To create a program that draws a wall of circles one at a time using a timer, you can use the following steps:
1. Set up the graphical environment:
- Create a window or canvas where you can draw the circles.
- Define the size of the window to cover the entire screen.
2. Create a timer:
- Set a delay interval (DELAY) in milliseconds between each circle drawing.
- Connect the timer to a callback function that will draw one circle each time it is triggered.
3. Implement the drawing logic inside the callback function:
- Define a variable to keep track of the current row and column position of the circles. Start with row 0 and column 0.
- Create a variable to track the color of the circles, starting with red.
- In the callback function, draw a circle based on the current row and column position using an appropriate graphics library.
- After drawing a circle, update the row and column position:
- If the column is at the far right, move to the next row and reset the column to 0.
- If the column is not at the far right, move to the next column.
- Switch the color between red and black for each circle drawn.
4. Stop the timer:
- After drawing circles covering the entire screen, stop the timer to prevent further circle drawings.
Here's a sample Python code using the tkinter library to implement this program:
```python
import tkinter as tk
DELAY = 100 # Delay in milliseconds
ROW_COUNT = 10
COLUMN_COUNT = 10
CIRCLE_RADIUS = 20
WINDOW_WIDTH = COLUMN_COUNT * 2 * CIRCLE_RADIUS
WINDOW_HEIGHT = ROW_COUNT * 2 * CIRCLE_RADIUS
def draw_circle():
global row, column, color
canvas.create_oval(
column * 2 * CIRCLE_RADIUS, row * 2 * CIRCLE_RADIUS,
(column + 1) * 2 * CIRCLE_RADIUS, (row + 1) * 2 * CIRCLE_RADIUS,
fill=color
)
column += 1
if column >= COLUMN_COUNT:
row += 1
column = 0
color = "black" if color == "red" else "red"
if row >= ROW_COUNT:
root.after_cancel(timer) # Stop the timer
root = tk.Tk()
canvas = tk.Canvas(root, width=WINDOW_WIDTH, height=WINDOW_HEIGHT)
canvas.pack()
row = 0
column = 0
color = "red"
timer = root.after(DELAY, draw_circle)
root.mainloop()
```
This code sets up a tkinter window of size `WINDOW_WIDTH` by `WINDOW_HEIGHT` and creates a `canvas` object to draw the circles. It then defines the `draw_circle` function as the callback for the timer.
The `draw_circle` function uses the `create_oval` method of the canvas object to draw a circle based on the current `row` and `column` position. It then updates the `row` and `column` variables and switches the color between red and black.
The timer is initialized using the `after` method of the `root` object, which triggers the `draw_circle` function every `DELAY` milliseconds. Finally, the main event loop is started with `root.mainloop()`, allowing the program to respond to user interactions and timed events.