void SetImagePlaceholder()
{
if (Element.ImagePlaceholder != null)
{
var placeholder = Element.ImagePlaceholder as FileImageSource;
if (placeholder != null && placeholder.File != null)
{
var resourceID = UIHelper.GetDrawableResource(placeholder);
//Bitmap imageBitmap = BitmapFactory.DecodeResource(Context.Resources, resourceID);
//SetImageCorners(imageBitmap);
if (resourceID > 0)
{
Bitmap imageBitmap = ImageCache.Instance.Get(resourceID.ToString());
if (imageBitmap == null)
{
BitmapWorkerTask task = new BitmapWorkerTask(imageView, -1, -1, ImageCache.Instance);
imageView.SetImageDrawable(new AsyncDrawable(imageView.Resources, null, task));
task.Execute(resourceID);
task.Finished += (s, e) =>
SetImageCorners(e);
}
else
{
SetImageCorners(imageBitmap);
}
}
}
}
}
public AsyncDrawable(Resources res, Bitmap bitmap,
BitmapWorkerTask bitmapWorkerTask)
: base(res, bitmap)
{
bitmapWorkerTaskReference =
new WeakReference <BitmapWorkerTask>(bitmapWorkerTask);
}
public static bool CancelPotentialWork(int data, ImageView imageView)
{
BitmapWorkerTask bitmapWorkerTask = GetBitmapWorkerTask(imageView);
if (bitmapWorkerTask != null)
{
int bitmapData = bitmapWorkerTask.data;
// If bitmapData is not yet set or it differs from the new data
if (bitmapData == 0 || bitmapData != data)
{
// Cancel previous task
bitmapWorkerTask.Cancel(true);
}
else
{
// The same work is already in progress
return(false);
}
}
// No task associated with the ImageView, or an existing task was cancelled
return(true);
}
async void SetImageSource()
{
if (Element.Source != null)
{
if (Element.Source is UriImageSource)
{
isImageInitialSet = true;
var uri = Element.Source.GetValue(UriImageSource.UriProperty) as Uri;
var bitmap = await imageDownloader.GetImageAsync(uri);
SetImageCorners(bitmap);
}
else if (Element.Source is FileImageSource)
{
if ((Element.Width > 0 && Element.Height > 0) || (Element.WidthRequest > 0 && Element.HeightRequest > 0))
{
isImageInitialSet = true;
var source = Element.Source as FileImageSource;
if (source != null && source.File != null)
{
var resourceID = UIHelper.GetDrawableResource(source);
if (resourceID > 0)
{
Bitmap imageBitmap = ImageCache.Instance.Get(resourceID.ToString());
if (imageBitmap == null)
{
var width = BaseUIHelper.ConvertDPToPixels(Element.Width <= 0 ? Element.WidthRequest : Element.Width);
var height = BaseUIHelper.ConvertDPToPixels(Element.Height <= 0 ? Element.HeightRequest : Element.Height);
BitmapWorkerTask task = new BitmapWorkerTask(imageView, width, height, ImageCache.Instance);
imageView.SetImageDrawable(new AsyncDrawable(imageView.Resources, null, task));
task.Execute(resourceID);
task.Finished += (s, e) =>
SetImageCorners(e);
}
else
{
SetImageCorners(imageBitmap);
}
}
else
{
var imageBitmap = await BitmapFactory.DecodeFileAsync(source.File);
SetImageCorners(imageBitmap);
}
}
}
}
else if (Element.Source is StreamImageSource)
{
isImageInitialSet = true;
var source = Element.Source as StreamImageSource;
var cts = new System.Threading.CancellationTokenSource();
var str = await source.Stream(cts.Token);
using (var reader = new System.IO.BinaryReader(str))
{
var data = reader.ReadBytes((int)str.Length);
var bitmap = await BitmapFactory.DecodeByteArrayAsync(data, 0, data.Length);
SetImageCorners(bitmap);
}
}
}
else
{
if (Element.ImagePlaceholder == null)
{
imageView.SetImageBitmap(null);
}
}
}
private async void UpdateBitmap(Image previous = null)
{
if (Element == null || Control == null)
{
return;
}
Bitmap bitmap = null;
ImageSource source = Element.Source;
if (previous == null || !object.Equals(previous.Source, Element.Source))
{
SetIsLoading(true);
((CustomImageView)base.Control).SkipInvalidate();
// I'm not sure where this comes from.
// Control.SetImageResource(17170445);
if (BaseControl.ImagePlaceholder != null)
{
var placeholder = BaseControl.ImagePlaceholder as FileImageSource;
var resourceID = UIHelper.GetDrawableResource(placeholder);
if (resourceID > 0)
{
Bitmap imageBitmap = imageCache.Get(resourceID.ToString());
//imageBitmap = BitmapFactory.DecodeResource(Context.Resources, resourceID);
if (imageBitmap == null)
{
BitmapWorkerTask task = new BitmapWorkerTask(Control, -1, -1, imageCache);
Control.SetImageDrawable(new AsyncDrawable(Control.Resources, null, task));
task.Execute(resourceID);
task.Finished += (s, e) =>
{
Control.SetImageBitmap(e);
e.Dispose();
};
}
else
{
Control.SetImageBitmap(imageBitmap);
imageBitmap.Dispose();
}
}
}
if (source != null)
{
try
{
bitmap = await GetImageFromImageSource(source, Context);
}
catch (TaskCanceledException)
{
}
catch (IOException)
{
}
catch (NotImplementedException)
{
}
}
if (Element != null && object.Equals(Element.Source, source))
{
if (!_isDisposed)
{
if (bitmap == null && BaseControl.ImagePlaceholder != null)
{
}
else
{
Control.SetImageBitmap(bitmap);
}
if (bitmap != null)
{
bitmap.Dispose();
}
SetIsLoading(false);
((IVisualElementController)base.Element).NativeSizeChanged();
}
}
}
}
