← Data: variables, lists and saving lesson New set →

App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 102 · 40 questions
TalentJR

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.

NameDateTime takenScore ___ / 40
  1. 1.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a shared to-do list (d) a class leaderboard
  2. 2.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
  3. 3.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) a shared to-do list (d) your last game level
  4. 4.💾 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
  5. 5.True or false: photos on two devices fits saving on the phone. (a) False (b) True
  6. 6.💾 What number does this code show?
    let score = 8;
    score = score - 6;
    score = score + 1;
    show(score);
  7. 7.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Hindi", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Maths (b) Hindi (c) Art (d) Music
  8. 8.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 4;
    show(points);
  9. 9.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
  10. 10.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
  11. 11.💾 Which can hold many values in order? (a) a button (b) a list (c) a switch (d) a single number
  12. 12.💾 What number does this code show?
    let notes = ["Sports", "Music", "Art"];
    notes.push("Maths");
    show(notes.length);
  13. 13.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Arjun", "Zoya"];
    show(friends[2]);     (a) Riya (b) Zoya (c) Arjun (d) Kabir
  14. 14.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Meera", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Riya (b) Aman (c) Meera (d) Kabir
  15. 15.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
  16. 16.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Stars", "Ocean", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Monsoon (b) Sunrise (c) Stars (d) Ocean
  17. 17.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) a class leaderboard (d) a shared to-do list
  18. 18.💾 What number does this code show?
    let friends = ["Arjun", "Kabir", "Zoya", "Meera"];
    friends.push("Aman");
    friends.push("Riya");
    show(friends.length);
  19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Hindi", "Art"];
    show(notes[1]);     (a) Art (b) Music (c) Hindi (d) Sports
  20. 20.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) your last game level (d) a class leaderboard
  21. 21.💾 What number does this code show?
    let score = 8;
    score = score - 5;
    score = score + 2;
    show(score);
  22. 22.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
  23. 23.💾 What number does this code show?
    let notes = ["Sports", "Hindi", "Music"];
    notes.push("Art");
    show(notes.length);
  24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Hindi", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Maths (b) Hindi (c) Science (d) Music
  25. 25.💾 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
  26. 26.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
  27. 27.💾 What number does this code show?
    let stars = 9;
    stars = stars - 5;
    stars = stars + 5;
    show(stars);
  28. 28.True or false: your last game level fits saving on the phone. (a) False (b) True
  29. 29.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
  30. 30.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Monsoon", "Rain", "Kites"];
    show(songs[0]);     (a) Stars (b) Monsoon (c) Kites (d) Rain
  31. 31.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Rain", "Kites", "Ocean"];
    show(songs[2]);     (a) Kites (b) Stars (c) Rain (d) Sunrise
  32. 32.True or false: notes to read offline fits saving on the phone. (a) True (b) False
  33. 33.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) data saved on the phone (d) a cloud backup
  34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Ocean (b) Kites (c) Sunrise
  35. 35.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
  36. 36.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a named box for a value (d) a picture
  37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Sports", "Science", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Sports (b) Art (c) Science (d) Hindi
  38. 38.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) photos on two devices (d) notes to read offline
  39. 39.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
  40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Aman", "Kabir", "Arjun", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Kabir (b) Aman (c) Arjun (d) Meera

Answer key

  1. the sound on/off setting
  2. False
  3. a shared to-do list
  4. use it on any device
  5. False
  6. 3
  7. Music
  8. 4
  9. on the phone
  10. on the phone
  11. a list
  12. 4
  13. Arjun
  14. Kabir
  15. in the cloud
  16. Ocean
  17. a draft you are typing
  18. 6
  19. Music
  20. your last game level
  21. 5
  22. a class leaderboard
  23. 4
  24. Maths
  25. on the phone
  26. False
  27. 9
  28. True
  29. True
  30. Stars
  31. Rain
  32. True
  33. data saved on the phone
  34. Kites
  35. False
  36. a named box for a value
  37. Hindi
  38. photos on two devices
  39. True
  40. Arjun

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