Database Magic - Activity

:video_game: Activity Time!

Time needed: 30-35 minutes

What you'll do

Today, you're going to build TWO amazing apps that remember things! Have you ever wondered how apps remember your high score or your favorite settings? That's the magic of databases! You'll create a Score Counter that never forgets your points and a Random Name Picker for choosing who goes first in games!

Before You Start:

• Open MIT App Inventor
• Create a new project called "DatabaseApps"
• Get ready to make apps with memory!

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Exercise One: Score Counter App

Your first app will keep track of scores and remember them even when you close the app! How cool is that?

Please watch this video to see how this app works.

Sample UI and Components

Visible and non-visible components that you will be using to make the app:

Sample UI	Components
	Layout: Vertical Arrangement Visible Components: Label Buttons Non-visible Components: TinyDB

Note: This app needs only 1 screen.

Programming Instructions

Let's make your app smart! You'll program both visible and non-visible components.

Step One: Initialize Global Variable

First, let's create a place to store our score!

Initialize a global variable (name it as score) to 0. [Hint: Only 2 blocks]

:bulb: "Stuck?"

Look in the Variables drawer for the "initialize global" block. Set the name to "score" and the value to 0!

Step 2: Press for Score Button

When the Press for score button is clicked, make these things happen:

1. Add 1 to your score (set score to score + 1)
2. Show the new score in your label
3. Save the score to TinyDB so it remembers!

:bulb: "Stuck?"

For TinyDB, use the "StoreValue" block. Set the tag to "score" and the value to your score variable!

Step 3: Clear Score Button

When the Clear score button is clicked, program it to:

1. Reset score to 0
2. Update the label to show 0
3. Save this new score (0) to the database

Step 4: App Startup Magic

This is the coolest part! When users open the app:

1. Get the saved score from TinyDB (use GetValue with tag "score")
2. Update your score variable with this saved value
3. Show the score in your label

:bulb: "Stuck?"

Use the "when Screen1.Initialize" block to make things happen when the app starts!

Test Your App!

1. Click some scores
2. Close the app completely
3. Open it again - your score should still be there!

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Exercise 2: Random Name Picker App

Time for your second app! This one picks random names - perfect for choosing teams or deciding who goes first!

Please watch this video to see how this app works.

Sample UI and Components

Visible components that you will be using to make the app:

Sample UI	Components
	Layout: Vertical Arrangement Visible Components: Button Label List Picker

Note: This app needs only 1 screen.

Programming Instructions

Let's make this fun name-picking app work!

Step One: Initialize Global Variable

Create a list of names to choose from!

Initialize a global variable (name it as names) to make a list of Teacher names.

:bulb: "Stuck?"

Use the "make a list" block from the Lists drawer. Add at least 5 teacher names like "Ms. Smith", "Mr. Johnson", etc.

Step 2: Press for Name Button

When the Press for name button is clicked, program it to:

1. Pick a random name from your list and show it in the label
2. Update the list picker with all the names

:bulb: "Stuck?"

Use the "pick a random item" block from the Lists drawer with your names variable!

Step 3: List Picker Setup

Make sure your List Picker shows all the names when clicked!

:bulb: "Stuck?"

Set the ListPicker.Elements to your names variable in the Screen1.Initialize event.

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:trophy: Challenge Yourself!

Once you've finished both apps, try these super challenges:

Score Counter Challenges:

1. High Score Tracker: Add another label that shows the highest score ever!
2. Score Multiplier: Add a x2 button that doubles your current score
3. Name Your Score: Let users type their name and save it with their score

Random Name Picker Challenges:

1. Add Names: Create a text box where users can add new names to the list
2. Remove Picked Names: Make picked names disappear so they won't be chosen again
3. Team Maker: Make it pick two names at once for team pairs!

Super Database Challenge:

Can you combine both apps? Make a game where:

• Players take turns pressing for points
• The app randomly picks who goes next
• It saves each player's score separately!

Remember: Databases are like your app's memory - they never forget! Use this power wisely to make amazing apps that remember important information.

Great job learning about databases! Your apps now have super memory powers! :tada: