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Stopping SoundPlayer from a different thread while it's playing

For the sake of making a (shuffled) playlist, I've made a separate thread in which I load and play each song in the playlist. The background stuff (wav files, file paths, playlists and shuffling) all work without a hitch.
The issue is that I have 2 windows, each of which can close and open the other. Each window has a different playlist, and when I switch to the other window, I want my static SoundPlayer to stop playing, then start playing the new playlist.
This currently isn't working: currently, the application waits until the current track is finished before displaying the next window and starting the other playlist. Yes, the entire application waits on this.
I'm new to thread coding, so I'm not really sure what to do. The two methods of stopping this I've tried so far have been SoundPlayer.Stop() and Thread.Abort(). Neither changes the situation at all.
In each window:
Thread playlistThread;
public Window()
{
InitializeComponent();
MusicPlayer.music.Stop();
playlistThread = new Thread(() => MusicPlayer.PlayPlaylist(MusicPlayer.ShufflePlaylist(MusicPlayer.PlaylistFromType("[insert track type]"), random)));
playlistThread.Start();
PlayPlaylist which I will show next takes a List of strings, so don't worry about the Thread line, it's just a few sections put into one. The properties after that simply generate that list, and again, that all works, but I can show it if anyone thinks it's necessary. Here is the PlayPlaylist method:
public static void PlayPlaylist(List<string> tracks)
{
for (int i = 0; i < tracks.Count; i++)
{
music.SoundLocation = tracks[i];
music.PlaySync();
}
}

Here's the answer I worked out:
public static void PlayTrack(List<string> tracks, int i)
{
while (true)
{
if (i == tracks.Count)
{
tracks = MusicPlayer.ShufflePlaylist(tracks, MusicPlayer.random);
i = 0;
}
music.SoundLocation = tracks[i];
int l = SoundInfo.GetSoundLength(tracks[i]);
music.Play();
while (l > 0)
{
Thread.Sleep(1000);
l -= 1000;
}
i++;
}
}
The SoundInfo class with its GetSoundLength method I found here.
The reason this method works while others do not is because of how Play() and PlaySync() work. PlaySync() plays the entire .wav file in the current thread, with nothing else running until it finishes. Thus, even SoundPlayer.Stop() and Thread.Abort() do not work, as they insert a new line after the current one.
By running this method in a new thread, you avoid PlaySync() giving you that issue. However, it will still be impossible to stop the track ahead of time using PlaySync(). This is why you use Play() instead.
Therein lies a second issue, however: Play() plays the track in its own thread, meaning the rest of the code will continue. This is a big risk if you're wanting to do anything only after the current track finishes.
The answer is to calculate the length of the track you're going to play. Then simply create a while loop, running until l (given by GetSoundLength()) reaches 0. In each pass through the loop the thread (separate from your window's main thread) sleeps for 1 second. This is fine on the CPU and means that every second extra code, such as SoundPlayer.Stop(), can be injected into the thread.

C# Trouble with event handlers on dieing threads

First of all my Main is STAThread and i am not able to change this without facing problems with the rest of my code.
So, I am currently using Rapi2 To pull and push files between my Pda and Computer. Now since there is quite a bit of number crunching i would like to do this on a separate thread. First wat i do is create an RemoteDeviceManager and then make an Event Handler for when a device connects.
public void Initialize()
{
_deviceManager = new RemoteDeviceManager();
_deviceManager.DeviceConnected += DeviceConnected;
}
As you can see when my device connects it triggers DeviceConnected.
This is the class that i end up pulling and pushing a database and do some number work.
private void DeviceConnected(object sender, RemoteDeviceConnectEventArgs e)
{
if (e.Device == null) return;
... (unimportant code)
}
Now the problem here is that i would want to run the code inside DeviceConnected in a new thread but i am unable to access e inside the new thread since it was initialized outside that thread
So now wat i tried was make a new thread before calling Initialize.
public Watcher()
{
_dataThread = new Thread(Initialize);
_dataThread.IsBackground = true;
_dataThread.Name = "Data Thread";
_dataThread.SetApartmentState(ApartmentState.MTA);
_dataThread.Start();
}
But the thread dies and thus never fires my event handler.
I tried many different ways to make it work or keep my thread alive but without any success. I hope someone here is able to give me some hints.

Console "Hangs" when GUI launches

Before I start, I'd like to appologize for any... idiocy... that I may show when asking this question, I'm trying to learn C# after coming from Java, and just wanted to jump right into it!
I'm working on a project that is designed to take commands through the console, such as "play batman begins" and it'll start playing the movie Batman Begins. It also takes commands for music, etc. With this setup, my goal is to have it voice controlled, so I'm not really concerned with using a GUI instead of the console. When I have the program play a movie, it loads up a GUI window with no border, no content, and the constructor that it uses is:
public MainWindow(MediaPlayer player)
{
InitializeComponent();
VideoDrawing drawing = new VideoDrawing { Rect = new Rect(0, 0, 800, 600), Player = player };
DrawingBrush brush = new DrawingBrush(drawing);
Background = brush;
}
The MediaPlayer is controlled from the main function (for now). My code to load the video and run it is:
MediaPlayer mp = new MediaPlayer();
mp.Open(new Uri("C:\\test.mp4", UriKind.RelativeOrAbsolute));
VideoDrawing vidDrawing = new VideoDrawing();
vidDrawing.Rect = new Rect(0, 0, 100, 100);
vidDrawing.Player = mp;
DrawingBrush DBrush = new DrawingBrush(vidDrawing);
videoPanel = new MainWindow(mp); // GUI panel to play the video on, constructor is listed above
play();
new System.Windows.Application().Run(videoPanel);
As I'm new to C# and all, the way I got the GUI to work with this is by starting a new WPF project, creating the GUI and writing the code, then copy paste the xaml and cs files into my project (cause I'm a noob, I'm sorry). MAYBE this is causing the problem.
This code works (mostly) fine. When I run my program, it loads the video file, opens the Window, and plays the video on the screen while playing the sound too. However, when it starts the video, the GUI "hangs" and doesnt accept any input's OR outputs, but it's not frozen as the cursor is still flashing. I'm not sure why this is.
I've tried threading almost anything I can think of, but I get errors with that. I've tried localizing the loading to the GUI window itself, however it still hangs the console. I've been searching online for all sorts of things for the past few days and cant find a solution, so I turned here!
My program has a lot more classes and stuff going on, so I had to throw all this stuff together, and double check, so if I'm missing something or made a stupid please let me know and I can fix it. As I'm still kinda new to C# (but not new to programming) I may have missed something in my question details as well.
I'm wondering if the solution is to make it ALL GUI based, instead of hybrid console and GUI? Because of the information I've found online it looks like there can be some annoying... discrepancies... between the two types of threads?
Anyway, any help would be great, I've spent the past 3 days trying to debug this and haven't made any progress. If it helps, there's a link to the repo here! Thanks :)
EDIT: I made some changes while waiting for a response, primarily changing the way it draws to the GUI. Originally I had it painting to the background, but now have made it handle through a MediaElement. This is the whole class for my window now:
public partial class MainWindow : Window
{
public MainWindow(string dir)
{
InitializeComponent();
video.Source = new Uri(dir); //video is the name of my MediaElement
}
public void pause(){
video.Pause();
}
public void resume()
{
video.Play();
}
public void stop()
{
video.Stop();
this.Close();
}
public void volume(int i)
{
video.Volume = i;
}
}
This did NOT fix the console Hang, however this made everything much more centralized so as to make debugging easier. Hope this may help!

Consider converting this to a WPF-application, it will make things easier.
Anyway, you can still work with GUI without locking console, but you must execute GUI-related stuff on a separate dedicated STA thread. Since you are using WPF, this helper should be useful (this code is not production-quality, but works):
static class UIThread
{
private static Dispatcher _dispatcher;
public static void Start()
{
using(var wh = new ManualResetEvent(false))
{
var thread = new Thread(ThreadProc)
{
IsBackground = true,
};
thread.SetApartmentState(ApartmentState.STA);
thread.Start(wh);
wh.WaitOne();
}
}
private static void ThreadProc(object arg)
{
var wh = (EventWaitHandle)arg;
_dispatcher = Dispatcher.CurrentDispatcher;
wh.Set();
Dispatcher.Run();
}
public static Dispatcher Dispatcher
{
get { return _dispatcher; }
}
}
This helper provides you with a reference to a Dispatcher object, which is used to execute methods on UI thread.
All communication with UI thread should be done through Dispatcher.Invoke() or Dispatcher.BeginInvoke() methods. Note that since we now have several threads, MediaPlayer objects must be created on the UI thread. You can still hold it's reference on any thread you want, but any method calls to MediaPlayer object must go through Dispatcher.
Things to change:
add a UIThread.Start(); call before any attempts to use Dispatcher. Beginning of Main() method is a good place to do this.
MediaPlayer objects should be created like this: mediaPlayer = UIThread.Dispatcher.Invoke(() => new Media());
any UI-related code should go to Dispatcher.Invoke() or Dispatcher.BeginInvoke(): UIThread.Dispatcher.BeginInvoke(() => playVideo(#"C:\video.avi"));
Update
Also change new System.Windows.Application().Run(videoPanel); to simple videoPanel.Show(). Application.Run() blocks until the window is closed.

Stop SoundPlayer on mouseUp event

tl;dr version: How can I start playing a sound in the MouseDown event of a WinForms button and stop it from playing in the same button's MouseUp event?
Intermediate C# dev here and I've been trying to write a simple Simon clone.
I'm currently stuck trying to make it play the sound for the colored button only while the user is clicking the button. (I use "button" and "tile" interchangeably. Both refer to the colored button the user will press on the form)
I originally tried this:
public partial class frmMain : Form
{
private SoundPlayer soundPlayer;
private void btnGreenTile_MouseDown(object sender, MouseEventArgs e)
{
soundPlayer = new SoundPlayer(Properties.Resources.greenTileSound)
soundPlayer.Play();
}
private void btnGreenTile_MouseUp(object sender, MouseEventArgs e)
{
soundPlayer.Stop();
}
}
But this didn't stop the sound because the MouseUp event didn't fire due to MouseDown not being finished (still playing the sound which is like 5 seconds long in case someone holds the button for longer than a simple click). As mentioned by Luis Tellez in the comments, SoundPlayer plays the sound on it a new thread...so I have no idea why this code doesn't work now.
So I looked into multithreading and tried this:
public partial class frmMain : Form
{
private Thread soundThread = new Thread(new ParameterizedThreadStart(PlaySound));
// Create stream objects for each sound (needed to allow SoundPlayer to use Resources)
private Stream greenTileSound = Properties.Resources.greenTilePress;
private Stream redTileSound = Properties.Resources.redTilePress;
private Stream yellowTileSound = Properties.Resources.yellowTilePress;
private Stream blueTileSound = Properties.Resources.blueTilePress;
public frmMain()
{
InitializeComponent();
}
private void btnGreenTile_MouseDown(object sender, MouseEventArgs e)
{
soundThread.Start(greenTileSound);
}
private void btnGreenTile_MouseUp(object sender, MouseEventArgs e)
{
soundThread.Abort();
}
// Have to use object as parameter because ParamterizedThreadStart() only takes object arguments
private static void PlaySound(object soundToPlay)
{
SoundPlayer soundPlayer = new SoundPlayer((Stream)soundToPlay);
soundPlayer.Play();
}
}
With the above code, it does not stop playing the sound on MouseUp, and even better it throws a ThreadStateException with the message "Thread is running or terminated; it cannot restart."
As you can probably tell, I only just learned about multithreading while trying to write this code. I have to use ParameterizedThreadStart because the method it calls when the thread starts, PlaySound(), needs to pass a parameter to soundPlayer with the resource corresponding to the colored button that was pressed by the player (a .wav file).
I then thought maybe I should try using soundThread.Suspend() instead of soundThread.Abort() but Suspend is deprecated...
Can anyone point me in the right direction to get the sound to stop on MouseUp? Do I need to work with multithreading? I think my problem just comes down to logic but I am fully stuck. Thank you for any and all help! :)
As a side note, I'm kind of surprised that this question or something similiar has not been asked yet (at least I couldn't find it with google searches or stackExchange searches).

You can see in the documentation that the play() method run in other thread, you can do something else after it and it should run, so your problem with the first approach is something different from what you were thinking.
The Play method plays the sound using a new thread. If you call Play
before the .wav file has been loaded into memory, the .wav file will
be loaded before playback starts. You can use the LoadAsync or Load
method to load the .wav file to memory in advance. After a .wav file
is successfully loaded from a Stream or URL, future calls to playback
methods for the SoundPlayer will not need to reload the .wav file
until the path for the sound changes. If the .wav file has not been
specified or it fails to load, the Play method will play the default
beep sound.
http://msdn.microsoft.com/en-us/library/system.media.soundplayer.play%28v=vs.110%29.aspx

Windows Phone 7 Multiple Sounds Lag

I'm making a drum machine. From what I've read, it looks like the XNA SoundEffect class runs based on a timer, which causes a noticeable lag, and stops the rhythm being smooth.
I tried to use MediaElement, 'til I found out you cannot play multiple sounds at the same time.
Are there any workarounds for this? The sounds are handled by a timer, and need to play instantly.

I've done some in-game use of the XNA SoundEffect class and not seen any lag when responding to user events - e.g. button presses - especially when the sound effect is pre-loaded from resources.
The XNA class is designed to be used for sound effects - so it should be ideal for a single drum machine hit.
If you then see problems with timing on IsLooping, then I guess you'll have to implement your own timer to trigger new instances - but my advice would be to try it first.
Hope that helps

I've been using some sound in my app and I used the code from the example given on the msdn code samples website: http://msdn.microsoft.com/en-us/library/ff431744(v=vs.92).aspx
It looks like they are updating the timer every 50ms. Also note that the SoundEffect variables (coyoteSound and birdSound) are private data members where they only load once. The event handler on the button clicks simply call SoundEffect.play().
public MainPage()
{
InitializeComponent();
LoadSound("Resources/NightAmbientCreatureOneShot_01.wav", out coyoteSound);
LoadSound("Resources/AfternoonAmbientBirdOneShot_09.wav", out birdSound);
LoadSoundInstance("Resources/NightAmbienceSimple_01.wav", out ambienceSound, out ambienceInstance);
// Set the volume a little lower than full so it becomes the background.
ambienceInstance.Volume = 0.8f;
// Turn on looping so it runs continually in the background.
ambienceInstance.IsLooped = true;
// Timer to simulate the XNA game loop (SoundEffect classes are from the XNA Framework)
DispatcherTimer XnaDispatchTimer = new DispatcherTimer();
XnaDispatchTimer.Interval = TimeSpan.FromMilliseconds(50);
// Call FrameworkDispatcher.Update to update the XNA Framework internals.
XnaDispatchTimer.Tick += delegate { try { FrameworkDispatcher.Update(); } catch { } };
// Start the DispatchTimer running.
XnaDispatchTimer.Start();
}