mirror of
https://github.com/LCTT/TranslateProject.git
synced 2024-12-26 21:30:55 +08:00
846 lines
34 KiB
Markdown
846 lines
34 KiB
Markdown
[#]: subject: "Crash Course On Using Textual"
|
||
[#]: via: "https://fedoramagazine.org/crash-course-on-using-textual/"
|
||
[#]: author: "Jose Nunez https://fedoramagazine.org/author/josevnz/"
|
||
[#]: collector: "lujun9972/lctt-scripts-1700446145"
|
||
[#]: translator: "ChatGPT"
|
||
[#]: reviewer: "wxy"
|
||
[#]: publisher: "wxy"
|
||
[#]: url: "https://linux.cn/article-16557-1.html"
|
||
|
||
Textual:为 Python 增加漂亮的文本用户界面(TUI)
|
||
======
|
||
|
||
![][0]
|
||
|
||
### 快速入门使用 Textual
|
||
|
||
Python 在 Linux 上有像 [TkInter][4] 这样的优秀 GUI(图形用户界面)开发库,但如果你不能运行图形应用程序怎么办?
|
||
|
||
文本终端,并非只在 Linux 上有,而且 BSD 和其它的出色的类 Unix 操作系统上也有。如果你的代码是用 Python 编写的,你应该使用 [Textual][5] 来帮助你编写 TUI(文本用户界面)。在这个快速介绍中,我将向你展示两个你可以用 Textual 做的示例,并且介绍它未来可能的应用方向。
|
||
|
||
所以 Textual 是什么?
|
||
|
||
> Textual 是一个为 Python 构建的快速应用程序开发框架,由 Textualize.io 构建。它可以让你用简单的 Python API 构建复杂的用户界面,并运行在终端或网络浏览器上!
|
||
|
||
#### 你需要的跟进这个教程的工具
|
||
|
||
你需要有以下条件:
|
||
|
||
1. 具备基础的编程经验,最好熟练使用 Python。
|
||
2. 理解基础的面向对象概念,比如类和继承。
|
||
3. 一台安装了 Linux 与 Python 3.9+ 的机器
|
||
4. 一款好的编辑器(Vim 或者 PyCharm 是不错的选择)
|
||
|
||
我尽可能简单化代码,以便你能轻松理解。此外,我强烈建议你下载代码,或至少按照接下来的说明安装相关程序。
|
||
|
||
#### 安装步骤
|
||
|
||
首先创建一个虚拟环境:
|
||
|
||
```
|
||
python3 -m venv ~/virtualenv/Textualize
|
||
```
|
||
|
||
现在,你可以克隆 Git 仓库并创建一个可以编辑的发布版本:
|
||
|
||
```
|
||
. ~/virtualenv/Textualize/bin/activate
|
||
pip install --upgrade pip
|
||
pip install --upgrade wheel
|
||
pip install --upgrade build
|
||
pip install --editable .
|
||
```
|
||
|
||
或者直接从 Pypi.org 安装:
|
||
|
||
```
|
||
. ~/virtualenv/Textualize/bin/activate
|
||
pip install --upgrade KodegeekTextualize
|
||
```
|
||
|
||
### 我们的首个程序:日志浏览器
|
||
|
||
![][6]
|
||
|
||
这个 _日志浏览器_ 就是一款简单的应用,能执行用户 _[PATH][7]_ 路径上的一系列 UNIX 命令,并在任务执行完毕后捕获输出。
|
||
|
||
以下是该应用的代码:
|
||
|
||
```
|
||
import shutil
|
||
from textual import on
|
||
from textual.app import ComposeResult, App
|
||
from textual.widgets import Footer, Header, Button, SelectionList
|
||
from textual.widgets.selection_list import Selection
|
||
from textual.screen import ModalScreen
|
||
# Operating system commands are hardcoded
|
||
OS_COMMANDS = {
|
||
"LSHW": ["lshw", "-json", "-sanitize", "-notime", "-quiet"],
|
||
"LSCPU": ["lscpu", "--all", "--extended", "--json"],
|
||
"LSMEM": ["lsmem", "--json", "--all", "--output-all"],
|
||
"NUMASTAT": ["numastat", "-z"]
|
||
}
|
||
|
||
class LogScreen(ModalScreen):
|
||
# ... Code of the full separate screen omitted, will be explained next
|
||
def __init__(self, name = None, ident = None, classes = None, selections = None):
|
||
super().__init__(name, ident, classes)
|
||
pass
|
||
|
||
class OsApp(App):
|
||
BINDINGS = [
|
||
("q", "quit_app", "Quit"),
|
||
]
|
||
CSS_PATH = "os_app.tcss"
|
||
ENABLE_COMMAND_PALETTE = False # Do not need the command palette
|
||
|
||
def action_quit_app(self):
|
||
self.exit(0)
|
||
|
||
def compose(self) -> ComposeResult:
|
||
# Create a list of commands, valid commands are assumed to be on the PATH variable.
|
||
selections = [Selection(name.title(), ' '.join(cmd), True) for name, cmd in OS_COMMANDS.items() if shutil.which(cmd[0].strip())]
|
||
yield Header(show_clock=False)
|
||
sel_list = SelectionList(*selections, id='cmds')
|
||
sel_list.tooltip = "Select one more more command to execute"
|
||
yield sel_list
|
||
yield Button(f"Execute {len(selections)} commands", id="exec", variant="primary")
|
||
yield Footer()
|
||
|
||
@on(SelectionList.SelectedChanged)
|
||
def on_selection(self, event: SelectionList.SelectedChanged) -> None:
|
||
button = self.query_one("#exec", Button)
|
||
selections = len(event.selection_list.selected)
|
||
if selections:
|
||
button.disabled = False
|
||
else:
|
||
button.disabled = True
|
||
button.label = f"Execute {selections} commands"
|
||
|
||
@on(Button.Pressed)
|
||
def on_button_click(self):
|
||
selection_list = self.query_one('#cmds', SelectionList)
|
||
selections = selection_list.selected
|
||
log_screen = LogScreen(selections=selections)
|
||
self.push_screen(log_screen)
|
||
|
||
def main():
|
||
app = OsApp()
|
||
app.title = f"Output of multiple well known UNIX commands".title()
|
||
app.sub_title = f"{len(OS_COMMANDS)} commands available"
|
||
app.run()
|
||
|
||
if __name__ == "__main__":
|
||
main()
|
||
```
|
||
|
||
现在我们逐条梳理一下程序的代码:
|
||
|
||
1. 每个应用都扩展自 `App` 类。其中最重要的有 `compose` 与 `mount` 等方法。但在当前应用中,我们只实现了 [compose][8]。
|
||
2. 在 `compose` 方法中,你会返回一系列 <ruby>[组件][9]<rt>Widget</rt></ruby>,并按顺序添加到主屏幕中。每一个组件都有定制自身外观的选项。
|
||
3. 你可以设定单字母的 <ruby>[绑定][10]<rt>binding</rt></ruby>,比如此处我们设定了 `q` 键来退出应用(参见 `action_quit_app` 函数和 `BINDINGS` 列表)。
|
||
4. 利用 `SelectionList` 组件,我们展示了待运行的命令列表。然后,你可以通过 `@on(SelectionList.SelectedChanged)` 注解以及 `on_selection` 方法告知应用获取所选的内容。
|
||
5. 对于无选定元素的应对很重要,我们会根据运行的命令数量来决定是否禁用 “exec” 按钮。
|
||
6. 我们使用类似的监听器( `@on(Button.Pressed)` )来执行命令。我们做的就是将我们的选择送到一个新的屏幕,该屏幕会负责执行命令并收集结果。
|
||
|
||
你注意到 `CSS_PATH = "os_app.tcss"` 这个变量了吗?Textual 允许你使用 CSS 来控制单个或多个组件的外观(色彩、位置、尺寸):
|
||
|
||
```
|
||
Screen {
|
||
layout: vertical;
|
||
}
|
||
|
||
Header {
|
||
dock: top;
|
||
}
|
||
|
||
Footer {
|
||
dock: bottom;
|
||
}
|
||
|
||
SelectionList {
|
||
padding: 1;
|
||
border: solid $accent;
|
||
width: 1fr;
|
||
height: 80%;
|
||
}
|
||
|
||
Button {
|
||
width: 1fr
|
||
}
|
||
```
|
||
|
||
引自 Textual 官方网站:
|
||
|
||
> Textual 中使用的 CSS 是互联网上常见 CSS 的简化版本,容易上手。
|
||
|
||
_这真是太棒了_,只需要用一哥独立的 [样式表][12],就可以轻松调整应用的样式。
|
||
|
||
好,我们现在来看看如何在新屏幕上展示结果。
|
||
|
||
#### 在新屏幕上展示结果
|
||
|
||
![][13]
|
||
|
||
以下是在新屏幕上处理输出的代码:
|
||
|
||
```
|
||
import asyncio
|
||
from typing import List
|
||
from textual import on, work
|
||
from textual.reactive import reactive
|
||
from textual.screen import ModalScreen
|
||
from textual.widgets import Button, Label, Log
|
||
from textual.worker import Worker
|
||
from textual.app import ComposeResult
|
||
|
||
class LogScreen(ModalScreen):
|
||
count = reactive(0)
|
||
MAX_LINES = 10_000
|
||
ENABLE_COMMAND_PALETTE = False
|
||
CSS_PATH = "log_screen.tcss"
|
||
|
||
def __init__(
|
||
self,
|
||
name: str | None = None,
|
||
ident: str | None = None,
|
||
classes: str | None = None,
|
||
selections: List = None
|
||
):
|
||
super().__init__(name, ident, classes)
|
||
self.selections = selections
|
||
|
||
def compose(self) -> ComposeResult:
|
||
yield Label(f"Running {len(self.selections)} commands")
|
||
event_log = Log(
|
||
id='event_log',
|
||
max_lines=LogScreen.MAX_LINES,
|
||
highlight=True
|
||
)
|
||
event_log.loading = True
|
||
yield event_log
|
||
button = Button("Close", id="close", variant="success")
|
||
button.disabled = True
|
||
yield button
|
||
|
||
async def on_mount(self) -> None:
|
||
event_log = self.query_one('#event_log', Log)
|
||
event_log.loading = False
|
||
event_log.clear()
|
||
lst = '\n'.join(self.selections)
|
||
event_log.write(f"Preparing:\n{lst}")
|
||
event_log.write("\n")
|
||
|
||
for command in self.selections:
|
||
self.count += 1
|
||
self.run_process(cmd=command)
|
||
|
||
def on_worker_state_changed(self, event: Worker.StateChanged) -> None:
|
||
if self.count == 0:
|
||
button = self.query_one('#close', Button)
|
||
button.disabled = False
|
||
self.log(event)
|
||
|
||
@work(exclusive=False)
|
||
async def run_process(self, cmd: str) -> None:
|
||
event_log = self.query_one('#event_log', Log)
|
||
event_log.write_line(f"Running: {cmd}")
|
||
# Combine STDOUT and STDERR output
|
||
proc = await asyncio.create_subprocess_shell(
|
||
cmd,
|
||
stdout=asyncio.subprocess.PIPE,
|
||
stderr=asyncio.subprocess.STDOUT
|
||
)
|
||
stdout, _ = await proc.communicate()
|
||
if proc.returncode != 0:
|
||
raise ValueError(f"'{cmd}' finished with errors ({proc.returncode})")
|
||
stdout = stdout.decode(encoding='utf-8', errors='replace')
|
||
if stdout:
|
||
event_log.write(f'\nOutput of "{cmd}":\n')
|
||
event_log.write(stdout)
|
||
self.count -= 1
|
||
|
||
@on(Button.Pressed, "#close")
|
||
def on_button_pressed(self, _) -> None:
|
||
self.app.pop_screen()
|
||
|
||
```
|
||
|
||
你会注意到:
|
||
|
||
1. `LogScreen` 类扩展自 `ModalScreen` 类, 该类负责处理模态模式的屏幕。
|
||
2. 这个屏幕同样有一个 `compose` 方法,我们在这里添加了组件以展示 Unix 命令的内容。
|
||
3. 我们创建了一个叫做 `mount` 的新方法。一旦你用 `compose` 编排好组件,你就可以运行代码来获取数据,并再进一步定制它们的外观。
|
||
4. 我们使用 [asyncio][14] 运行命令,这样我们就能让 TUI 主工作线程在每个命令的结果出来时就及时更新内容。
|
||
5. 对于“工作线程”,请注意 `run_process` 方法上的 `@work(exclusive=False)` 注解,该方法用于运行命令并捕获 STDOUT + STDERR 输出。使用 [工作线程][15] 来管理并发并不复杂,尽管它们在手册中确实有专门的章节。这主要是因为运行的外部命令可能会执行很长时间。
|
||
6. 在 `run_process` 中,我们通过调用 `write` 以命令的输出内容来更新 `event_log`。
|
||
7. 最后,`on_button_pressed` 把我们带回到前一屏幕(从堆栈中移除屏幕)。
|
||
|
||
这个小应用向你展示了如何一份不到 200 行的代码来编写一个简单的前端,用来运行非 Python 代码。
|
||
|
||
现在我们来看一个更复杂的例子,这个例子用到了我们还未探索过的 Textual 的新特性。
|
||
|
||
### 示例二:展示赛事成绩的表格
|
||
|
||
![通过 Textual 创建的表格应用][16]
|
||
|
||
本示例将展示如何使用 `DataTable` 组件在表格中展示赛事成绩。你能通过这个应用实现:
|
||
|
||
* 通过列来排序表格
|
||
* 选择表格中的行,完整窗口展示赛事细节,我们将使用我们在日志浏览器中看到的 “推送屏幕” 技巧。
|
||
* 能进行表格搜索,查看选手详情,或执行其他操作如退出应用。
|
||
|
||
下面,我们来看看应用代码:
|
||
|
||
```
|
||
|
||
#!/usr/bin/env python
|
||
"""
|
||
Author: Jose Vicente Nunez
|
||
"""
|
||
from typing import Any, List
|
||
|
||
from rich.style import Style
|
||
from textual import on
|
||
from textual.app import ComposeResult, App
|
||
from textual.command import Provider
|
||
from textual.screen import ModalScreen, Screen
|
||
from textual.widgets import DataTable, Footer, Header
|
||
|
||
MY_DATA = [
|
||
("level", "name", "gender", "country", "age"),
|
||
("Green", "Wai", "M", "MYS", 22),
|
||
("Red", "Ryoji", "M", "JPN", 30),
|
||
("Purple", "Fabio", "M", "ITA", 99),
|
||
("Blue", "Manuela", "F", "VEN", 25)
|
||
]
|
||
|
||
class DetailScreen(ModalScreen):
|
||
ENABLE_COMMAND_PALETTE = False
|
||
CSS_PATH = "details_screen.tcss"
|
||
|
||
def __init__(
|
||
self,
|
||
name: str | None = None,
|
||
ident: str | None = None,
|
||
classes: str | None = None,
|
||
row: List[Any] | None = None,
|
||
):
|
||
super().__init__(name, ident, classes)
|
||
# Rest of screen code will be show later
|
||
|
||
class CustomCommand(Provider):
|
||
|
||
def __init__(self, screen: Screen[Any], match_style: Style | None = None):
|
||
super().__init__(screen, match_style)
|
||
self.table = None
|
||
# Rest of provider code will be show later
|
||
|
||
class CompetitorsApp(App):
|
||
BINDINGS = [
|
||
("q", "quit_app", "Quit"),
|
||
]
|
||
CSS_PATH = "competitors_app.tcss"
|
||
# Enable the command palette, to add our custom filter commands
|
||
ENABLE_COMMAND_PALETTE = True
|
||
# Add the default commands and the TablePopulateProvider to get a row directly by name
|
||
COMMANDS = App.COMMANDS | {CustomCommand}
|
||
|
||
def action_quit_app(self):
|
||
self.exit(0)
|
||
|
||
def compose(self) -> ComposeResult:
|
||
yield Header(show_clock=True)
|
||
|
||
table = DataTable(id=f'competitors_table')
|
||
table.cursor_type = 'row'
|
||
table.zebra_stripes = True
|
||
table.loading = True
|
||
yield table
|
||
yield Footer()
|
||
|
||
def on_mount(self) -> None:
|
||
table = self.get_widget_by_id(f'competitors_table', expect_type=DataTable)
|
||
columns = [x.title() for x in MY_DATA[0]]
|
||
table.add_columns(*columns)
|
||
table.add_rows(MY_DATA[1:])
|
||
table.loading = False
|
||
table.tooltip = "Select a row to get more details"
|
||
|
||
@on(DataTable.HeaderSelected)
|
||
def on_header_clicked(self, event: DataTable.HeaderSelected):
|
||
table = event.data_table
|
||
table.sort(event.column_key)
|
||
|
||
@on(DataTable.RowSelected)
|
||
def on_row_clicked(self, event: DataTable.RowSelected) -> None:
|
||
table = event.data_table
|
||
row = table.get_row(event.row_key)
|
||
runner_detail = DetailScreen(row=row)
|
||
self.show_detail(runner_detail)
|
||
|
||
def show_detail(self, detailScreen: DetailScreen):
|
||
self.push_screen(detailScreen)
|
||
|
||
def main():
|
||
app = CompetitorsApp()
|
||
app.title = f"Summary".title()
|
||
app.sub_title = f"{len(MY_DATA)} users"
|
||
app.run()
|
||
|
||
if __name__ == "__main__":
|
||
main()
|
||
```
|
||
|
||
有哪些部分值得我们关注呢?
|
||
|
||
1. `compose` 方法中添加了 [表头][17],“命令面板” 就位于此处,我们的表格([DataTable][18])也在这里。表格数据在 `mount` 方法中填充。
|
||
2. 我们设定了预期的绑定(`BINDINGS`),并指定了外部的 CSS 文件来设置样式(`CSS_PATH`)。
|
||
3. 默认情况下,我们无需任何设置便能使用 [命令面板][19],但在此我们显式启用了它(`ENABLE_COMMAND_PALETTE = True`)。
|
||
4. 我们的应用有一个自定义表格搜索功能。当用户输入一名选手的名字后,应用会显示可能的匹配项,用户可以点击匹配项查看该选手的详细信息。这需要告诉应用我们有一个定制的命令提供者(`COMMANDS = App.COMMANDS | {CustomCo_ mmand}`),即类 `CustomCommand(Provider)`。
|
||
5. 如果用户点击了表头,表格内容会按照该列进行排序。这是通过 `on_header_clicked` 方法实现的,该方法上具有 `@on(DataTable.HeaderSelected)` 注解。
|
||
6. 类似地,当选中表格中的一行时, `on_row_clicked` 方法会被调用,这得益于它拥有 `@on(DataTable.RowSelected)` 注解。当方法接受选中的行后,它会推送一个新的屏幕,显示选中行的详细信息(`class DetailScreen(ModalScreen)`)。
|
||
|
||
现在,我们详细地探讨一下如何显示选手的详细信息。
|
||
|
||
#### 利用多屏展示复杂视图
|
||
|
||
![][20]
|
||
|
||
当用户选择表格中的一行,`on_row_clicked` 方法就会被调用。它收到的是一个 `DataTable.RowSelected` 类型的事件。从这里我们会用选中的行的内容构建一个 `DetailScreen(ModalScreen)` 类的实例:
|
||
|
||
```
|
||
from typing import Any, List
|
||
from textual import on
|
||
from textual.app import ComposeResult
|
||
from textual.screen import ModalScreen
|
||
from textual.widgets import Button, MarkdownViewer
|
||
|
||
MY_DATA = [
|
||
("level", "name", "gender", "country", "age"),
|
||
("Green", "Wai", "M", "MYS", 22),
|
||
("Red", "Ryoji", "M", "JPN", 30),
|
||
("Purple", "Fabio", "M", "ITA", 99),
|
||
("Blue", "Manuela", "F", "VEN", 25)
|
||
]
|
||
|
||
class DetailScreen(ModalScreen):
|
||
ENABLE_COMMAND_PALETTE = False
|
||
CSS_PATH = "details_screen.tcss"
|
||
|
||
def __init__(
|
||
self,
|
||
name: str | None = None,
|
||
ident: str | None = None,
|
||
classes: str | None = None,
|
||
row: List[Any] | None = None,
|
||
):
|
||
super().__init__(name, ident, classes)
|
||
self.row: List[Any] = row
|
||
|
||
def compose(self) -> ComposeResult:
|
||
self.log.info(f"Details: {self.row}")
|
||
columns = MY_DATA[0]
|
||
row_markdown = "\n"
|
||
for i in range(0, len(columns)):
|
||
row_markdown += f"* **{columns[i].title()}:** {self.row[i]}\n"
|
||
yield MarkdownViewer(f"""## User details:
|
||
{row_markdown}
|
||
""")
|
||
button = Button("Close", variant="primary", id="close")
|
||
button.tooltip = "Go back to main screen"
|
||
yield button
|
||
|
||
@on(Button.Pressed, "#close")
|
||
def on_button_pressed(self, _) -> None:
|
||
self.app.pop_screen()
|
||
```
|
||
|
||
这个类的职责很直接:
|
||
|
||
1. `compose` 方法取得此行数据,并利用一个 [支持 Markdown 渲染的组件][21] 来展示内容。它的便利之处在于,它会为我们自动生成一个内容目录。
|
||
2. 当用户点击 “close” 后,方法 `on_button_pressed` 会引导应用回到原始屏幕。注解 `@on(Button.Pressed, "#close")` 用来接收按键被点击的事件。
|
||
|
||
最后,我们来详细讲解一下那个多功能的搜索栏(也叫做命令面板)。
|
||
|
||
#### 命令面板的搜索功能
|
||
|
||
![][22]
|
||
|
||
任何使用了表头的 Textual 应用都默认开启了 [命令面板][19]。有意思的是,你可以在 `CompetitorsApp` 类中添加自定义的命令,这会增加到默认命令集之上:
|
||
|
||
```
|
||
COMMANDS = App.COMMANDS | {CustomCommand}
|
||
```
|
||
|
||
然后是执行大部分任务的 `CustomCommand(Provider)` 类:
|
||
|
||
```
|
||
from functools import partial
|
||
from typing import Any, List
|
||
from rich.style import Style
|
||
from textual.command import Provider, Hit
|
||
from textual.screen import ModalScreen, Screen
|
||
from textual.widgets import DataTable
|
||
from textual.app import App
|
||
|
||
class CustomCommand(Provider):
|
||
|
||
def __init__(self, screen: Screen[Any], match_style: Style | None = None):
|
||
super().__init__(screen, match_style)
|
||
self.table = None
|
||
|
||
async def startup(self) -> None:
|
||
my_app = self.app
|
||
my_app.log.info(f"Loaded provider: CustomCommand")
|
||
self.table = my_app.query(DataTable).first()
|
||
|
||
async def search(self, query: str) -> Hit:
|
||
matcher = self.matcher(query)
|
||
|
||
my_app = self.screen.app
|
||
assert isinstance(my_app, CompetitorsApp)
|
||
|
||
my_app.log.info(f"Got query: {query}")
|
||
for row_key in self.table.rows:
|
||
row = self.table.get_row(row_key)
|
||
my_app.log.info(f"Searching {row}")
|
||
searchable = row[1]
|
||
score = matcher.match(searchable)
|
||
if score > 0:
|
||
runner_detail = DetailScreen(row=row)
|
||
yield Hit(
|
||
score,
|
||
matcher.highlight(f"{searchable}"),
|
||
partial(my_app.show_detail, runner_detail),
|
||
help=f"Show details about {searchable}"
|
||
)
|
||
|
||
class DetailScreen(ModalScreen):
|
||
def __init__(
|
||
self,
|
||
name: str | None = None,
|
||
ident: str | None = None,
|
||
classes: str | None = None,
|
||
row: List[Any] | None = None,
|
||
):
|
||
super().__init__(name, ident, classes)
|
||
# Code of this class explained on the previous section
|
||
|
||
class CompetitorsApp(App):
|
||
# Add the default commands and the TablePopulateProvider to get a row directly by name
|
||
COMMANDS = App.COMMANDS | {CustomCommand}
|
||
# Most of the code shown before, only displaying relevant code
|
||
def show_detail(self, detailScreen: DetailScreen):
|
||
self.push_screen(detailScreen)
|
||
```
|
||
|
||
1. 所有继承自 `Provider` 的类需实现 `search` 方法。在我们的例子中,我们还覆盖了 `startup` 方法,为了获取到我们应用表格(和其内容)的引用,这里使用到了 `App.query(DataTable).first()`。在类的生命周期中, `startup` 方法只会被调用一次。
|
||
2. 在 `search` 方法内,我们使用 `Provider.matcher` 对每个表格行的第二列(即名字)进行模糊搜索,以与用户在 TUI 中输入的词条进行比较。`matcher.match(searchable)` 返回一个整型的评分,大于零说明匹配成功。
|
||
3. 在 `search` 方法中,如果评分大于零,则返回一个 `Hit` 对象,以告知命令面板搜索查询是否成功。
|
||
4. 每个 `Hit` 都有以下信息:评分(用于在命令面板中对匹配项排序)、高亮显示的搜索词、一个可调用对象的引用(在我们的案例中,它是一个可以将表格行推送到新屏幕的函数)。
|
||
5. `Provider` 类的所有方法都是异步的。这使你能释放主线程,只有当响应准备好后才返回结果,这个过程不会冻结用户界面。
|
||
|
||
理解了这些信息,我们就可以现在展示赛手的详细信息了。
|
||
|
||
尽管这个架构的追踪功能相对直观,但是组件间传递的消息复杂性不可忽视。幸运的是,Textual 提供了有效的调试工具帮助我们理解背后的工作原理。
|
||
|
||
### Textual 应用的问题排查
|
||
|
||
对于 Python 的 Textual 应用进行 [调试][23] 相较而言更具挑战性。这是因为其中有一些操作可能是异步的,而在解决组件问题时设置断点可能颇为复杂。
|
||
|
||
根据具体情况,你可以使用一些工具。但首先,确保你已经安装了 textual 的开发工具:
|
||
|
||
```
|
||
pip install textual-dev==1.3.0
|
||
```
|
||
|
||
#### 确保你能捕捉到正确的按键
|
||
|
||
不确定 Textual 应用是否能捕捉到你的按键操作?运行 keys 应用:
|
||
|
||
```
|
||
textual keys
|
||
```
|
||
|
||
这让你能够验证一下你的按键组合,并确认在 Textual 中产生了哪些事件。
|
||
|
||
#### 图片比千言万语更直观
|
||
|
||
如果说你在布局设计上遇到了问题,想向他人展示你当前的困境,Textual 为你的运行应用提供了截图功能:
|
||
|
||
```
|
||
textual run --screenshot 5 ./kodegeek_textualize/log_scroller.py
|
||
```
|
||
|
||
就像你所看到的,我是通过这种方式为这篇教程创建了插图。
|
||
|
||
#### 捕获事件并输出定制消息
|
||
|
||
在 Textual 中,每一个应用实例都有一个日志记录器,可以使用如下方式访问:
|
||
|
||
```
|
||
my_app = self.screen.app
|
||
my_app.log.info(f"Loaded provider: CustomCommand")
|
||
```
|
||
|
||
想要查看这些消息,首先需要开启一个控制台:
|
||
|
||
```
|
||
. ~/virtualenv/Textualize/bin/activate
|
||
textual console
|
||
```
|
||
|
||
然后在另一个终端运行你的应用程序:
|
||
|
||
```
|
||
. ~/virtualenv/Textualize/bin/activate
|
||
textual run --dev ./kodegeek_textualize/log_scroller.py
|
||
```
|
||
|
||
在运行控制台的终端中,你可以看到实时的事件和消息输出:
|
||
|
||
```
|
||
|
||
▌Textual Development Console v0.46.0
|
||
▌Run a Textual app with textual run --dev my_app.py to connect.
|
||
▌Press Ctrl+C to quit.
|
||
─────────────────────────────────────────────────────────────────────────────── Client '127.0.0.1' connected ────────────────────────────────────────────────────────────────────────────────
|
||
[20:29:43] SYSTEM app.py:2188
|
||
Connected to devtools ( ws://127.0.0.1:8081 )
|
||
[20:29:43] SYSTEM app.py:2192
|
||
---
|
||
[20:29:43] SYSTEM app.py:2194
|
||
driver=<class 'textual.drivers.linux_driver.LinuxDriver'>
|
||
[20:29:43] SYSTEM app.py:2195
|
||
loop=<_UnixSelectorEventLoop running=True closed=False debug=False>
|
||
[20:29:43] SYSTEM app.py:2196
|
||
features=frozenset({'debug', 'devtools'})
|
||
[20:29:43] SYSTEM app.py:2228
|
||
STARTED FileMonitor({PosixPath('/home/josevnz/TextualizeTutorial/docs/Textualize/kodegeek_textualize/os_app.tcss')})
|
||
[20:29:43] EVENT
|
||
```
|
||
|
||
此外,以开发者模式运行的另一大好处是,如果你更改了 CSS,应用会尝试重新渲染,而无需重启程序。
|
||
|
||
### 如何编写单元测试
|
||
|
||
为你全新开发的 Textual 应用编写 [单元测试][24],应该如何操作呢?
|
||
|
||
在 [官方文档][25] 展示了几种用于测试我们应用的方式。
|
||
|
||
我将采用 [unittest][24] 进行测试。为了处理异步例程,我们会需要特别的类 `unittest.IsolatedAsyncioTestCase` :
|
||
|
||
```
|
||
import unittest
|
||
from textual.widgets import Log, Button
|
||
from kodegeek_textualize.log_scroller import OsApp
|
||
|
||
class LogScrollerTestCase(unittest.IsolatedAsyncioTestCase):
|
||
async def test_log_scroller(self):
|
||
app = OsApp()
|
||
self.assertIsNotNone(app)
|
||
async with app.run_test() as pilot:
|
||
# Execute the default commands
|
||
await pilot.click(Button)
|
||
await pilot.pause()
|
||
event_log = app.screen.query(Log).first() # We pushed the screen, query nodes from there
|
||
self.assertTrue(event_log.lines)
|
||
await pilot.click("#close") # Close the new screen, pop the original one
|
||
await pilot.press("q") # Quit the app by pressing q
|
||
|
||
|
||
if __name__ == '__main__':
|
||
unittest.main()
|
||
```
|
||
|
||
现在让我们详细看看 `test_log_scroller` 方法中的操作步骤:
|
||
|
||
1. 通过 `app.run_test()` 获取一个 `Pilot` 实例。然后点击主按钮,运行包含默认指令的查询,随后等待所有事件的处理。
|
||
2. 从我们新推送出的屏幕中获取 `Log`,确保我们已获得几行返回的内容,即它并非空的。
|
||
3. 关闭新屏幕并重新呈现旧屏幕。
|
||
4. 最后,按下 `q`,退出应用。
|
||
|
||
可以测试表格吗?
|
||
|
||
```
|
||
import unittest
|
||
from textual.widgets import DataTable, MarkdownViewer
|
||
from kodegeek_textualize.table_with_detail_screen import CompetitorsApp
|
||
|
||
|
||
class TableWithDetailTestCase(unittest.IsolatedAsyncioTestCase):
|
||
async def test_app(self):
|
||
app = CompetitorsApp()
|
||
self.assertIsNotNone(app)
|
||
async with app.run_test() as pilot:
|
||
|
||
"""
|
||
Test the command palette
|
||
"""
|
||
await pilot.press("ctrl+\\")
|
||
for char in "manuela".split():
|
||
await pilot.press(char)
|
||
await pilot.press("enter")
|
||
markdown_viewer = app.screen.query(MarkdownViewer).first()
|
||
self.assertTrue(markdown_viewer.document)
|
||
await pilot.click("#close") # Close the new screen, pop the original one
|
||
|
||
"""
|
||
Test the table
|
||
"""
|
||
table = app.screen.query(DataTable).first()
|
||
coordinate = table.cursor_coordinate
|
||
self.assertTrue(table.is_valid_coordinate(coordinate))
|
||
await pilot.press("enter")
|
||
await pilot.pause()
|
||
markdown_viewer = app.screen.query(MarkdownViewer).first()
|
||
self.assertTrue(markdown_viewer)
|
||
# Quit the app by pressing q
|
||
await pilot.press("q")
|
||
|
||
|
||
if __name__ == '__main__':
|
||
unittest.main()
|
||
```
|
||
|
||
如果你运行所有的测试,你将看到如下类似的输出:
|
||
|
||
```
|
||
(Textualize) [josevnz@dmaf5 Textualize]$ python -m unittest tests/*.py
|
||
..
|
||
----------------------------------------------------------------------
|
||
Ran 2 tests in 2.065s
|
||
|
||
OK
|
||
```
|
||
|
||
这是测试 TUI 的一个不错的方式,对吧?
|
||
|
||
### 打包 Textual 应用
|
||
|
||
打包 Textual 应用与打包常规 Python 应用并没有太大区别。你需要记住,需要包含那些控制应用外观的 CSS 文件:
|
||
|
||
```
|
||
. ~/virtualenv/Textualize/bin/activate
|
||
python -m build
|
||
pip install dist/KodegeekTextualize-*-py3-none-any.whl
|
||
```
|
||
|
||
这个教程的 [pyproject.toml][26] 文件是一个打包应用的良好起点,告诉你需要做什么。
|
||
|
||
```
|
||
[build-system]
|
||
requires = [
|
||
"setuptools >= 67.8.0",
|
||
"wheel>=0.42.0",
|
||
"build>=1.0.3",
|
||
"twine>=4.0.2",
|
||
"textual-dev>=1.2.1"
|
||
]
|
||
build-backend = "setuptools.build_meta"
|
||
|
||
[project]
|
||
name = "KodegeekTextualize"
|
||
version = "0.0.3"
|
||
authors = [
|
||
{name = "Jose Vicente Nunez", email = "kodegeek.com@protonmail.com"},
|
||
]
|
||
description = "Collection of scripts that show how to use several features of textualize"
|
||
readme = "README.md"
|
||
requires-python = ">=3.9"
|
||
keywords = ["running", "race"]
|
||
classifiers = [
|
||
"Environment :: Console",
|
||
"Development Status :: 4 - Beta",
|
||
"Programming Language :: Python :: 3",
|
||
"Intended Audience :: End Users/Desktop",
|
||
"Topic :: Utilities"
|
||
]
|
||
dynamic = ["dependencies"]
|
||
|
||
[project.scripts]
|
||
log_scroller = "kodegeek_textualize.log_scroller:main"
|
||
table_detail = "kodegeek_textualize.table_with_detail_screen:main"
|
||
|
||
[tool.setuptools]
|
||
include-package-data = true
|
||
|
||
[tool.setuptools.packages.find]
|
||
where = ["."]
|
||
exclude = ["test*"]
|
||
|
||
[tool.setuptools.package-data]
|
||
kodegeek_textualize = ["*.txt", "*.tcss", "*.csv"]
|
||
img = ["*.svg"]
|
||
|
||
[tool.setuptools.dynamic]
|
||
dependencies = {file = ["requirements.txt"]}
|
||
```
|
||
|
||
### 未来计划
|
||
|
||
这个简短的教程只覆盖了 Textual 的部分方面。还有很多需要探索和学习的内容:
|
||
|
||
* 强烈建议你查看 [官方教程][27]。有大量的示例和指向参考 [API][28] 的链接。
|
||
* Textual 可以使用来自 [Rich][29] 项目的组件,这个项目是一切的起源。我认为其中一些甚至可能所有这些组件在某些时候都会合并到 Textual 中。Textual 框架对于使用高级 API 的复杂应用更能胜任,但 Rich 也有很多漂亮的功能。
|
||
* 创建你自己的组件!同样,在设计 TUI 时,[拿一张纸,画出你希望这些组件如何布局的][30],这会为你后期省去很多时间和麻烦。
|
||
* 调试 Python 应用可能会有点复杂。有时你可能需要 [混合使用不同的工具][31] 来找出应用的问题所在。
|
||
* 异步 IO 是一个复杂的话题,你应该 [阅读开发者文档][32] 来了解更多可能的选择。
|
||
* Textual 被其他项目所使用。其中一个非常易于使用的项目是 [Trogon][33]。[它会让你的 CLI 可以自我发现][34]。
|
||
* [Textual-web][35] 是个很有前景的项目,能让你在浏览器上运行 Textual 应用。尽管它不如 Textual 成熟,但它的进化速度非常快。
|
||
* 最后,[查看这些外部项目][36]。在项目组合中有许多有用的开源应用。
|
||
|
||
*(题图:DA/f11b0eb0-8e16-4cbe-986a-0fe978f6732a)*
|
||
|
||
--------------------------------------------------------------------------------
|
||
|
||
via: https://fedoramagazine.org/crash-course-on-using-textual/
|
||
|
||
作者:[Jose Nunez][a]
|
||
选题:[lujun9972][b]
|
||
译者:[ChatGPT](https://linux.cn/lctt/ChatGPT)
|
||
校对:[wxy](https://github.com/wxy)
|
||
|
||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译,[Linux中国](https://linux.cn/) 荣誉推出
|
||
|
||
[a]: https://fedoramagazine.org/author/josevnz/
|
||
[b]: https://github.com/lujun9972
|
||
[1]: https://fedoramagazine.org/wp-content/uploads/2024/01/textual_course-816x345.jpg
|
||
[2]: https://unsplash.com/@bernardhermant?utm_content=creditCopyText&utm_medium=referral&utm_source=unsplash
|
||
[3]: https://unsplash.com/photos/gray-and-clear-digital-wallpaper-VUBAE-Bmugk?utm_content=creditCopyText&utm_medium=referral&utm_source=unsplash
|
||
[4]: https://docs.python.org/3/library/tkinter.html
|
||
[5]: https://textual.textualize.io/
|
||
[6]: https://tutorials.kodegeek.com/Textualize/img/output_of_multiple_well_known_unix_commands_2023-12-28T19_13_32_605621.svg
|
||
[7]: https://manpages.org/bash
|
||
[8]: https://textual.textualize.io/tutorial/#composing-the-widgets
|
||
[9]: https://textual.textualize.io/widget_gallery/
|
||
[10]: https://textual.textualize.io/api/binding/
|
||
[11]: https://textual.textualize.io/guide/screens/
|
||
[12]: https://textual.textualize.io/guide/styles/
|
||
[13]: https://tutorials.kodegeek.com/Textualize/img/output_of_multiple_well_known_unix_commands_2023-12-28T19_13_40_503695.svg
|
||
[14]: https://docs.python.org/3/library/asyncio.html
|
||
[15]: https://textual.textualize.io/guide/workers/
|
||
[16]: https://tutorials.kodegeek.com/Textualize/img/summary_2023-12-28T19_05_20_213933.svg
|
||
[17]: https://textual.textualize.io/widgets/header/
|
||
[18]: https://textual.textualize.io/widgets/data_table/#guide
|
||
[19]: https://textual.textualize.io/guide/command_palette/
|
||
[20]: https://tutorials.kodegeek.com/Textualize/img/summary_2023-12-28T19_05_44_404837.svg
|
||
[21]: https://textual.textualize.io/widget_gallery/#markdownviewer
|
||
[22]: https://tutorials.kodegeek.com/Textualize/img/summary_2023-12-28T19_05_55_822030.svg
|
||
[23]: https://github.com/josevnz/tutorials/blob/main/docs/PythonDebugger/README.md
|
||
[24]: https://docs.python.org/3/library/unittest.html
|
||
[25]: https://textual.textualize.io/guide/testing/
|
||
[26]: https://tutorials.kodegeek.com/Textualize/pyproject.toml
|
||
[27]: https://textual.textualize.io/tutorial/
|
||
[28]: https://textual.textualize.io/api/
|
||
[29]: https://github.com/Textualize/rich
|
||
[30]: https://textual.textualize.io/how-to/design-a-layout/
|
||
[31]: https://github.com/josevnz/DebuggingApplications/blob/main/StracePythonWireshark/README.md
|
||
[32]: https://docs.python.org/3/library/asyncio-dev.html
|
||
[33]: https://github.com/Textualize/trogon
|
||
[34]: https://github.com/josevnz/CLIWithClickAndTrogon/blob/main/README.md
|
||
[35]: https://github.com/Textualize/textual-web
|
||
[36]: https://www.textualize.io/projects/
|
||
[37]: https://github.com/josevnz
|
||
[0]: https://img.linux.net.cn/data/attachment/album/202401/15/110359fptrxpqffztniz45.jpg |