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TLDR;
This video provides a step-by-step tutorial on how to create a Rock Paper Scissors game in Code.org's App Lab. It covers designing the user interface with welcome, game, and results screens, implementing the game logic using variables and functions, and adding interactive elements with event handlers. The tutorial also includes debugging tips and suggestions for expanding the game with a scoreboard.
- Creating a Rock Paper Scissors game in Code.org's App Lab.
- Designing the user interface with welcome, game, and results screens.
- Implementing the game logic using variables and functions.
- Adding interactive elements with event handlers.
- Debugging tips and suggestions for expanding the game with a scoreboard.
Introduction [0:00]
The video introduces a tutorial on creating a Rock Paper Scissors game using Code.org's App Lab. The game features a welcome screen, a game screen with rock, paper, and scissors options, and a results screen that displays the outcome with corresponding background colors (yellow for a tie, green for a win, and red for a loss). The game also tracks the number of wins, losses, and draws.
Setting Up the Project and Designing the UI [1:41]
To begin, a new project is created in Code.org's App Lab. The project requires three screens: "welcome," "game," and "results." The "welcome" screen includes a label welcoming the player and a "play game" button. The "game" screen features a label prompting the user to select rock, paper, or scissors, along with three corresponding buttons. The "results" screen contains static labels ("You chose," "Computer chose," "Winner") and dynamic labels that will display the choices and the outcome of the game. A "play again" button is also added to the "results" screen.
Coding the Welcome Screen and Setting Up Variables [5:04]
The tutorial starts coding with an on-event function for the "play game" button on the welcome screen, which navigates the user to the game screen using the setScreen function. To manage the game's logic, variables are introduced: "computerChoice" is assigned a random number between 1 and 3 (representing rock, paper, and scissors), and "userChoice" is declared to store the user's selection later.
Implementing User Choices and Custom Functions [7:14]
Three on-event functions are created for the rock, paper, and scissors buttons. Each function sets the "userChoice" variable to 1, 2, or 3, respectively, based on the user's selection. The text of the "choiceLabel" is also updated to reflect the user's choice. Two custom functions, "displayComputerChoice" and "calculateWinner," are defined to handle the computer's choice and determine the game's outcome.
Displaying the Computer's Choice [9:04]
The "displayComputerChoice" function uses conditional statements to set the text of the "computerChoiceLabel" based on the value of the "computerChoice" variable. If "computerChoice" is 1, the label displays "rock"; if it's 2, it displays "paper"; and if it's 3, it displays "scissors." This function translates the numerical choice of the computer into a readable text for the user.
Calling Functions and Testing the Game [10:26]
The "calculateWinner" and "displayComputerChoice" functions are called within each of the rock, paper, and scissors button event handlers. Additionally, the screen is set to the results screen after a choice is made. The game is tested to ensure that the screen navigation and computer choice display are functioning correctly. The tutorial also shows how to use console.log to output the computer's choice to the debug console for testing purposes.
Debugging and Improving the UI [11:55]
The video addresses some UI issues, such as labels not being wide enough to display the results. The labels on the results screen are adjusted to ensure they can accommodate the text. The game is tested again to confirm that the UI improvements are effective.
Implementing the Game Logic in the Calculate Winner Function [13:53]
The "calculateWinner" function is implemented using nested conditional statements to determine the outcome of the game. If the user's choice and the computer's choice are the same, it's a draw, and the background color of the results screen is set to yellow. Otherwise, a series of if-else statements check all possible combinations of user and computer choices to determine the winner. The text of the "winnerLabel" is set to "You" if the user wins or "Computer" if the computer wins, and the background color of the results screen is set to green or red accordingly.
Completing the Game Logic and Testing [17:55]
The tutorial emphasizes the importance of carefully checking the spelling and logic of the code to ensure that all possible outcomes are handled correctly. The use of copy-pasting code is suggested to speed up the process, but it's crucial to verify that the values are updated correctly in each instance. The game is tested to ensure that the win/loss conditions are accurately determined and displayed.
Coding the Play Again Button and Final Testing [19:24]
An on-event function is created for the "play again" button on the results screen. When clicked, this button generates a new random number for the "computerChoice" variable and navigates the user back to the game screen. This allows the user to play the game again without resetting the app. The game is tested one final time to ensure that all features are working as expected.
Additional Challenge: Implementing a Scoreboard [20:48]
As an additional challenge, the tutorial suggests implementing a scoreboard to keep track of the number of wins, losses, and draws. This would involve creating three new variables (one for each category), updating these variables each time a game is played, and displaying their values using labels on the screen.
