How to disable cache in Windows 8 Xaml based ListView? - c++

Question

What I'm trying to do is to fill ListView in Windows 8 Metro application dynamically with pre-loaded images.
for each item (URI) I'm doing it plain simple with the code like this (C++):
Windows::UI::Xaml::Media::Imaging::BitmapImage^ bitmapSrc =
ref new Windows::UI::Xaml::Media::Imaging::BitmapImage();
bitmapSrc->CreateOptions = Windows::UI::Xaml::Media::Imaging::BitmapCreateOptions::IgnoreImageCache;
bitmapSrc->UriSource = uri;
img->Source = bitmapSrc;
LoadListView->Items->Append(img);
but when I delete (in the app) source image described by URI and I create new file with the same name and try to reload it into the list then I fail and image shown is the old one (deleted). I presume some cache works here. I tried to avoid caching by IgnoreImageCache value in CreateOptions but it didn't work.
Any clues how to disable caching of BitmapSource (Image) potentially bound to ListView in Windows 8 app?
I tried several directions inspired by Silverlight and WPF, none worked unfortunately.

Answer 1

Encouraged by comments, I put answer I've found myself.
Broader context (and also C# perspective) is explained here:
http://social.msdn.microsoft.com/Forums/en-US/winappswithcsharp/thread/171dfe66-78b5-4340-bd78-244337f31287/
Shortly I believe it's a problem with reference counting here.
WinRT keeps the image loaded (cached) in BitmapImage^ as long as Uri is valid and asigned to the object instance, that in my example is added to the list.
Cleaning Uri from BitmapImage^ prior to releasing it from the list solved problem in my case.
According to example in question, below code solves the problem (included in the part where the list removal is performed):
auto item = (Image^)LoadListView->Items->GetAt(selected);
auto src = (Windows::UI::Xaml::Media::Imaging::BitmapImage^)item->Source;
src->UriSource = nullptr; //this line is critical
LoadListView->Items->RemoveAt(selected);