/// <summary>
/// Called when image loading is done.
///
/// effects: switch the image loading state to Idle.
/// </summary>
private void ImageLoadingDone()
{
imageLoadingState = ImageLoadingState.Idle;
imageLoadingDone = null;
}
public void RefreshThumbnails(ImageCollection images)
{
if (imageLoadingState == ImageLoadingState.Loading ||
imageLoadingState == ImageLoadingState.CancelLoading)
{
CancelLoading(images);
return;
}
Debug.Assert(imageLoadingState == ImageLoadingState.Idle);
// Show them in list view.
Items.Clear();
ImageList imageListLarge = new ImageList();
imageListLarge.ColorDepth = ColorDepth.Depth24Bit;
imageListLarge.ImageSize = new Size( cxThumbnail, cyThumbnail);
LargeImageList = imageListLarge;
BeginUpdate();
// Add items first to prevent flickers.
foreach (ImageInfo imageFile in images)
{
ListViewItem item = new ListViewItem();
item.ImageIndex = -1;
item.Text = Path.GetFileName(imageFile.ImagePath);
item.Tag = imageFile;
Items.Add(item);
}
EndUpdate();
// Switch the state.
imageLoadingState = ImageLoadingState.Loading;
imageLoadingDone = new ThumbnailLoadingDoneDelegate(ImageLoadingDone);
// Use asynchronous delegate to load image thumbnails.
LoadThumbnailsDelegate loadThumbnails = new LoadThumbnailsDelegate(LoadThumbnails);
loadThumbnails.BeginInvoke( images, null, new Object());
}
private void CancelLoading(ImageCollection images)
{
imagesToRefresh = images;
// remove all attached ImageInfo before canceling the loading to prevent flash
foreach (ListViewItem item in Items)
{
item.Tag = null;
}
// change the status to cancel image loading
imageLoadingState = ImageLoadingState.CancelLoading;
// delay the refresh until image loading is canceled
imageLoadingDone = new ThumbnailLoadingDoneDelegate(ImageLoadingDoneAndRefresh);
}
