Android Question It is possible to wait for a B4XPages page to disappear? {Solved]

[carlos7000]

Hello, I would like to know if it is possible to wait for a B4XPages (QrCode Reader) page to finish and then obtain the result.

The first thing I do is load the page that reads in qrcode

Private Sub ButtonQrOrigen_Click
    B4XPages.ShowPage("Qr Code Reader")
    Dim Resultado As String = QRC_Reader.Resultado
    Log($"Resultado ${Resultado}"$)
End Sub

As we know, all the code of the function is executed without waiting for the result

When the reader captures the text and the FoundBarcode function is executed, the page closes with the line B4XPages.ClosePage(Me)

Private Sub FoundBarcode (msg As String)
    lblResult.Text = msg
    toast.Show($"Found [Color=Blue][b][plain]${msg}[/plain][/b][/Color]"$)
    B4XPages.ClosePage(Me)
End Sub

As the title says, is it possible to wait for the page Disappear, unload, etc or not?

I need to show the qr code reader several times. Is it possible to do it as a Wait? If not, how else do you suggest I do it?

 

[epiCode]

You can put the code in:

Private Sub B4XPages_Disappear
    
End Sub

 

[LucaMs]

'In page x

Private Sub Button1_Click
    pagOne.CallingPage = Me
    pagOne.CallingPageEvent = "SomeName"
    B4XPages.ShowPage("pagOne")
    Wait For SomeName
    Log("Completed")
End Sub

'In "pagOne" - your "scanning page"

Sub Class_Globals
    Private Root As B4XView 'ignore
    Private xui As XUI 'ignore
   
    Public CallingPage As Object
    Public CallingPageEvent As String
End Sub


Private Sub B4XPage_Disappear
    CallSubDelayed(CallingPage, CallingPageEvent)
End Sub

 

[toby]

The code below keeps the page open until the user taps "Close the page" button. This is what you want if I understand you correctly. You need to define dialog in the class_Globals

dim dialog as b4xDialog

At the end of B4xPage_Create, add:

Private Sub B4XPage_Created (Root1 As B4XView)
'....
    dialog.initialize(root)
End Sub

Private Sub FoundBarcode (msg As String)
    lblResult.Text = msg
    
    Wait For (dialog.Show($"Found [Color=Blue][b][plain]${msg}[/plain][/b][/Color]"$,  "OK", "", "Close the page"))complete(intResult As Int)
    If intResult=xui.DialogResponse_Cancel Then
        B4XPages.ClosePage(Me)
    End If
End Sub

 

[carlos7000]

'In page x

Private Sub Button1_Click
    pagOne.CallingPage = Me
    pagOne.CallingPageEvent = "SomeName"
    B4XPages.ShowPage("pagOne")
    Wait For SomeName
    Log("Completed")
End Sub

'In "pagOne" - your "scanning page"

Sub Class_Globals
    Private Root As B4XView 'ignore
    Private xui As XUI 'ignore
  
    Public CallingPage As Object
    Public CallingPageEvent As String
End Sub


Private Sub B4XPage_Disappear
    CallSubDelayed(CallingPage, CallingPageEvent)
End Sub

The code worked very well.

Thank you so much.

The following code confuses me.

Private Sub B4XPage_Disappear
    CallSubDelayed(CallingPage, CallingPageEvent)
End Sub

How can you call the event someName. It seems to me that someName does not exist.

Please explain me the code

 

[carlos7000]

The code below keeps the page open until the user taps "Close the page" button. This is what you want if I understand you correctly. You need to define dialog in the class_Globals

dim dialog as b4xDialog

At the end of B4xPage_Create, add:

Private Sub B4XPage_Created (Root1 As B4XView)
'....
    dialog.initialize(root)
End Sub

Private Sub FoundBarcode (msg As String)
    lblResult.Text = msg
   
    Wait For (dialog.Show($"Found [Color=Blue][b][plain]${msg}[/plain][/b][/Color]"$,  "OK", "", "Close the page"))complete(intResult As Int)
    If intResult=xui.DialogResponse_Cancel Then
        B4XPages.ClosePage(Me)
    End If
End Sub

I have not tested your code.

I will do it later.

Thank you all very much, especially LucaMs

He left you a video of how the test program was working.

 

[LucaMs]

How can you call the event someName. It seems to me that someName does not exist.

You have surely seen:

Wait For SomeName

It was strange to me too but it is evidently a possible technique related to Resumables.

 

[carlos7000]

You have surely seen:

Wait For SomeName

It was strange to me too but it is evidently a possible technique related to Resumables.

Thank you very much for your answer