Windows Phone應用程序狀態和攝像頭

Question

好的，所以我正在使用以下代碼在我的應用中顯示相機，效果很好！ 問題是當我導航離開並使用后堆棧返回應用程序時，直到我手動調用代碼后，相機才會顯示。

我如何使其自動顯示？

預先感謝Youuu

Dim cam As New Microsoft.Devices.PhotoCamera()

Public Sub New()
    InitializeComponent()
    SupportedOrientations = SupportedPageOrientation.Portrait
End Sub

Private Sub opening() Handles Me.Loaded
    cam = New Microsoft.Devices.PhotoCamera()
    viewfinderBrush.RelativeTransform = New CompositeTransform() With {.CenterX = 0.5, .CenterY = 0.5, .Rotation = 90}
    viewfinderBrush.SetSource(cam)
End Sub


Private Sub Closing() Handles Me.Unloaded
    cam.Dispose()


End Sub

Answer 1

修復了我自己的問題，僅使用了受保護的覆蓋物:)

像這樣

Protected Overrides Sub OnNavigatedTo(e As NavigationEventArgs)
    MyBase.OnNavigatedTo(e)
    cam = New Microsoft.Devices.PhotoCamera()
    viewfinderBrush.RelativeTransform = New CompositeTransform() With {.CenterX = 0.5, .CenterY = 0.5, .Rotation = 90}
    viewfinderBrush.SetSource(cam)
End Sub

Protected Overrides Sub OnNavigatedFrom(e As NavigationEventArgs)
    MyBase.OnNavigatedFrom(e)

    If cam IsNot Nothing Then
        cam.Dispose()
        cam = Nothing
    End If
End Sub