(URL, UriKind.Absolute);
You also need to implement DownloadCompleted and assign your image there.
{ //All your image code here
Canvas.SetLeft(img, _x)
Canvas.SetTop(img, _y)
'img.SetValue(Canvas.ZInde
Canvas.SetZIndex(img, 10)
canvas1.Children.Add(img)
}
Note: DownloadProgress is only to show download progress of the bitmap content. You cannot assign images there.
Thanks for the reply as I am really frustrated with this.
i was told you check the e.Progress value for the download progress.
SO this is not correct ?
Public Sub uu_downloadProgress(ByVal sender As Object, ByVal e As DownloadProgressEventArgs)
Dim i As Integer
Dim c As Color
Dim myuu As BitmapImage
myuu = sender
If e.Progress = 100 Then
img.Height = img.ActualHeight
img.Width = img.ActualWidth
wb = New WriteableBitmap(myuu)
This code is not correct because your "if" logic only covers one line. (img.Height = img.ActualHeight)
if you want to use this construct, just change:
If e.Progress = 100 Then
img.Height = img.ActualHeight
img.Width = img.ActualWidth
wb = New WriteableBitmap(myuu)
End If
Notice the end if that ensures your code only writes when the progress is 100% (At the moment is writing even if it is say 50%). Again it is your choice but I prefer DownloadCompleted event.
yes i do use this below as written and it doesnt work all the time.
half the time the image never loads and i am wondering why this is.
I will try your code later and hope that goes ok as my code isnt doing the trick.
If e.Progress = 100 Then
img.Height = img.ActualHeight
img.Width = img.ActualWidth
wb = New WriteableBitmap(myuu)
End If
http://blogs.silverlight.n
The call to Dispatcher.BeginInvoke(del
is this the problem as i am getting occasional 0 values and that is why the image sometimes load? I cant trnaslate this into vb.net though
it is defined in BitmapImage bae class BitmapSource.From msdn:
"Occurs when the bitmap content has been completely downloaded.
Namespace: System.Windows.Media.Imagi
Assembly: PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.c
Syntax
Visual Basic (Declaration)
Public Overridable Event DownloadCompleted As EventHandler
Visual Basic (Usage)
Dim instance As BitmapSource
Dim handler As EventHandler
AddHandler instance.DownloadCompleted
"
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by: mas_oz2003Posted on 2009-11-01 at 14:18:12ID: 25715859
Is this image coming from your local hard drive or the internet?
If local or network share, you can load it to a FileStream with exclusive access.
lStream = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None);