-ORIENTED

UNDERSTAND OBJECT-ORIENTED PROGRAMMING
Feature
>STEP-05
Compare scores
We’ve only got one sprite so far. But we’re about to
add another and compare one sprite’s total with the
other. Choose the Sensing selection of blocks and
look for one marked x-position of e. Change
‘x-position’ to total. Drag the block into the correct
side of the greater-than block.
>STEP-03
Throw the dice
Click on Events and drag a when green clicked
block to the scripts area. Below this you need to
add three set diceN to pick nd 1 to 6 blocks.
Below these blocks, add set to dice1 + dice2
+ dice3 (you need to drag one () + () block inside
another to add up three blocks.
>STEP-04
Speak
Now drag a for block and attach it to the end of
the code. Change it to for 1 secs. Below
that, drag an if block. Inside, add a [] > [] (greaterthan)
block. Drag the variable to the left side of
the greater-than block. Drag a block inside the if
block and change ‘Hello!’ to ‘I win!’.
>STEP-06
Player 2
Our Player 1 is ready. Now we’re going to clone the sprite
to create a Player 2. Right-click the sprite and choose
Duplicate. The new cat sprite will be automatically called
‘Player2’. Click on Player1 in the Sprites window. Change
the of e block to of e (as shown
below). Now Player1 compares their total to Player2 (and
Player2 is comparing theirs to Player1). Click the green
g to run the progrm nd ee whih pyer win.
SCOPE
he concet of coe i imortant in oectoriente rogramming n Scratch, it
o imle that o ma not een notice it t or to laer each hae their on
dice1, dice2, an dice3 ariale, l a total ariale hee ariale are local in
coe hen Plaer annonce total, it their total f oth rite accee the
ame total, it ol e gloal in coe ariale in oect are local in coe
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