Android Question AnotherDatePicker (B4X) error r/w to a Map

[LucaMs]

I'm using a Map to save a date (long) selected with AnotherDatePicker.

When I read the map I get "strange" error (set a breakpoint on line 67 - Dim lngDate...).

 

[DonManfred]

Sub Read
    Log("Reading")
    If File.Exists(File.DirInternal, DATES_FILENAME) Then
        mmapDates = File.ReadMap(File.DirInternal, DATES_FILENAME)
        Log(mmapDates)
        For Each key As String In mmapDates.Keys
            If key = DATES_FIRST_KEY Then
                Dim lngDate As Long = mmapDates.Get(key)
                AnotherDatePicker1.Date = lngDate
            End If
        Next
    End If
End Sub

 

[LucaMs]

Why? Map.Get does not work anymore?

 

[DonManfred]

As you can see in my code map.Get does work if you use the right Key

 

[DonManfred]

i suggest to use String as KEytype

in this case

    Private Const DATES_FIRST_KEY As String = "1"

does work without the loop over all keys

Sub Read
    Log("Reading")
    If File.Exists(File.DirInternal, DATES_FILENAME) Then
        mmapDates = File.ReadMap(File.DirInternal, DATES_FILENAME)
        Log(mmapDates)
        'For Each key As String In mmapDates.Keys
        '    If key = DATES_FIRST_KEY Then
        Dim lngDate As Long = mmapDates.Get(DATES_FIRST_KEY)
                AnotherDatePicker1.Date = lngDate
            'End If
        'Next
    End If
End Sub

 

[LucaMs]

As you can see in my code map.Get does work if you use the right Key

I have not tried but I trust.
Anyway, you can see that the key I used is a constant of type Int.

 

[LucaMs]

i suggest to use String as KEytype

Ok, but still there is something strange, since as key you can use any type of object.

https://www.b4x.com/android/forum/threads/timer-in-an-array-linked-sub.89538/#post-566386

 

[LucaMs]

Ok, but still there is something strange, since as key you can use any type of object.

https://www.b4x.com/android/forum/threads/timer-in-an-array-linked-sub.89538/#post-566386

Erel's used timers as key in CallSubPlus.

--------------------------------------

 

[DonManfred]

Ok, but still there is something strange, since as key you can use any type of object.

Yes. But as you are using File.WriteMap all Values are converted to Strings! So after File.ReadMap all Keys are Strings. You then try to access the Key using an Int and this leads into a null because the Key does not exists.

https://www.b4x.com/android/forum/pages/results/?query=File.WriteMap

The solution is to use KVS or raf.WriteB4XObject.

 

[LucaMs]

The solution is to use KVS or raf.WriteB4XObject.

This was my first idea; then I thought: "Why use KVS since you can save maps?"

Thank you.

 

[DonManfred]

Why use KVS since you can save maps?

If you do it right then it does work. Use RandomAccessFiles WriteB4XObject/ReadB4XObject

 

[LucaMs]

If you do it right then it does work. Use RandomAccessFiles WriteB4XObject/ReadB4XObject

Yes but I wanted to use an easy, quick way and with few libraries, since I don't think to complete this app.

Initially I was thinking to save a simple string!

 

[LucaMs]

Ehm... sorry (I'm very "tired": https://www.b4x.com/android/forum/threads/when-you-feel-a-bit-down.92029/)
and I forgot that I had already solved using strings as keys.

The next problem was different (and I will open a new thread, probably), related to AnotherDatePicker (it seems to not allow dates before 1970 and... I was born before )