App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 644 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
2. 2.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
3. 3.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Maths", "Hindi", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Hindi (c) Sports (d) Music
4. 4.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) your last game level
5. 5.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the phone is lost (d) the app is closed
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Sunrise", "Ocean", "Rain", "Kites"];
   show(songs[3]); (a) Kites (b) Ocean (c) Rain (d) Sunrise
8. 8.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
9. 9.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) a shared to-do list (d) a draft you are typing
10. 10.💾 What number does this code show?
    let lives = 5;
    lives = lives - 4;
    lives = lives + 1;
    show(lives);
11. 11.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) chat messages to friends (d) notes to read offline
12. 12.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean", "Sunrise"];
    songs.push("Stars");
    show(songs.length);
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Stars (c) Ocean
14. 14.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) photos on two devices
15. 15.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) use it on any device (d) skip the internet
16. 16.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Stars"];
    show(songs[0]); (a) Stars (b) Rain (c) Monsoon
17. 17.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
18. 18.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Science", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Music (d) Science
20. 20.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) a class leaderboard (d) a draft you are typing
21. 21.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Ocean", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Rain (d) Stars
24. 24.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
25. 25.Which of these fits saving in the cloud? (a) a draft you are typing (b) a class leaderboard (c) notes to read offline (d) the sound on/off setting
26. 26.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 What number does this code show?
    let notes = ["Maths", "Hindi"];
    notes.push("Art");
    show(notes.length);
28. 28.💾 What number does this code show?
    let friends = ["Kabir", "Zoya", "Aman"];
    friends.push("Riya");
    show(friends.length);
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Art", "Maths", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Art (c) Science (d) Maths
30. 30.💾 What number does this code show?
    let score = 8;
    score = score - 7;
    score = score + 2;
    show(score);
31. 31.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
32. 32.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.True or false: your last game level fits saving on the phone. (a) False (b) True
34. 34.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a cloud backup (d) a shared chat
35. 35.💾 What number does this code show?
    let coins = 8;
    coins = coins - 7;
    coins = coins + 2;
    show(coins);
36. 36.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
37. 37.💾 Which can hold many values in order? (a) a switch (b) a button (c) a list (d) a single number
38. 38.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
39. 39.Which of these fits saving on the phone? (a) the sound on/off setting (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
40. 40.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 2 (d) 10

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