VB.net - Openfilepicker does not work in windows mobile 10 app

Question

I'm developing a Windows 10 UWP and this piece of code :

Dim wopk As FileOpenPicker = New FileOpenPicker
With wopk
 .ViewMode = PickerViewMode.List
 .SuggestedStartLocation = PickerLocationId.DocumentsLibrary
 .FileTypeFilter.Add(".txt")
 dim wfile = Await .PickSingleFileAsync()
End with

crash on my Lumia 535 (Windows mobile 10) without error message (both debug and runtime mode).

Appears the splash screen and still hang.

On desktop everything works fine.

In package manifest Declarations, I defined for File Open/Save Picker the ".txt" extension.

The project has as target "Windows 10" and as version "Build 10586".

Answer 1

here is something that i have quickly written up, it should allow you to access openfilepicker
It's not complete, however it should lead you in the right direction.

Imports Windows.Storage.Pickers
Public NotInheritable Class MainPage
Inherits Page

Private Async Sub button_Click(sender As Object, e As RoutedEventArgs) Handles button.Click
    Dim openfilepicker = New FileOpenPicker
    openfilepicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary
    openfilepicker.FileTypeFilter.Add(".txt")
    openfilepicker.CommitButtonText = "Open"

    Dim Textfile = Await openfilepicker.PickSingleFileAsync()
    If Textfile IsNot Nothing Then
        Dim SelectedTextFile = Await Textfile.OpenAsync(Windows.Storage.FileAccessMode.ReadWrite)
        'Write your code here using SelectedTextFile as the source for the async.
    End If

End Sub
End Class

If you have any problems i will do my best to help you out, however from what your question has stated, this should be more than enough.
Happy Coding!