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Cannot get Thread and animation Rotation to work

This is my control:
I am getting this to rotate, with this code:
Global variable, bool IsTriangleAnimRunning = false;
And the rest of the code:
public void AnimateTriangle()
{
var rotation = (int)((100 / 100d) * 45 * 1); // Max 45 degree rotation
var duration = (int)(750 * (100 / 100d)); // Max 750ms rotation
while (IsTriangleAnimRunning != false)
{
MyTriangle.Dispatcher.BeginInvoke(
(Action)(() =>
{
var anim = new DoubleAnimation
{
To = rotation,
Duration = new Duration(TimeSpan.FromMilliseconds(duration)),
AutoReverse = true
};
var rt = new RotateTransform();
MyTriangle.RenderTransform = rt;
rt.BeginAnimation(RotateTransform.AngleProperty, anim);
}), DispatcherPriority.ContextIdle);
Thread.Sleep(duration * 2);
}
}
The event handler for the button, that triggers the animation:
public void HandleTriangleEvents(object sender, RoutedEventArgs a)
{
Thread t_triagle = new Thread(new ThreadStart(this.AnimateTriangle));
Button btn = (Button)sender;
if (btn.Name == "btnStartTriangleAnim")
{
IsTriangleAnimRunning = true;
btnStartTriangleAnim.IsEnabled = false;
t_triagle.Start();
}
else
{
IsTriangleAnimRunning = false;
btnStartTriangleAnim.IsEnabled = true;
t_triagle.Abort();
}
}
It behaves in an unatural way, because, when I stop it, it resets to its regular position. I am assuming it, does this for some reason, that I cannot understand. Also, for some reason, this code does not get it to run constantly, but only once.
Desired functionality:
If, I hit start button, run the thread and keep on rotating, while thread is running. If, I hit, stop, then stop in the current state of rotation. If I hit start, run the thread again and keep rotating back and forth.
--
Tested with Task Async, runs slower and doesn't repeat.
private async Task AnimateTriangle()
{
double rotation = 45d;
double duration = 100d;
var anim = new DoubleAnimation
{
To = rotation,
Duration = TimeSpan.FromMilliseconds(duration),
AutoReverse = true,
RepeatBehavior = RepeatBehavior.Forever
};
var transform = MyTriangle.RenderTransform as RotateTransform;
await Task.Factory.StartNew(() =>
{
while (IsTriangleAnimRunning != false)
{
MyTriangle.Dispatcher.Invoke(() =>
{
if (transform == null)
{
transform = new RotateTransform();
MyTriangle.RenderTransform = transform;
}
transform.BeginAnimation(RotateTransform.AngleProperty, anim);
}, DispatcherPriority.ContextIdle);
if (IsTriangleAnimRunning == false)
{
MyTriangle.Dispatcher.Invoke(() =>
{
if (MyTriangle.RenderTransform is RotateTransform)
{
var angle = transform.Angle; // current animated value
transform.Angle = angle;
transform.BeginAnimation(RotateTransform.AngleProperty, null);
}
}, DispatcherPriority.ContextIdle);
}
}
});
}

You do not need to start a thread.
Start an animation that runs forever, until you reset it by setting a null animation.
Before you reset it, explicitly set the value of the target property to the current animated value.
Reuse the existing RotateTransform instead of re-assigning one each time you start the animation.
private void StartButtonClick(object sender, RoutedEventArgs e)
{
double rotation = 45d;
double duration = 750d;
var anim = new DoubleAnimation
{
To = rotation,
Duration = TimeSpan.FromMilliseconds(duration),
AutoReverse = true,
RepeatBehavior = RepeatBehavior.Forever
};
var transform = MyTriangle.RenderTransform as RotateTransform;
if (transform == null)
{
transform = new RotateTransform();
MyTriangle.RenderTransform = transform;
}
transform.Angle = 0d;
transform.BeginAnimation(RotateTransform.AngleProperty, anim);
}
private void StopButtonClick(object sender, RoutedEventArgs e)
{
if (MyTriangle.RenderTransform is RotateTransform transform)
{
var angle = transform.Angle; // current animated value
transform.Angle = angle;
transform.BeginAnimation(RotateTransform.AngleProperty, null);
}
}

C# won't allow me to add event handler to a button into a form class

This is a C# web form project I am starting with after a long time away from IDE coding...
I am trying to make a simple custom dialog box class. This is my code.
public static class Dialogo
{
public static int show ()
{
Form dialogo = new Form();
dialogo.Width = 300;
dialogo.Height = 300;
Button btnSim = new Button() { Text = "Sim", Left = 30, Width = 100 };
Button btnNao = new Button() { Text = "Não", Left = 150, Width = 100 };
dialogo.Controls.Add(btnSim);
dialogo.Controls.Add(btnNao);
dialogo.ShowDialog();
// the following two lines are the problematic ones
btnSim += new EventHandler(btnSim_Click);
btnNao += new EventHandler(btnNao_Click);
return -1;
}
}
It's underlining the text within parenthesis and the message says:
The name btnSim_Click' does not exist in the current context
The problem is that I tried to add the following in my code but it doesn't let me put it anywhere (it always says that is something wrong):
private int btnNao_Click (object sender, EventArgs e)
{
return 0;
}
private int btnSim_Click (object sender, EventArgs e)
{
return 1;
}
My objective is that each of the both buttons btnSim and btnNao return a different value (say 1 and 0).
What am I doing wrong?

EventHandler is a delegate for a method that returns void.
Your methods return int.
Try something like this:
public static int show()
{
int returnValue = -1;
using (Form dialogo = new Form())
{
dialogo.Width = 300;
dialogo.Height = 300;
Button btnSim = new Button() { Text = "Sim", Left = 30, Width = 100 };
Button btnNao = new Button() { Text = "Não", Left = 150, Width = 100 };
dialogo.Controls.Add(btnSim);
dialogo.Controls.Add(btnNao);
btnSim.Click += (s, e) => { returnValue = 0; dialogo.DialogResult = DialogResult.OK; };
btnNao.Click += (s, e) => { returnValue = 1; dialogo.DialogResult = DialogResult.OK; };
dialogo.Disposed += (s, e) =>
{
btnSim?.Dispose();
btnSim = null;
btnNao?.Dispose();
btnNao = null;
};
dialogo.ShowDialog();
}
return returnValue;
}

How can an animation be added properly to a CALayer when using AVAssetExportSession in Xamarin.ios?

I need your help regarding an animation I want to apply to an overlay image I add to a mp4 video. To add an overlay on a video, I followed Ray Wenderlich tutorials here: https://www.raywenderlich.com/30200/avfoundation-tutorial-adding-overlays-and-animations-to-videos. At the end of that link, an animation is created on an overlay.
Ray Wenderlich is not coding with c# but I do since I use Xamarin to create my app.
Using the animation, the overlay is supposed to fade away during the very first seconds of the video. But nothing happens. I mean nothing animated happens except for the video: the overlay is well put on top of the video but it does not fade away.
Most of the posts I read about animations and CALayer create an animation within a UIView.
So I am asking myself: is the animation not working because I use c# or did I write something wrong?
Can somebody help me with this, please?
This is the function I wrote:
public static void addFadeOverlayAtTheBeginning (NSUrl source, String overlay, long secondsToFade, NSUrl destination)
{
AVUrlAsset videoAsset = new AVUrlAsset(source);
if (secondsToFade > videoAsset.Duration.Seconds)
secondsToFade = (long)videoAsset.Duration.Seconds;
CALayer overlayLayer = CALayer.Create();
UIImage image = new UIImage(overlay);
image.CreateResizableImage(new UIEdgeInsets(0, 0, videoAsset.NaturalSize.Width, videoAsset.NaturalSize.Height));
overlayLayer.Contents = image.CGImage;
overlayLayer.Frame = new CGRect(0, 0, videoAsset.NaturalSize.Width, videoAsset.NaturalSize.Height);
overlayLayer.MasksToBounds = true;
CABasicAnimation animation = CABasicAnimation.FromKeyPath(#"opacity");
animation.BeginTime = 0; // GetSeconds(image.CGImage.StartTime);
animation.Duration = secondsToFade;
animation.SetFrom (NSNumber.FromFloat (1));
animation.SetTo (NSNumber.FromFloat(0));
overlayLayer.AddAnimation(animation, #"opacity");
AVMutableComposition videoComposition = AVMutableComposition.Create();
AVMutableCompositionTrack track = videoComposition.AddMutableTrack(AVMediaType.Video, 0);
AVAssetTrack sourceVideoTrack = videoAsset.TracksWithMediaType(AVMediaType.Video)[0];
CMTimeRange timeRangeInAsset = new CMTimeRange();
timeRangeInAsset.Start = CMTime.Zero;
timeRangeInAsset.Duration = videoAsset.Duration;
NSError videoInsertError = null;
track.InsertTimeRange(timeRangeInAsset, sourceVideoTrack, CMTime.Zero, out videoInsertError);
track.PreferredTransform = sourceVideoTrack.PreferredTransform;
CALayer parentLayer = CALayer.Create();
CALayer videoLayer = CALayer.Create();
parentLayer.Frame = new CGRect(0, 0, videoAsset.NaturalSize.Width, videoAsset.NaturalSize.Height);
videoLayer.Frame = new CGRect(0, 0, videoAsset.NaturalSize.Width, videoAsset.NaturalSize.Height);
parentLayer.AddSublayer(videoLayer);
parentLayer.AddSublayer(overlayLayer);
//parentLayer.AddAnimation(animation, "opacity");
AVMutableVideoComposition animationComposition = AVMutableVideoComposition.Create(); //videoComposition
animationComposition.AnimationTool = AVVideoCompositionCoreAnimationTool.FromLayer(videoLayer, parentLayer);
animationComposition.RenderSize = videoAsset.NaturalSize;
animationComposition.FrameDuration = new CMTime(1, 30);
AVMutableVideoCompositionInstruction instruction = AVMutableVideoCompositionInstruction.Create() as AVMutableVideoCompositionInstruction;
CMTimeRange timeRangeInstruction = new CMTimeRange();
timeRangeInstruction.Start = CMTime.Zero;
timeRangeInstruction.Duration = videoComposition.Duration;
instruction.TimeRange = timeRangeInstruction;
AVMutableVideoCompositionLayerInstruction layerInstruction = AVMutableVideoCompositionLayerInstruction.FromAssetTrack(track);
CMTimeRange timeRangeFading = new CMTimeRange();
timeRangeFading.Start = CMTime.Zero;
timeRangeFading.Duration = new CMTime(secondsToFade, 1);
//layerInstruction.SetOpacityRamp(1, 0, timeRangeFading);
instruction.LayerInstructions = new AVVideoCompositionLayerInstruction[] { layerInstruction };
List<AVVideoCompositionInstruction> instructions = new List<AVVideoCompositionInstruction>();
instructions.Add(instruction);
animationComposition.Instructions = instructions.ToArray();
if (File.Exists(destination.Path))
File.Delete(destination.Path);
AVAssetExportSession exporter = new AVAssetExportSession(videoComposition, AVAssetExportSession.PresetHighestQuality);
exporter.OutputUrl = destination;
exporter.VideoComposition = animationComposition;
exporter.OutputFileType = AVFileType.Mpeg4;
exporter.ExportAsynchronously(() => {
VideoManagement.state ++;
AVAssetExportSessionStatus status = exporter.Status;
Console.WriteLine("addFadeOverlayAtTheBeginning Done. Status: " + status.ToString());
switch (status)
{
case AVAssetExportSessionStatus.Completed:
Console.WriteLine("Sucessfully Completed");
if (File.Exists(destination.Path))
{
Console.WriteLine(String.Format("Saved to {0}", destination.Path));
}
else
Console.WriteLine("Failed");
break;
case AVAssetExportSessionStatus.Cancelled:
break;
case AVAssetExportSessionStatus.Exporting:
break;
case AVAssetExportSessionStatus.Failed:
Console.WriteLine("Task failed => {0}", exporter.Error);
Console.WriteLine(exporter.Error.Description);
break;
case AVAssetExportSessionStatus.Unknown:
break;
case AVAssetExportSessionStatus.Waiting:
break;
default:
break;
}
});
}

OK. Found it.
Apparently, animation.BeginTime = 0; is not supported. I changed it to 0.01 and everything works fine.
double Epsilon = 0.01;
if (secondsToFade > videoAsset.Duration.Seconds - Epsilon)
secondsToFade = videoAsset.Duration.Seconds - Epsilon;
CALayer overlayLayer = CALayer.Create();
UIImage image = new UIImage(overlay);
image.CreateResizableImage(new UIEdgeInsets(0, 0, videoAsset.NaturalSize.Width, videoAsset.NaturalSize.Height));
overlayLayer.Contents = image.CGImage;
overlayLayer.Frame = new CGRect(0, 0, videoAsset.NaturalSize.Width, videoAsset.NaturalSize.Height);
overlayLayer.MasksToBounds = true;
//On crée l'animation pour le CAlayer
CABasicAnimation animation = CABasicAnimation.FromKeyPath(#"opacity");
animation.BeginTime = Epsilon;
animation.Duration = secondsToFade;
animation.SetFrom (NSNumber.FromFloat (1));
animation.SetTo (NSNumber.FromFloat(0));
animation.FillMode = CAFillMode.Forwards;
animation.RemovedOnCompletion = false;

WPF Mediaelement.Position is not working

What I need is to set the Position property on WPF's MediaElement control. But when I play the video, (either via Play() or through some kind of animation on Opacity) it is is not working at all. It is showing 00:00:00 time, but I would expect it to be set to 00:00:05.
I have hard-coded Position value and it is not working at all.
Just In case I am going to put all my code I have so u can see the whole animation logic.
Any clue?
public partial class CrossFadeTransition : UserControl
{
DoubleAnimation _doubleAnimationFrontPlayer = new DoubleAnimation();
DoubleAnimation _doubleAnimationBackPlayer = new DoubleAnimation();
Storyboard _sb1 = new Storyboard();
Storyboard _sb2 = new Storyboard();
public TimeSpan Duration = TimeSpan.FromSeconds(2);
public Dictionary<string, Position2D> PlayerPosition { set; get; }
public CrossFadeTransition()
{
InitializeComponent();
Player1.LoadedBehavior = MediaState.Manual;
Player1.UnloadedBehavior = MediaState.Stop;
Player2.LoadedBehavior = MediaState.Manual;
Player2.UnloadedBehavior = MediaState.Stop;
PlayerPosition = new Dictionary<string, Position2D>();
PlayerPosition.Add("Player1", Position2D.Front);
PlayerPosition.Add("Player2", Position2D.Back);
}
Position2D positionPlayer1;
Position2D positionPlayer2;
public void Stop()
{
if (Player1.IsEnabled)
Player1.Stop();
if (Player2.IsEnabled)
Player2.Stop();
}
public void Start(Uri uri, int? position)
{
try
{
positionPlayer1 = PlayerPosition["Player1"];
positionPlayer2 = PlayerPosition["Player2"];
if (positionPlayer1 == Library.Position2D.Back)
{
Player1.Source = uri;
if (Player1.IsEnabled)
Player1.Stop();
Player1.Position = TimeSpan.FromSeconds(5); // IT IS NOT WORKING !!!
Player1.Play();
}
if (positionPlayer2 == Library.Position2D.Back)
{
Player2.Source = uri;
if (Player2.IsEnabled)
Player2.Stop();
Player2.Position = TimeSpan.FromSeconds(5); // IT IS NOT WORKING !!!
Player2.Play();
}
_sb1.Children.Clear();
_sb2.Children.Clear();
if (positionPlayer1 == Position2D.Front)
{
_doubleAnimationFrontPlayer.From = 1;
_doubleAnimationFrontPlayer.To = 0;
_doubleAnimationFrontPlayer.Duration = new Duration(Duration);
PlayerPosition["Player1"] = Position2D.Back;
}
else if (positionPlayer1 == Position2D.Back)
{
_doubleAnimationFrontPlayer.From = 0;
_doubleAnimationFrontPlayer.To = 1;
_doubleAnimationFrontPlayer.Duration = new Duration(Duration);
PlayerPosition["Player1"] = Position2D.Front;
}
if (positionPlayer2 == Position2D.Front)
{
_doubleAnimationBackPlayer.From = 1;
_doubleAnimationBackPlayer.To = 0;
_doubleAnimationBackPlayer.Duration = new Duration(Duration);
PlayerPosition["Player2"] = Position2D.Back;
}
else if (positionPlayer2 == Position2D.Back)
{
_doubleAnimationBackPlayer.From = 0;
_doubleAnimationBackPlayer.To = 1;
_doubleAnimationBackPlayer.Duration = new Duration(Duration);
PlayerPosition["Player2"] = Position2D.Front;
}
_sb1.Children.Add(_doubleAnimationFrontPlayer);
Storyboard.SetTargetProperty(_doubleAnimationFrontPlayer, new PropertyPath("(Panel.Opacity)"));
Storyboard.SetTarget(_doubleAnimationFrontPlayer, Player1);
_sb1.Completed += _sb1_Completed;
_sb1.Begin();
//
_sb2.Children.Add(_doubleAnimationBackPlayer);
Storyboard.SetTargetProperty(_doubleAnimationBackPlayer, new PropertyPath("(Panel.Opacity)"));
Storyboard.SetTarget(_doubleAnimationBackPlayer, Player2);
_sb2.Completed += _sb2_Completed;
_sb2.Begin();
}
catch (Exception)
{
throw;
}
}
void _sb2_Completed(object sender, EventArgs e)
{
_sb2.Completed -= _sb2_Completed;
Debug.WriteLine("Player2 COMPLETED " + DateTime.Now.TimeOfDay);
if (positionPlayer2 == Position2D.Front)
{
Player2.Stop();
}
}
void _sb1_Completed(object sender, EventArgs e)
{
_sb1.Completed -= _sb1_Completed;
Debug.WriteLine("Player1 COMPLETED " + DateTime.Now.TimeOfDay);
if (positionPlayer1 == Position2D.Front)
{
Player1.Stop();
}
}
}
I have tried to do like
Player2.Play();
Player2.Pause();
Player2.Position = TimeSpan.FromSeconds(5); // IT IS NOT WORKING !!!
Player2.Play();
But no joy...

I found some solution. It is not completely ideal because sometimes it shows the first video frame, but at least it is working.
We need those events where we can apply new Position.
void Player2_MediaOpened(object sender, RoutedEventArgs e)
{
Player2.Position = new TimeSpan(0, 0, 7);
}
void Player1_MediaOpened(object sender, RoutedEventArgs e)
{
Player1.Position = new TimeSpan(0, 0, 7);
}
We have to close Mediaelement like this.
Player1.Stop();
Player1.Close();
Player1.Source = uri;
Player1.Play();
Have fun! (beer)

Event after double animation whilst keeping context

I am trying to create an animation but am having problems executing some code after the animation has occured. The animation code is as follows...
public static void Friend(Canvas canvas)
{
foreach (var element in canvas.Children.OfType<Image>())
{
var elementName = Regex.Split(element.Name, "_");
if (elementName[0] == "friend")
{
var slideDown = new DoubleAnimation
{
From = Canvas.GetBottom(element),
To = Canvas.GetBottom(element) - element.Height,
Duration = new Duration(TimeSpan.FromSeconds(1)),
AutoReverse = true
};
element.BeginAnimation(Canvas.BottomProperty, slideDown);
slideDown.Completed += (sender, e) => Test(sender, e, element, canvas);
}
}
}
The event to happen afterwards is...
var random = new Random();
element.Source = Core.StreamImage(Wardrobe.Friends[Wardrobe.RandomFriend()]);
Canvas.SetLeft(element, random.Next(0, (int)(canvas.ActualWidth - element.Width)));
// then reverse the previous animation.
As you can see, the event needs to keep the context of the animation in order for it to work but event handlers don't allow this. I have tried adding this code directly underneath the element.BeginAnimation but it is executed prematurely.
I have also tried splitting the parts of the animation up into seperate functions but of course you can't have multiple animations on one object as the functions don't get executed in order resulting in only the last section being played.

Here is the code i used to fix the problem i was having...
public static void Friend(Canvas canvas)
{
var random = new Random();
foreach (var element in canvas.Children.OfType<Image>())
{
var elementName = Regex.Split(element.Name, "_");
if (elementName[0] == "friend")
{
var slideDown = new DoubleAnimation
{
From = Canvas.GetBottom(element),
To = Canvas.GetBottom(element) - element.Height,
Duration = new Duration(TimeSpan.FromSeconds(1))
};
slideDown.Completed += (sender, e) =>
{
element.Source = Core.StreamImage(Wardrobe.Friends[Wardrobe.RandomFriend()]);
Canvas.SetLeft(element, random.Next(0, (int)(canvas.ActualWidth - element.Width)));
var slideUp = new DoubleAnimation
{
From = Canvas.GetBottom(element),
To = Canvas.GetBottom(element) + element.Height,
Duration = new Duration(TimeSpan.FromSeconds(1))
};
element.BeginAnimation(Canvas.BottomProperty, slideUp);
};
element.BeginAnimation(Canvas.BottomProperty, slideDown);
}
}
}

Try moving the event above the execution
public static void Friend(Canvas canvas)
{
foreach (var element in canvas.Children.OfType<Image>())
{
var elementName = Regex.Split(element.Name, "_");
if (elementName[0] == "friend")
{
var slideDown = new DoubleAnimation
{
From = Canvas.GetBottom(element),
To = Canvas.GetBottom(element) - element.Height,
Duration = new Duration(TimeSpan.FromSeconds(1)),
AutoReverse = true
};
slideDown.Completed += (sender, e) => Test(sender, e, element, canvas);
element.BeginAnimation(Canvas.BottomProperty, slideDown);
}
}
}
I'm not 100% but I think the Animation becomes Freezable after it executes, so we cant modify after
BTW, you can have multiple animations on a object but you need to use "StoryBoard".
Storyboard example:
var slideDown = new DoubleAnimation { From = 100, To = 200, Duration = new Duration(TimeSpan.FromSeconds(5)), AutoReverse = true };
var slideLeft = new DoubleAnimation { From = 100, To = 200, BeginTime = TimeSpan.FromSeconds(5), Duration = new Duration(TimeSpan.FromSeconds(5)), AutoReverse = true };
Storyboard storyBoard = new Storyboard();
storyBoard.Children.Add(slideDown);
storyBoard.Children.Add(slideLeft);
Storyboard.SetTargetName(slideDown, myCanvas.Name);
Storyboard.SetTargetName(slideLeft, myCanvas.Name);
Storyboard.SetTargetProperty(slideLeft, new PropertyPath(Canvas.LeftProperty));
Storyboard.SetTargetProperty(slideDown, new PropertyPath(Canvas.TopProperty));
myCanvas.BeginStoryboard(storyBoard);