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Although VB2010 is generally a
programming language designed for creating business and other
industrial applications and not for creating animation, it can be
used to create animation. In this lesson, we will show you
just that.
28.1 Moving an
object
In this section, we will show you how
to move an object by pressing a command button. You need to make use
of the Top and Left properties of an object to create animation. The
Top property defines the distance of the object from the top most
border of the screen while the Left property defines the distance of
the object from leftmost border of the screen. By adding or
subtracting the distance of the object we can create the animated
effect of moving an object.
Start a new project and name it as
Movable Object, or any name you wish. Now insert a PictureBox and in
its Image property import a picture from your hard drive or other
sources. Next, insert four command buttons, change their captions to
Move Up, Move Down, Move Left and Move Right. Name them as
MoveUpBtn, MoveDowbBtn, MoveLeftBtn and MoveRightBtn.
Now, click on the buttons and key in
the following code:
Private
Sub MoveDownBtn_Click(ByVal sender As
System.Object,
ByVal e As
System.EventArgs)
Handles MoveDownBtn.Click
PictureBox1.Top = PictureBox1.Top +
10
End
Sub
Private
Sub MoveLeftBtn_Click(ByVal sender As
System.Object,
ByVal e As
System.EventArgs)
Handles MoveLeftBtn.Click
PictureBox1.Left = PictureBox1.Left -
10
End
Sub
Private
Sub MoveRightBtn_Click(ByVal sender As
System.Object,
ByVal e As
System.EventArgs)
Handles MoveRightBtn.Click
PictureBox1.Left = PictureBox1.Left +
10
End
Sub
Explanation:
Each time the user clicks on the Move
Down button, the distance of the PictureBox increases by 10 pixels
from the top border, creating a downward motion. On the other hand,
each time the user clicks on the
Move Up button, the distance of the PictureBox decreases by 10
pixels from the top borders, thus creating an upward motion. In
addition, each time the user
clicks on the Move Left button, the distance of the PictureBox
decreases by 10 pixels from the left border, thus creating a
leftward motion. Lastly, each
time the user clicks on the Move Right button, the distance of
the PictureBox increases by 10 pixels from the left
border, thus creating an rightward
motion.
The interface is shown
below:
28.2 Creating Animation using
Timer
We can create continuous animation
using timer without the need to manually clicking a command button.
We can create left to right or top to bottom motion by writing the
necessary code.
First of all, insert a PictureBox into
the form. In the PictureBox properties window,select the image
property and click to import an image file from your external
sources such as your hard drive, your Pendrive or DVD. We have
inserted an image of a bunch of grapes.Next, insert a Timer control
into the form set its interval property to 100, which is
equivalent to 0.1 second. Finally, add two command button to the
form, name one of them as AnimateBtn and the other
one as StopBtn, and change to caption to Animate
and Stop respectively.
We make use of the Left
property of the PictureBox to create the motion.
PictureBox.Left means the distance of the
PictureBox from the left border of the Form . Now click on the
Timer control and type in the following
code:
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
Timer1.Tick
If
PictureBox1.Left < Me.Width
Then
PictureBox1.Left = PictureBox1.Left
+ 10
Else
PictureBox1.Left = 0
End If
End Sub
In the code above, Me.Width represents
the width of the Form. If the distance of the PictureBox from the
left is less than the width of the Form, a value of 10 is added to
the distance of the PictureBox from the left border each time
the Timer tick, or every 0.1 second in this example. When the
distance of the PictureBox from the left border is equal to the
width of the form, the distance from the left border is set to 0,
which move the PictureBox object to the left border and then move
left again, thus creates an oscillating motion from left to right.
We need to insert a button to stop motion. The code
is:
Timer1.Enabled =
False
To animate
the PictureBox object, we insert a command button and key in the
following code:
Timer1.Enabled = True
The Interface of the Animation
program
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