App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 352 · 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.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Sports", "Music", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Sports (d) Music
2. 2.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) your last game level (d) a shared to-do list
3. 3.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
4. 4.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the app is closed (d) the phone is lost
5. 5.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) skip the internet (d) shrink the app
6. 6.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Hindi", "Art", "Science"];
   show(notes[0]); (a) Science (b) Hindi (c) Art
8. 8.💾 What number does this code show?
   let points = 3;
   points = points - 3;
   points = points + 3;
   show(points);
9. 9.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
10. 10.True or false: photos on two devices fits saving on the phone. (a) True (b) False
11. 11.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
12. 12.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) notes to read offline (d) the sound on/off setting
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Monsoon (c) Stars
14. 14.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Art", "Maths"];
    show(notes[0]); (a) Sports (b) Science (c) Art (d) Maths
15. 15.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) the sound on/off setting (d) photos on two devices
17. 17.💾 What number does this code show?
    let friends = ["Kabir", "Arjun", "Riya", "Aman"];
    friends.push("Meera");
    friends.push("Zoya");
    show(friends.length);
18. 18.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
19. 19.True or false: your last game level fits saving in the cloud. (a) False (b) True
20. 20.💾 What number does this code show?
    let notes = ["Art", "Sports", "Science", "Hindi"];
    notes.push("Maths");
    show(notes.length);
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Monsoon", "Ocean", "Sunrise"];
    show(songs[1]); (a) Ocean (b) Rain (c) Monsoon (d) Kites
22. 22.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Monsoon", "Stars"];
    songs.push("Rain");
    show(songs.length);
23. 23.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Science (c) Music (d) Hindi
24. 24.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 2 (d) 1
25. 25.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a class leaderboard (d) a draft you are typing
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Riya"];
    show(friends[0]); (a) Meera (b) Riya (c) Aman
27. 27.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Kites", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Monsoon (c) Stars (d) Sunrise
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Music", "Science", "Maths"];
    show(notes[1]); (a) Hindi (b) Science (c) Maths (d) Music
29. 29.💾 What number does this code show?
    let stars = 6;
    stars = stars - 5;
    stars = stars + 5;
    show(stars);
30. 30.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Sunrise"];
    show(songs[0]); (a) Ocean (b) Kites (c) Sunrise
31. 31.Which of these fits saving on the phone? (a) a shared to-do list (b) a draft you are typing (c) a class leaderboard (d) chat messages to friends
32. 32.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Zoya", "Arjun", "Riya", "Kabir"];
    show(friends[2]); (a) Riya (b) Zoya (c) Aman (d) Arjun
33. 33.💾 What number does this code show?
    let friends = ["Kabir", "Zoya"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
34. 34.True or false: notes to read offline fits saving on the phone. (a) False (b) True
35. 35.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);
36. 36.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) notes to read offline (d) photos on two devices
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Rain
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Hindi
39. 39.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
40. 40.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students