C# c Android-ISurfaceTextureListener线程中断,然后在活动关闭时恢复
我有一个带有ISurfaceTextureListener的活动,该活动具有一个异步OnSurfaceTextureUpdated方法,在该方法中我调用异步SendPixel方法:C# c Android-ISurfaceTextureListener线程中断,然后在活动关闭时恢复,c#,android,multithreading,asynchronous,interruption,C#,Android,Multithreading,Asynchronous,Interruption,我有一个带有ISurfaceTextureListener的活动,该活动具有一个异步OnSurfaceTextureUpdated方法,在该方法中我调用异步SendPixel方法: public async void OnSurfaceTextureUpdated(SurfaceTexture surface) { bool sendPixel = false; [...] if (Settings.Pixel.period >= 0) {
public async void OnSurfaceTextureUpdated(SurfaceTexture surface)
{
bool sendPixel = false;
[...]
if (Settings.Pixel.period >= 0)
{
if (stopWatch.ElapsedMilliseconds >= Settings.Pixel.nextSending)
{
if (Settings.Pixel.period > 0)
Settings.Pixel.nextSending += Settings.Pixel.period * ((int)((stopWatch.ElapsedMilliseconds - Settings.Pixel.nextSending) / Settings.Pixel.period) + 1);
sendPixel = true;
}
}
[...]
if (sendPixel)
await SendPixel();
}
async Task SendPixel()
{
try
{
if (Ev3Messaging.IsConnected())
{
Color color = new Color(bm.GetPixel(Settings.Camera.viewport.X_VpToCv(Settings.Pixel.x), Settings.Camera.viewport.X_VpToCv(Settings.Pixel.y)));
Ev3Messaging.AddNumberMessage("MC_Hue", color.GetHue());
Ev3Messaging.AddNumberMessage("MC_Brightness", color.GetBrightness());
Console.WriteLine("SendPixel");
await Ev3Messaging.SendMessages();
Console.WriteLine("SendPixelEnd");
}
}
catch (Exception ex)
{
Console.WriteLine("Error SendPixel: " + ex.Message);
}
}
以下是异步SendPixel方法:
public async void OnSurfaceTextureUpdated(SurfaceTexture surface)
{
bool sendPixel = false;
[...]
if (Settings.Pixel.period >= 0)
{
if (stopWatch.ElapsedMilliseconds >= Settings.Pixel.nextSending)
{
if (Settings.Pixel.period > 0)
Settings.Pixel.nextSending += Settings.Pixel.period * ((int)((stopWatch.ElapsedMilliseconds - Settings.Pixel.nextSending) / Settings.Pixel.period) + 1);
sendPixel = true;
}
}
[...]
if (sendPixel)
await SendPixel();
}
async Task SendPixel()
{
try
{
if (Ev3Messaging.IsConnected())
{
Color color = new Color(bm.GetPixel(Settings.Camera.viewport.X_VpToCv(Settings.Pixel.x), Settings.Camera.viewport.X_VpToCv(Settings.Pixel.y)));
Ev3Messaging.AddNumberMessage("MC_Hue", color.GetHue());
Ev3Messaging.AddNumberMessage("MC_Brightness", color.GetBrightness());
Console.WriteLine("SendPixel");
await Ev3Messaging.SendMessages();
Console.WriteLine("SendPixelEnd");
}
}
catch (Exception ex)
{
Console.WriteLine("Error SendPixel: " + ex.Message);
}
}
ISurfaceTextureListener读取视频流,然后多次调用SendPixel方法。
问题是控制台很好地显示SendPixel,但不显示SendPixelEnd,并且不会引发错误。
之后,当我关闭“活动”时,将显示每个缺少的SendPixelEnd
编辑:EV3Messaging.SendMessages通过前几行中添加的蓝牙发送消息:
static List<byte> btMessage = new List<byte>();
static public async Task SendMessages()
{
if (_socket != null)
await _socket.OutputStream.WriteAsync(btMessage.ToArray(), 0, btMessage.Count);
}
为什么会发生这种情况?我该如何解决
提前谢谢
PS:抱歉我的英语不好^ ^问题解决:每次发送数据时,我都忘记清除btMessage列表,这导致了这种奇怪的行为。此问题也可能是因为从蓝牙设备接收数据的方式不正确 然后SendMessages方法变为:
static public async Task SendMessages()
{
if (_socket != null)
await _socket.OutputStream.WriteAsync(btMessage.ToArray(), 0, btMessage.Count);
btMessage.Clear();
}
因为每次我添加消息时,新帧都会添加到消息列表的末尾
此外,为了获取传入消息,我使用以下代码:
public static void InputMessagesManager(Action<BtMessage> incomingMessageEvent)
{
_tokenSource = new CancellationTokenSource();
Task t = Task.Factory.StartNew(async () =>
{
Stream inputStream = _socket.InputStream;
while (!_tokenSource.IsCancellationRequested)
{
if (inputStream == null)
inputStream = _socket.InputStream;
if (inputStream != null && inputStream.CanRead)
{
await inputStream.ReadAsync(_sizeBuffer, 0, _sizeBuffer.Length);
short size = (short)(_sizeBuffer[0] | _sizeBuffer[1] << 8);
if (size != 0)
{
byte[] frame = new byte[size];
await inputStream.ReadAsync(frame, 0, frame.Length);
BtMessage btMes = new BtMessage(frame);
incomingMessageEvent(btMes);
Console.WriteLine("Received: " + btMes.name + " -> " + btMes.getValueAsNumber());
}
}
}
}, _tokenSource2.Token, TaskCreationOptions.LongRunning, TaskScheduler.Current);
}
如果没有Ev3Messaging.SendMessages上的代码,则无法确定原因。哦,抱歉,我将添加它。看来蓝牙流不起作用,当您关闭应用程序时,由于套接字已关闭,所有操作都将结束。您是否在连接的设备上接收到消息?只接收到其中一些消息,我刚刚意识到一些SendPixelEnd显示在SendPixels之间,当然与接收到的消息相关。。。。当活动关闭而不是应用程序关闭时,蓝牙设备会接收所有发送的消息。尽量不要使用InputStream和OutputStream属性,只检索一次,并在任何地方使用检索到的实例,你不知道这些属性在引擎盖下做什么,每次调用它们时,它们可能会构造一个新的流。另外,在连接关闭之前,不要使用计时器读取、创建线程或任务并持续读取。从输入流读取不应干扰输出流。