async Task <Stream> GetStreamAsync(Uri uri, CancellationToken cancellationToken = default(CancellationToken))
{
cancellationToken.ThrowIfCancellationRequested();
Stream stream = null;
if (CachingEnabled)
{
stream = await GetStreamFromCacheAsync(uri, cancellationToken).ConfigureAwait(false);
}
if (stream == null)
{
try
{
stream = await Device.GetStreamAsync(uri, cancellationToken).ConfigureAwait(false);
}
catch (Exception ex)
{
Xamarin.Forms.Internals.Log.Warning("Image Loading", $"Error getting stream for {Uri}: {ex}");
stream = null;
}
}
return(stream);
}
async Task <Stream> GetStreamAsyncUnchecked(string key, Uri uri, CancellationToken cancellationToken)
{
if (await GetHasLocallyCachedCopyAsync(key).ConfigureAwait(false))
{
var retry = 5;
while (retry >= 0)
{
int backoff;
try
{
Stream result = await Store.OpenFileAsync(Path.Combine(CacheName, key), FileMode.Open, FileAccess.Read).ConfigureAwait(false);
return(result);
}
catch (IOException)
{
// iOS seems to not like 2 readers opening the file at the exact same time, back off for random amount of time
backoff = new Random().Next(1, 5);
retry--;
}
if (backoff > 0)
{
await Task.Delay(backoff);
}
}
return(null);
}
Stream stream;
try
{
stream = await Device.GetStreamAsync(uri, cancellationToken).ConfigureAwait(false);
if (stream == null)
{
return(null);
}
}
catch (Exception ex)
{
Log.Warning("Image Loading", $"Error getting stream for {Uri}: {ex}");
return(null);
}
Stream writeStream = await Store.OpenFileAsync(Path.Combine(CacheName, key), FileMode.Create, FileAccess.Write).ConfigureAwait(false);
await stream.CopyToAsync(writeStream, 16384, cancellationToken).ConfigureAwait(false);
if (writeStream != null)
{
writeStream.Dispose();
}
stream.Dispose();
return(await Store.OpenFileAsync(Path.Combine(CacheName, key), FileMode.Open, FileAccess.Read).ConfigureAwait(false));
}
async Task <Stream> GetStreamAsync(Uri uri, CancellationToken cancellationToken = default(CancellationToken))
{
cancellationToken.ThrowIfCancellationRequested();
Stream stream;
if (!CachingEnabled)
{
try
{
stream = await Device.GetStreamAsync(uri, cancellationToken).ConfigureAwait(false);
}
catch (Exception)
{
stream = null;
}
}
else
{
stream = await GetStreamFromCacheAsync(uri, cancellationToken).ConfigureAwait(false);
}
return(stream);
}
