如何在Ubuntu中使用Python显示屏幕键盘

在Ubuntu中，可以使用Python和一些库来创建和显示屏幕键盘。本教程将展示如何使用Python和Pygame库来创建可自定义的屏幕键盘，并将其集成到您的应用程序中。

步骤一：安装必要库

需要两个库才能创建和显示屏幕键盘：pygame和pynput。

sudo apt-get update
sudo apt-get install python3-pygame
pip3 install pynput

步骤二：创建键盘图像

接下来，我们创建一个Python脚本来生成我们的键盘图像。文件键盘.png将被创建并用于在Pygame屏幕上绘制我们的键盘。

from PIL import Image, ImageDraw

# 设置图像大小
width, height = 800, 300

# 创建红色背景
img = Image.new("RGB", (width, height), (255, 0, 0))

# 创建图像绘制对象
draw = ImageDraw.Draw(img)

# 定义按键列表
keys = [
    "Esc", "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8",
    "F9", "F10", "F11", "F12", "PrtSc", "ScrLk", "Pause",
    "`", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0",
    "-", "=", "BkSp", "Ins", "Home", "PgUp", "NumLk", "/",
    "*", "-", "\n",
    "Tab", "Q", "W", "E", "R", "T", "Y", "U", "I", "O", "P",
    "[", "]", "\\", "Del", "End", "PgDn", "7", "8", "9", "+",
    "Caps Lk", "A", "S", "D", "F", "G", "H", "J", "K", "L",
    ";", "'", "#", "4", "5", "6",
    "Shift", "Z", "X", "C", "V", "B", "N", "M", ",", ".", "/",
    "Shift", "Up", "1", "2", "3", "Enter",
    "Ctrl", "Win", "Alt", "Space", "Alt", "Fn", "Ctrl", "Left",
    "Down", "Right", "0", ".", "<"
]

# 定义按键大小和位置
key_size = 40
x, y = 20, 30
padding_x, padding_y = 10, 10

# 循环所有按键并绘制它们
for key in keys:
    draw.rectangle(
        (x, y, x + key_size, y + key_size),
        outline=(255, 255, 255)
    )
    x += key_size + padding_x  # 移动到右侧的按键列
    if x + key_size > width:  # 开始新行
        x = 20
        y += key_size + padding_y

# 将图像保存为文件
img.save("keyboard.png")

步骤三：显示键盘

我们现在有一个可用的键盘图像，我们可以使用Pygame显示它。因此，我们将编写一个新脚本来显示键盘并设置键盘按键的应答事件。

import pygame
from pynput import keyboard

# 初始化Pygame
pygame.init()

# 定义按键列表
keys = [
    "Esc", "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8",
    "F9", "F10", "F11", "F12", "PrtSc", "ScrLk", "Pause",
    "`", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0",
    "-", "=", "BkSp", "Ins", "Home", "PgUp", "NumLk", "/",
    "*", "-", "\n",
    "Tab", "Q", "W", "E", "R", "T", "Y", "U", "I", "O", "P",
    "[", "]", "\\", "Del", "End", "PgDn", "7", "8", "9", "+",
    "Caps Lk", "A", "S", "D", "F", "G", "H", "J", "K", "L",
    ";", "'", "#", "4", "5", "6",
    "Shift", "Z", "X", "C", "V", "B", "N", "M", ",", ".", "/",
    "Shift", "Up", "1", "2", "3", "Enter",
    "Ctrl", "Win", "Alt", "Space", "Alt", "Fn", "Ctrl", "Left",
    "Down", "Right", "0", ".", "<"
]

# 加载键盘图像
keyboard_image = pygame.image.load("keyboard.png")

# 获取键盘图像尺寸
keyboard_rect = keyboard_image.get_rect()

# 定义屏幕尺寸和位置
screen_size = (keyboard_rect.width, keyboard_rect.height + 100)
screen_position = (50,50)

# 创建Pygame屏幕
screen = pygame.display.set_mode(screen_size)
pygame.display.set_caption("屏幕键盘")
pygame.display.set_icon(pygame.Surface((1, 1)))  # 隐藏Pygame默认的 icon

# 设置显示比例和背景颜色
scale = 1
background_color = (255, 255, 255)

# 重设键盘大小
keyboard_image = pygame.transform.scale(
    keyboard_image, (int(scale*keyboard_rect.width), int(scale*keyboard_rect.height))
)

# 创建键盘位置
keyboard_position = (
    int((screen_size[0] - scale*keyboard_rect.width)/2),
    int(screen_size[1]*0.05)
)

# 绘制背景
screen.fill(background_color)

# 绘制键盘
screen.blit(keyboard_image, keyboard_position)

# 设置字体并绘制文本
font = pygame.font.SysFont(None, 40)
text = font.render("按下/松开按键以查看反应", True, (0, 0, 0))
text_rect = text.get_rect()
text_rect.center = (screen_size[0]/2, screen_size[1] - 50)
screen.blit(text, text_rect)

# 更新屏幕
pygame.display.flip()

# 定义按键的按下和松开事件
def on_press(key):
    try:
        index = keys.index(str(key))
        # 按键按下，展示反应
        draw_rectangle(index, (0, 0, 255))
        pygame.display.flip()

    except ValueError:
        pass

def on_release(key):
    try:
        index = keys.index(str(key))
        # 按键释放，展示反应
        draw_rectangle(index, background_color)
        pygame.display.flip()

    except ValueError:
        pass

# 绘制按键
def draw_rectangle(key_index, color):
    x = 20
    y = 30
    key_size = 40
    padding_x = 10
    padding_y = 10
    
    # 计算按键坐标
    row = key_index // 17
    col = key_index % 17

    x += col * (key_size + padding_x)
    y += row * (key_size + padding_y)

    # 绘制矩形
    pygame.draw.rect(screen, color, (x*scale + keyboard_position[0], y*scale + keyboard_position[1], key_size*scale, key_size*scale))

# 监听键盘事件
with keyboard.Listener(on_press=on_press, on_release=on_release) as listener:
    listener.join()

# 循环事件，不进行处理即可退出
while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            quit()

现在，您应该能够运行此脚本以显示自己的屏幕键盘！您还可以定制键盘以适应您的应用程序需要。