Android Question Array print numbers from array

[ronovar]

I have items in array

Dim Items() As Int = Array As Int (1, 2, 3, 4)

I need to get from array this:

1st Call:
4 1 2

2st Call:
1 2 3

3st Call:
2 3 4

4st Call:
3 4 1

5st Call:
4 1 2

So as you can see it start with LAST_ITEM | FIRST_ITEM | SECOND_ITEM

And then incrementing each of three items by one.

This i need for horizontal scroller when i press LEFT Button....When i press RIGHT button it needs to get inverse...

I search forum but could not find function for sort array like i need. I can make it manuall but i like it to calculate thease numbers in example automatically.

 

[ronovar]

I get this code that works as expected but could be short and more faster?

'GET - KeyPressed
Sub Activity_KeyPress(KeyCode As Int) As Boolean   
    'SELECT - Remote Code
    Select KeyCode
        Case KeyCodes.KEYCODE_DPAD_LEFT
            'CHECK - Scrolled
            If (Scrolled = 0 Or Scrolled = Items.Length) Then
                Log(Items(Items.Length-1))
                Log(Items(0))
                Log(Items(1))
                Scrolled = 1
            Else
                Log(Items(Scrolled-1))
                Log(Items(Scrolled))
               
                If (Scrolled = Items.Length-1) Then
                    Log(Items(0))
                Else
                    Log(Items(Scrolled+1))
                End If
               
                Scrolled = Scrolled + 1
            End If       
    End Select
End Sub

 

[klaus]

Something like this:

Private Items() As Int = Array As Int (1, 2, 3, 4, 5)
Private Scrolled = 2 As Int
Private ItemsToDisplay = 3 As Int

Private i, j As Int

Scrolled = Scrolled + 1
If Scrolled = Items.Length Then
    Scrolled = 0
End If

j = Scrolled
For i = 0 To ItemsToDisplay - 1
    Log(Items(j))
    j = j + 1
    If j = Items.Length Then
        j = 0
    End If
Next

 

[DonManfred]

If you want to get all permutations of a given string then you can use this library

https://www.b4x.com/android/forum/t...t-all-permutations-of-a-string.61084/#content

    Dim l As List = perm.permute("12345")
    For i = 0 To l.Size -1
        Log(l.Get(i))
    Next

LogCat connected to: 9885e6514556383552
--------- beginning of main
--------- beginning of system
** Service (starter) Create **
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
21435
21453
52143
25143
21543
42153
42135
54213
42513
45213
21354
25134
21345
52134
21534
24153
24135
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52413
24513
25341
23415
23451
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52341
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42315
54231
45231
25431
24351
24315
52431
24531
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52314
23154
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34251
34215
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45321
54321
43215
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53241
32451
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32415
12435
15243
51243
12453
12543
12345
12354
15234
12534
51234
54123
45123
41235
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41523
51423
14253
15423
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31452
53142
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35142
31425
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34152
34512
53412
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31254
31524
35124
53124
31245
43125
43512
45312
43152
54312
14325
15432
51432
14532
14352
41325
45132
54132
41352
41532
13254
51324
13245
13524
15324
51342
13452
13542
15342
13425
** Activity (main) Resume **

 

[ronovar]

Something like this:

Private Items() As Int = Array As Int (1, 2, 3, 4, 5)
Private Scrolled = 2 As Int
Private ItemsToDisplay = 3 As Int

Private i, j As Int

Scrolled = Scrolled + 1
If Scrolled = Items.Length Then
    Scrolled = 0
End If

j = Scrolled
For i = 0 To ItemsToDisplay - 1
    Log(Items(j))
    j = j + 1
    If j = Items.Length Then
        j = 0
    End If
Next

Thanks this fors as expected is short code and really fast...could you update it to get rewerse way too?

I have LEFT and RIGHT buttons so when i press RIGHT button i get this what you write excellent code...now i need to get hen i press LEFTbutton to go back throught array.

I try to change - where is + but i got error..stil traying to archive in minus way.

 

[JordiCP]

Just to save some lines on Klaus answer...

Private i, j As Int

Scrolled = (Scrolled + 1) Mod Items.Length

j = Scrolled
For i = 0 To ItemsToDisplay - 1
  Log(Items(j))
  j = (j + 1) Mod Items.Length
Next

 

[ronovar]

Just to save some lines on Klaus answer...

Private i, j As Int

Scrolled = (Scrolled + 1) Mod Items.Length

j = Scrolled
For i = 0 To ItemsToDisplay - 1
  Log(Items(j))
  j = (j + 1) Mod Items.Length
Next

this is shortest and very quck function..thanks....you get
Scrolled + 1 could you write
Scrolled - 1 to get one items back from array? Now it gets one items nex from array

 

[JordiCP]

For LEFT button change the line

Scrolled = (Scrolled + Items.Length - 1) Mod Items.Length

 

[ronovar]

Thanks works as expected....really fast and short code...big like