protected override Size MeasureOverride(Size availableSize)
{
var progress = this.Progress;
if (progress != null)
{
if (!Double.IsInfinity(availableSize.Width))
{
progress.Width = Math.Min(96, Math.Max(8, availableSize.Width * 0.5));
}
if (!Double.IsInfinity(availableSize.Height))
{
progress.Height = Math.Min(96, Math.Max(8, availableSize.Height * 0.5));
}
base.MeasureOverride(availableSize);
_currentSize = NormalizeSize(availableSize);
return(_currentSize);
}
var newSize = new Size(Math.Min(Int16.MaxValue, availableSize.Width), Math.Min(Int16.MaxValue, availableSize.Height));
if (_isHttpSource && BitmapCache.GetSizeLevel(_currentSize) != BitmapCache.GetSizeLevel(newSize))
{
_currentSize = newSize;
RefreshSourceUri(_currentUri);
}
return(base.MeasureOverride(availableSize));
}
private async void SetSourceUri(Uri uri)
{
_currentUri = uri;
if (uri.IsAbsoluteUri)
{
var cachedUri = uri;
if (uri.Scheme == "http" || uri.Scheme == "https")
{
SetProgress();
_isHttpSource = true;
if (!Windows.ApplicationModel.DesignMode.DesignModeEnabled)
{
cachedUri = await BitmapCache.GetImageUriAsync(uri, (int)_currentSize.Width, (int)_currentSize.Height);
}
}
if (Path.GetExtension(uri.LocalPath).Equals(".gif", StringComparison.OrdinalIgnoreCase))
{
this.SetImageGif(cachedUri);
}
else
{
this.SetImage(new BitmapImage(cachedUri));
}
}
else
{
ClearImage();
ClearImageGif();
}
}
private async void RefreshSourceUri(Uri uri)
{
if (!Windows.ApplicationModel.DesignMode.DesignModeEnabled)
{
uri = await BitmapCache.GetImageUriAsync(uri, (int)_currentSize.Width, (int)_currentSize.Height);
}
this.SetImage(new BitmapImage(uri));
}
public static async Task <bool> DownloadImageAsync(StorageFile file, Uri uri, int maxWidth = Int32.MaxValue, int maxHeight = Int32.MaxValue)
{
StorageFile tempFile = null;
try
{
using (var httpClient = new HttpClient())
{
using (var httpMessage = await httpClient.GetAsync(uri))
{
var cacheFolder = await BitmapCache.EnsureCacheFolderAsync();
tempFile = await cacheFolder.CreateFileAsync($"{file.Name}.tmp");
using (var fileStream = await tempFile.OpenAsync(FileAccessMode.ReadWrite))
{
await httpMessage.Content.WriteToStreamAsync(fileStream);
}
using (var readStream = await tempFile.OpenAsync(FileAccessMode.Read))
{
var decoder = await BitmapDecoder.CreateAsync(readStream);
using (var writeStream = await file.OpenAsync(FileAccessMode.ReadWrite))
{
var encoder = await BitmapEncoder.CreateForTranscodingAsync(writeStream, decoder);
await encoder.FlushAsync();
}
}
}
}
return(true);
}
catch
{
return(false);
}
finally
{
try
{
if (tempFile != null)
{
await tempFile.DeleteAsync();
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("DownloadImageAsync. {0}", ex.Message);
}
}
}
private void OnSizeChanged(object sender, SizeChangedEventArgs e)
{
var imageSize = _image.DesiredSize;
if (imageSize.Width > 0 && imageSize.Height > 0)
{
if (_isHttpSource && BitmapCache.GetSizeLevel(_currentSize) != BitmapCache.GetSizeLevel(imageSize))
{
_currentSize = imageSize;
RefreshImage();
}
}
}
private async Task LoadImageAsync()
{
if (!_isLoadingImage && _uri != null)
{
_isLoadingImage = true;
if (_isHttpSource)
{
_image.Source = await BitmapCache.LoadFromCacheAsync(_uri, (int)_currentSize.Width, (int)_currentSize.Height);
}
else
{
_image.Source = new BitmapImage(_uri);
}
_isLoadingImage = false;
}
}
private async void RefreshSourceUri(Uri uri)
{
try
{
if (!Windows.ApplicationModel.DesignMode.DesignModeEnabled)
{
uri = await BitmapCache.GetImageUriAsync(uri, (int)_currentSize.Width, (int)_currentSize.Height);
}
if (uri != null)
{
this.SetImage(new BitmapImage(uri));
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("RefreshSourceUri. {0}", ex.Message);
}
}