Page 98 - Learn To Program With Scratch

3. Detach the script connected to the when I receive DrawFlower
block and connect it to the define DrawFlower block, as shown in
Figure 4-12. This results in a new procedure, called DrawFlower,
that is implemented as a custom block. Delete the when I receive
DrawFlower block because it is no longer needed.

This script was originally connected
to the

block. Detach it and connect it to
the define DrawFlower block as
shown here.

Figure 4-12: The DrawFlower procedure implemented as a custom block

4. Now that we’ve created a DrawFlower procedure, we just need to call
it from the Draw message handler. Modify the Draw message handler
as shown in Figure 4-13. Note that we only replaced the broadcast
DrawFlower and wait block with our new DrawFlower custom block.

Replace the

block in the original script with the new
custom block.

Figure 4-13: Calling DrawFlower from the Draw message handler

The program is now complete, and you can test it. Click the mouse on
the Stage to verify that the program still works as before. See “Running
Without Screen Refresh” on page 77 to learn how you can speed up the
execution of this program.
Now that you know the basics behind custom blocks, you can take them
a step further by making blocks that can accept inputs.

76 Chapter 4
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