Dashboard Logic

Now you will build the logic that combines your data into useful summaries.

The dashboard is where users quickly see:

how many tasks they have
how many tasks are completed
how much they have spent

This is where your application starts to feel like a real product.

Goal of This Lesson

By the end of this lesson, you will:

calculate task statistics
calculate expense summaries
combine data from multiple services
prepare data for display in the GUI

Step 1: Create Dashboard Service File

Create:

text

app/services/dashboard_service.py

Step 2: Import Required Services

python

from app.services.task_service import get_tasks
from app.services.expense_service import get_total_expenses

Step 3: Total Task Count

python

def get_total_tasks(user_id):
    tasks = get_tasks(user_id)
    return len(tasks)

Step 4: Completed Task Count

python

def get_completed_tasks(user_id):
    tasks = get_tasks(user_id)
    completed = [task for task in tasks if task[2] == 1]
    return len(completed)

Step 5: Expense Summary

python

def get_expense_total(user_id):
    return get_total_expenses(user_id)

Step 6: Combine Dashboard Data

python

def get_dashboard_data(user_id):
    return {
        "total_tasks": get_total_tasks(user_id),
        "completed_tasks": get_completed_tasks(user_id),
        "total_expenses": get_expense_total(user_id)
    }

Step 7: Test in main.py

Update your main.py:

python

from app.services.database import create_tables
from app.services.user_service import register_user, login_user
from app.services.task_service import add_task
from app.services.expense_service import add_expense
from app.services.dashboard_service import get_dashboard_data

def main():
    create_tables()

    register_user("tom", "123")
    user_id = login_user("tom", "123")

    # add sample data
    add_task(user_id, "Study Python")
    add_task(user_id, "Build App")
    add_expense(user_id, 20, "Food")
    add_expense(user_id, 40, "Transport")

    dashboard = get_dashboard_data(user_id)
    print(dashboard)

if __name__ == "__main__":
    main()

Example Output

text

{
    'total_tasks': 2,
    'completed_tasks': 0,
    'total_expenses': 60
}

Data Structure

Dashboard data:

text

{
    total_tasks,
    completed_tasks,
    total_expenses
}

Why This Step Matters

You are now combining multiple features into one view.

This is how real applications:

summarize data
display insights
provide value to users

Current Project Structure

text

app/
    services/
        database.py
        user_service.py
        task_service.py
        expense_service.py
        dashboard_service.py

Important Notes

Keep logic separate from GUI
Return clean data structures (like dictionaries)
Avoid printing inside service files

Summary

You built dashboard logic that combines task and expense data into a single summary for the user.