Generating a secondary tile with image not showing image immediately

Question

When adding a newly generated image to a secondary tile, it doesn't find it initially - why and how do I fix it?

The full story

Hello, I'm working on a Windows Phone application that creates secondary live tiles on the phone's home screen.

Since there is currently no easy way to generate a secondary live tile with given XAML I do the following:

• Create a UserControl with given XAML and data bind it to my data
• Use WriteableBitmap to write it after data binding to an image.
• Use PNGWriter to write it to isolated storage
• Create the live tile with the generated isostore:/ url.

This kinda works, the problem is when the tile is created it's not showing, only after time passes the tile suddenly appears correctly.

I use the following code for generation:

public static void GenerateMediumTile(DashboardViewModel source)
{
    var image = new LiveTileMedium() {DataContext = source};
    image.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));
    image.Arrange(new Rect(0,0,336,336));
    var  bitmap = new WriteableBitmap(336,336);
    bitmap.Render(image,new TranslateTransform());
    bitmap.Invalidate();
    using (var fileStore = IsolatedStorageFile.GetUserStoreForApplication())
    {
        var file = fileStore.OpenFile("Shared/ShellContent/tile_" + source.Ticker + "_medium.png", FileMode.Create);
        bitmap.WritePNG(file.AsOutputStream().AsStreamForWrite());
    }   
}

Then this code for creating the tile:

var largeImageFile = isostoreSharedShellcontentTile + tileImage.Ticker + "_big.png";

var oFliptile = new FlipTileData
{
    Title = "",
    BackTitle = "",
    BackContent = "",
    SmallBackgroundImage = new Uri("/Assets/Matrial/small_tile159x159.png", UriKind.RelativeOrAbsolute),
    BackgroundImage = new Uri(mediumImageFile, UriKind.Absolute),
    ...

ShellTile.Create(new Uri(url, UriKind.Relative), oFliptile, true);

Here is what the tile looks like when I'm creating it, and then after time passes and I enter another app.

Answer 1

It’s just a guess, but maybe disposing fileStore doesn’t dispose file — it will happen once garbage collection occurs, but until then, the file can’t be read. So:

using (var fileStore = IsolatedStorageFile.GetUserStoreForApplication())
{
    using (var file = fileStore.OpenFile("Shared/ShellContent/tile_" + source.Ticker + "_medium.png", FileMode.Create))
    {
        bitmap.WritePNG(file.AsOutputStream().AsStreamForWrite());
    }
}