Notes:
Finally, complete your script with a “wait [ ] secs” block and “stop all” block from Control. Set the value of the “wait [ ] secs” to “4” and place both blocks at the very end of your script, outside both “if/else” blocks.
A
A The cat has chosen A.
So A is stored in the variable “country”.
country
country
The destination the dog chooses will be stored in the variable “country”. This is important, because this variable will be used by the script for the stage to determine the script’s output.
The script for the stage
To complete the program we need to program the backgrounds. If you haven’t imported them from RPiScratch\Resources\Backgrounds, now’s the time to do it.
Tip...
Users do not always do what they are
supposed to do. If a user provides an unexpected input, this can cause an “error” in the program, which will often cause the program to “crash”. Programs that have errors in them are said to contain “bugs”. An important task for a programmer is testing their program to make sure it is bug-free.
Select the stage in the Sprites List and build the script you can see in the screenshot above.
Here, we have created three “nested if” conditional statements, which will switch the background according to the dog’s choice. We use the term “ nested ” when one conditional statement is put inside another one. Each time we use this program, the stage has to be reset to the “ brick-wall1 ” background. The conditional statements need to keep checking until the dog has made her choice, so I have put them in a “forever loop”.
A beginner’s guide to Scratch
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