
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games.   The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user.   This task demonstrates this.



Task

Create a window containing the string "Hello World! " (the trailing space is significant).

Make the text appear to be rotating right by periodically removing one letter from the end of the string and attaching it to the front.

When the user clicks on the (windowed) text, it should reverse its direction.




VERSION 5.00
Begin VB.Form Form1
   Begin VB.Timer Timer1
      Interval = 250
   End
   Begin VB.Label Label1
      AutoSize = -1  'True
      Caption  = "Hello World! "
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
'Everything above this line is hidden when in the IDE.

Private goRight As Boolean
 
Private Sub Label1_Click()
    goRight = Not goRight
End Sub
 
Private Sub Timer1_Timer()
    If goRight Then
        x = Mid(Label1.Caption, 2) & Left(Label1.Caption, 1)
    Else
        x = Right(Label1.Caption, 1) & Left(Label1.Caption, Len(Label1.Caption) - 1)
    End If
    Label1.Caption = x
End Sub