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Basic (Sprite) Animation

To move an object we have to manipulate its x, y coordinates on the form the object belongs to. A key element in this process is the "Timer" control!

Consider the following scenario: A balloon rises up to a predefined position then start to move across the form.

Form layout and controls are shown below:

Control Objects Required:

Control Properties:

Typical Code:

Private Sub CmdStart_Click()
    'Start Timer
    Timer1.Enabled = True
End Sub

Private Sub CmdStop_Click()
    'Stop Timer
    Timer1.Enabled = False
End Sub

Private Sub Timer1_Timer()
    'if balloon reaches predefined height start to move
    'horizontally at constant height
    If ImgBalloon.Top < 200 Then
        'move balloon left  15 is an arbitrary value
        ImgBalloon.Left = ImgBalloon.Left + 15

        'rewind balloon position to left of form
        If ImgBalloon.Left > Me.Width Then
            ImgBalloon.Left = 0
        End If
    Else
        'increment balloon height  10 is an arbitrary value
        ImgBalloon.Top = ImgBalloon.Top - 10
    End If
End Sub