EvolveFit Cairo-Squad Registration Step 3 Height And Weight Implementation Guide

by Axel Sørensen 81 views

Hey guys! Let's dive into the exciting world of implementing the third step of the registration process for EvolveFit's Cairo-Squad. This step focuses on capturing the user's height and weight information. We'll walk through the necessary code modifications, ensuring a smooth and user-friendly experience. This comprehensive guide will provide you with a detailed walkthrough of implementing the height and weight selection screen, focusing on the RegisterScreenContentSelectHeightAndWeight component. We'll cover everything from state management to UI elements, ensuring a seamless integration into the EvolveFit Cairo-Squad application.

Understanding the Requirements

Before we jump into the code, let's clarify the requirements. Our goal is to create a screen where users can input their height and weight. We need to:

  • Modify RegisterScreenState: Add variables to store the height and weight.
  • Implement RegisterInteractionListener: Add functions to set the height and weight.
  • Update RegisterViewModel: Implement the functions to handle height and weight input.
  • Create RegisterScreenContentSelectHeightAndWeight: Build the UI for height and weight selection, making sure there's no top bar or next button created here.
  • Disable Next Button (If Needed): Use the nextButtonEnabled variable in RegisterScreenState to control the next button's state.

With these requirements in mind, let's start coding! Our primary focus will be on creating a seamless user experience for inputting height and weight during the registration process. To achieve this, we'll need to carefully consider the UI design, data validation, and state management within our application. The goal is to make the process intuitive and error-free for the user. We'll also ensure that the entered data is properly stored and utilized in subsequent steps of the registration.

1. Modifying RegisterScreenState

First, we need to add the height and weight variables to the RegisterScreenState file. This will allow us to store the user's input within the application's state. These variables will hold the numerical values representing the user's height and weight, respectively. By including them in the state, we ensure that the data is readily accessible and can be easily managed as the user progresses through the registration flow. This approach to data management will also enable us to implement features like real-time validation and display of entered values. Let's get started by opening the RegisterScreenState file and adding the following:

data class RegisterScreenState(
    // Existing state variables
    val height: String = "",
    val weight: String = "",
    val nextButtonEnabled: Boolean = false // Initially disabled
)

Here, we've added two String variables, height and weight, initialized to empty strings. We've also kept the nextButtonEnabled variable, which we'll use later to control the next button's state based on whether the user has entered valid height and weight information. The String type allows us to handle input as text initially, providing flexibility in formatting and validation. We can later convert these strings to numerical values as needed for calculations or storage. Now, let's move on to the next step, which involves defining functions to update these state variables.

2. Implementing RegisterInteractionListener

Next up, we need to add functions to the RegisterInteractionListener interface. These functions will act as contracts, defining how the UI can interact with the ViewModel to set the height and weight. By defining these functions in the interface, we maintain a clear separation of concerns, making our code more testable and maintainable. The interface acts as a bridge between the UI and the ViewModel, allowing them to communicate without direct dependencies. This approach promotes modularity and flexibility in our codebase. Let's add the setHeight and setWeight functions to the RegisterInteractionListener interface:

interface RegisterInteractionListener {
    // Existing listener functions
    fun setHeight(height: String)
    fun setWeight(weight: String)
}

These functions, setHeight and setWeight, each take a String parameter representing the user's input. This allows us to capture the input directly from the UI elements and pass it to the ViewModel for processing. The use of String here again provides flexibility in handling different input formats and allows for easy validation before converting to other data types. Now that we've defined the interface, we need to implement these functions in our ViewModel. This is where we'll handle the logic of updating the state based on the user's input.

3. Updating RegisterViewModel

Now comes the crucial part: implementing the setHeight and setWeight functions within the RegisterViewModel. This is where the magic happens – we'll update the RegisterScreenState based on the user's input. In the RegisterViewModel, we'll receive the height and weight values from the UI and update the corresponding state variables. This ensures that the UI reflects the current data entered by the user. Additionally, we'll manage the nextButtonEnabled state based on the validity of the entered height and weight. This allows us to control the flow of the registration process, ensuring that the user completes all required fields before proceeding. Let's take a look at how we can implement these functions within the RegisterViewModel:

class RegisterViewModel : ViewModel(), RegisterInteractionListener {
    // Existing state and other functions

    private val _state = MutableStateFlow(RegisterScreenState())
    val state = _state.asStateFlow()

    override fun setHeight(height: String) {
        _state.update { it.copy(height = height) }
        updateNextButtonEnabled()
    }

    override fun setWeight(weight: String) {
        _state.update { it.copy(weight = weight) }
        updateNextButtonEnabled()
    }

    private fun updateNextButtonEnabled() {
        _state.update { it.copy(nextButtonEnabled = it.height.isNotBlank() && it.weight.isNotBlank()) }
    }
}

In this snippet, we've implemented the setHeight and setWeight functions. Each function updates the _state (a MutableStateFlow holding the RegisterScreenState) with the new height or weight value. We use the copy function to create a new instance of the state with the updated value, ensuring immutability. After each update, we call updateNextButtonEnabled to check if both height and weight are non-empty. This function updates the nextButtonEnabled flag in the state, which we'll use in the UI to enable or disable the next button. By using StateFlow, we ensure that the UI automatically updates whenever the state changes, providing a reactive and efficient way to manage the UI's state. Now that we've handled the state management, let's move on to creating the UI for height and weight selection.

4. Creating RegisterScreenContentSelectHeightAndWeight

Now for the main event: creating the RegisterScreenContentSelectHeightAndWeight composable function! This is where we'll build the UI for capturing the user's height and weight. Remember, we don't need to create a top bar or next button in this composable. We'll focus solely on the input fields for height and weight. This composable will contain two primary UI elements: input fields for height and weight. We'll use TextField components from Compose to allow users to enter their data. Each TextField will have a label indicating the expected input (e.g.,