C# WindowsPhone PhoneCamera-页面恢复时出现异常
我有一个奇怪的例外。我在一个页面中使用PhoneCamera API,用户可以制作一些phothos,在捕获后直接上传 我的代码:C# WindowsPhone PhoneCamera-页面恢复时出现异常,c#,windows-phone-8,camera,aggregateexception,C#,Windows Phone 8,Camera,Aggregateexception,我有一个奇怪的例外。我在一个页面中使用PhoneCamera API,用户可以制作一些phothos,在捕获后直接上传 我的代码: protected override void OnNavigatedTo(NavigationEventArgs e) { base.OnNavigatedTo(e); _mediaLibrary = new MediaLibrary(); // Initialize the camera object _phoneCamera
protected override void OnNavigatedTo(NavigationEventArgs e)
{
base.OnNavigatedTo(e);
_mediaLibrary = new MediaLibrary();
// Initialize the camera object
_phoneCamera = new PhotoCamera(CameraType.Primary);
_phoneCamera.Initialized += CamInitialized;
_phoneCamera.AutoFocusCompleted += PhoneCamera_AutoFocusCompleted;
_phoneCamera.CaptureImageAvailable += PhoneCamera_CaptureImageAvailable;
// Display the camera feed in the UI
ViewfinderBrush.SetSource(_phoneCamera);
// Rotation for transform
ViewfinderTransform.Rotation = _phoneCamera.Orientation;
}
protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
if (_phoneCamera != null)
{
// Cleanup
_phoneCamera.Dispose();
_phoneCamera.Initialized -= CamInitialized;
_phoneCamera.AutoFocusCompleted -= PhoneCamera_AutoFocusCompleted;
_phoneCamera.CaptureImageAvailable -= PhoneCamera_CaptureImageAvailable;
if (_cameraInizialized)
{
CameraButtons.ShutterKeyHalfPressed -= CameraButtons_ShutterKeyHalfPressed;
CameraButtons.ShutterKeyPressed -= CameraButtons_ShutterKeyPressed;
}
}
base.OnNavigatingFrom(e);
}
private void CamInitialized(object sender, CameraOperationCompletedEventArgs e)
{
if (e.Succeeded)
{
// Set flashmode
Dispatcher.BeginInvoke(() => { _phoneCamera.FlashMode = FlashMode.Auto; });
// Subscribe to hardeware-button-events
CameraButtons.ShutterKeyHalfPressed += CameraButtons_ShutterKeyHalfPressed;
CameraButtons.ShutterKeyPressed += CameraButtons_ShutterKeyPressed;
_cameraInizialized = true;
}
else
{
// Show error message
}
}
触发初始化事件后,一切正常。但我得到了一个例外,当用户点击手机的主页按钮,而相机正在初始化。(未触发初始化事件)
当用户使用“后退”按钮返回时,会发生以下异常:
[Type]:[AggregateException]
[ExceptionMessage]:[One or more errors occurred.]
[StackTrace]:[
at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at Microsoft.Devices.Camera.OpenCaptureDevice()
at Microsoft.Devices.Camera.<>c__DisplayClass2.<InitializeVideoSession>b__0()]
[InnerExceptions]:[[[Type]:[InvalidOperationException]
[Message]:[The text associated with this error code could not be found.
Unable to acquire the camera. You can only use this class while in the foreground.]
[Type]:[AggregateException]
[例外消息]:[发生了一个或多个错误。]
[StackTrace]:[
位于System.Threading.Tasks.Task.ThrowifeException(布尔值IncludeTaskCanceledException)
在System.Threading.Tasks.Task.Wait(Int32毫秒计时,CancellationToken CancellationToken)
在Microsoft.Devices.Camera.OpenCaptureDevice()上
在Microsoft.Devices.Camera.c__DisplayClass2.b__0()中]
[InnerExceptions]:[[[Type]:[InvalidOperationException]
[消息]:[找不到与此错误代码关联的文本。
无法获取相机。您只能在前台使用此类。]
我尝试过很多其他的选择,但都没有效果。我现在不知道为什么会发生这个错误。虽然我知道它发生在哪里,在什么情况下
欢迎提供任何帮助。谢谢。PhoneCamera中存在已知的应用程序崩溃错误。当应用程序未初始化时,从camera页面返回时,应用程序将崩溃。您可以参考