protected void QueueImageLoadingTask(IImageLoaderTask task)
{
int position = Interlocked.Increment(ref _currentPosition);
var currentPendingTask = new PendingTask()
{
Position = position, ImageLoadingTask = task, FrameworkWrappingTask = CreateFrameworkTask(task)
};
PendingTask similarRunningTask = null;
lock (_pendingTasksLock)
{
similarRunningTask = PendingTasks.FirstOrDefault(t => t.ImageLoadingTask.Key == task.Key);
if (similarRunningTask == null)
{
Interlocked.Increment(ref _statsTotalPending);
PendingTasks.Add(currentPendingTask);
}
else
{
similarRunningTask.Position = position;
}
}
if (similarRunningTask == null || !currentPendingTask.ImageLoadingTask.CanUseMemoryCache)
{
TakeFromPendingTasksAndRun();
}
else
{
WaitForSimilarTaskFinished(currentPendingTask, similarRunningTask);
}
}
protected void QueueImageLoadingTask(IImageLoaderTask task)
{
int position = Interlocked.Increment(ref _currentPosition);
var currentPendingTask = new PendingTask()
{
Position = position, ImageLoadingTask = task, FrameworkWrappingTask = CreateFrameworkTask(task)
};
if (task.IsCancelled || task.IsCompleted || ExitTasksEarly)
{
task?.Dispose();
return;
}
PendingTask similarRunningTask = null;
lock (_pendingTasksLock)
{
if (!task.Parameters.Preload)
{
foreach (var pendingTask in PendingTasks.ToList()) // FMT: here we need a copy since cancelling will trigger them to be removed, hence collection is modified during enumeration
{
if (pendingTask.ImageLoadingTask != null && pendingTask.ImageLoadingTask.UsesSameNativeControl(task))
{
pendingTask.ImageLoadingTask.CancelIfNeeded();
}
}
EvictStaleTasks();
}
similarRunningTask = PendingTasks.FirstOrDefault(t => t.ImageLoadingTask.Key == task.Key);
if (similarRunningTask == null)
{
Interlocked.Increment(ref _statsTotalPending);
PendingTasks.Add(currentPendingTask);
}
else
{
similarRunningTask.Position = position;
}
}
if (PauseWork)
{
return;
}
if (similarRunningTask == null || !currentPendingTask.ImageLoadingTask.CanUseMemoryCache)
{
TakeFromPendingTasksAndRun();
}
else
{
WaitForSimilarTaskFinished(currentPendingTask, similarRunningTask);
}
}
public void AddTask(string taskName)
{
lock (Host)
{
PendingTasks.Add(
new ExecutingTask()
{
Client = null,
Complete = false,
TaskName = taskName
});
}
UpdateTaskAssignments();
}
protected async void WaitForSimilarTaskFinished(PendingTask currentPendingTask, PendingTask taskForSimilarKey)
{
Interlocked.Increment(ref _statsTotalWaiting);
if ((taskForSimilarKey?.FrameworkWrappingTask == null)
|| taskForSimilarKey.FrameworkWrappingTask.IsCanceled
|| taskForSimilarKey.FrameworkWrappingTask.IsFaulted)
{
lock (_pendingTasksLock)
{
Interlocked.Increment(ref _statsTotalPending);
PendingTasks.Add(currentPendingTask);
}
TakeFromPendingTasksAndRun();
return;
}
Logger.Debug(string.Format("Wait for similar request for key: {0}", taskForSimilarKey.ImageLoadingTask.Key));
await taskForSimilarKey.FrameworkWrappingTask.ConfigureAwait(false);
if ((currentPendingTask?.ImageLoadingTask == null) || currentPendingTask.ImageLoadingTask.IsCancelled)
return;
// Now our image should be in the cache
var cacheFound =
await currentPendingTask.ImageLoadingTask.TryLoadFromMemoryCacheAsync().ConfigureAwait(false);
if (!cacheFound)
{
if ((currentPendingTask?.ImageLoadingTask == null) || currentPendingTask.ImageLoadingTask.IsCancelled)
return;
lock (_pendingTasksLock)
{
Interlocked.Increment(ref _statsTotalPending);
PendingTasks.Add(currentPendingTask);
}
TakeFromPendingTasksAndRun();
}
else
{
currentPendingTask?.ImageLoadingTask?.Dispose();
}
}
/// <summary>
/// Starts the <see cref="AbortableTask">Task</see> using <see cref="TaskManager.TaskFactory">TaskFactory</see>
/// and adds it to the <see cref="TaskManager.Tasks">Tasks</see> collection or the
/// <see cref="TaskManager.PendingTasks">PendingTasks</see> collection if no threads are available.
/// </summary>
/// <param name="task"></param>
public void StartTask(AbortableTask task)
{
if (MaximumConcurrency <= RunningTasks.Count())
{
PendingTasks.Add(task);
}
else
{
Tasks.Add(task);
if (TaskFactory.Scheduler == null)
{
task.Task.Start();
}
else
{
task.Task.Start(TaskFactory.Scheduler);
}
}
}
protected void QueueImageLoadingTask(IImageLoaderTask task)
{
var position = Interlocked.Increment(ref _currentPosition);
var currentPendingTask = new PendingTask
{
Position = position,
ImageLoadingTask = task,
FrameworkWrappingTask = CreateFrameworkTask(task)
};
if (task.IsCancelled || task.IsCompleted || ExitTasksEarly)
{
task?.Dispose();
return;
}
PendingTask similarRunningTask = null;
lock (_pendingTasksLock)
{
if (!task.Parameters.Preload)
{
foreach (var pendingTask in PendingTasks.ToList())
// FMT: here we need a copy since cancelling will trigger them to be removed, hence collection is modified during enumeration
if ((pendingTask.ImageLoadingTask != null) &&
pendingTask.ImageLoadingTask.UsesSameNativeControl(task))
pendingTask.ImageLoadingTask.CancelIfNeeded();
EvictStaleTasks();
}
similarRunningTask = PendingTasks.FirstOrDefault(t => t.ImageLoadingTask.Key == task.Key);
if (similarRunningTask == null)
{
Interlocked.Increment(ref _statsTotalPending);
PendingTasks.Add(currentPendingTask);
}
else if (similarRunningTask.ImageLoadingTask != null)
{
if (task.Parameters.Priority.HasValue &&
(!similarRunningTask.ImageLoadingTask.Parameters.Priority.HasValue
||
(task.Parameters.Priority.Value > similarRunningTask.ImageLoadingTask.Parameters.Priority.Value)))
similarRunningTask.ImageLoadingTask.Parameters.WithPriority(task.Parameters.Priority.Value);
if (task.Parameters.OnDownloadProgress != null)
{
var similarTaskOnDownloadProgress =
similarRunningTask.ImageLoadingTask.Parameters.OnDownloadProgress;
similarRunningTask.ImageLoadingTask.Parameters.DownloadProgress(obj =>
{
similarTaskOnDownloadProgress?.Invoke(obj);
task.Parameters.OnDownloadProgress(obj);
});
}
}
}
if (PauseWork)
return;
if ((similarRunningTask == null) || !currentPendingTask.ImageLoadingTask.CanUseMemoryCache)
TakeFromPendingTasksAndRun();
else
WaitForSimilarTaskFinished(currentPendingTask, similarRunningTask);
}