3

我正在尝试在 Maya 中编写一个用户界面，并且它与多层次的父母和没有缩进变得令人难以置信的混乱。基本代码（没有任何功能）目前大约 400 行，需要一段时间才能找到我需要的位。

例如，下面的代码没有注释：

#Earlier user interface

py.rowColumnLayout( numberOfColumns = 5 )
py.text( label="", width = 1 )
py.text( label="Column 1", enable = False, width = 250 )
py.text( label="", width = 1 )
py.text( label="Column 2" enable = False, width = 250 )
py.text( label="", width = 1 )

py.text( label="" )
py.rowColumnLayout( numberOfColumns = 4 )
py.text( label="   Input data:", align="left" )
py.text( label="" )
py.text( label="" )
py.text( label="" )
py.textField( text = "Text here" )
py.text( label="" )
py.text( label="" )
py.text( label="" )
py.setParent( ".." )

py.text( label="" )
py.rowColumnLayout( numberOfColumns = 4 )
py.rowColumnLayout( numberOfColumns = 5 )
py.radioButton( label = "Read file from path", width = 100 )
py.text( label="" )
py.button( label = "Browse" )
py.text( label="" )
py.button( label = "Validate" )
py.setParent( ".." )
py.text( label="" )
py.text( label="" )
py.text( label="" )
py.setParent( ".." )
py.setParent( ".." )

然而，这就是缩进的样子

py.rowColumnLayout( numberOfColumns = 5 )
    py.text( label="", width = 1 )
    py.text( label="Column 1", enable = False, width = 250 )
    py.text( label="", width = 1 )
    py.text( label="Column 2" enable = False, width = 250 )
    py.text( label="", width = 1 )

    py.text( label="" )
    py.rowColumnLayout( numberOfColumns = 4 )
        py.text( label="   Input data:", align="left" )
        py.text( label="" )
        py.text( label="" )
        py.text( label="" )
        py.textField( text = "Text here" )
        py.text( label="" )
        py.text( label="" )
        py.text( label="" )
        py.setParent( ".." )

    py.text( label="" )
    py.rowColumnLayout( numberOfColumns = 4 )
        py.rowColumnLayout( numberOfColumns = 5 )
            py.radioButton( label = "Read file from path", width = 100 )
            py.text( label="" )
            py.button( label = "Browse" )
            py.text( label="" )
            py.button( label = "Validate" )
            py.setParent( ".." )
        py.text( label="" )
        py.text( label="" )
        py.text( label="" )
        py.setParent( ".." )
    py.setParent( ".." )

有什么办法我可以用缩进写它，但让它在执行时忽略它们？我看到了一个问题，询问您是否可以在没有缩进的情况下编写 python，但我有点需要相反的情况。

注意：一些py.*函数的输出值也需要分配给变量，只是还没有分配，因为布局需要首先排序。

4

7 回答 7

7

这是像我们这样的技术艺术家在 Maya 中构建 UI 时每天都面临的一个极好的用例。

对于基于 PyMEL 的用户界面：

这内置于 PyMEL 中。您不必创建上下文管理器。布局命令本身就是上下文管理器。您只需with在每个布局命令调用之前添加一个关键字，如下所示：

# Do this when using PyMEL for your UI code
import pymel.core as pm

# ...

with pm.rowColumnLayout( numberOfColumns = 5 ):
    pm.text( label="", width = 1 )
    pm.text( label="Column 1", enable = False, width = 250 )
    pm.text( label="", width = 1 )
    pm.text( label="Column 2", enable = False, width = 250 )
    pm.text( label="", width = 1 )

    pm.text( label="" )

    with pm.rowColumnLayout( numberOfColumns = 4 ):
        pm.text( label="   Input data:", align="left" )
        pm.text( label="" )
        pm.text( label="" )
        pm.text( label="" )
        pm.textField( text = "Text here" )
        pm.text( label="" )
        pm.text( label="" )
        pm.text( label="" )        

    pm.text( label="" )
    with pm.rowColumnLayout( numberOfColumns = 4 ):
        with pm.rowColumnLayout( numberOfColumns = 5 ):
            pm.radioButton( label = "Read file from path", width = 100 )
            pm.text( label="" )
            pm.button( label = "Browse" )
            pm.text( label="" )
            pm.button( label = "Validate" )

        pm.text( label="" )
        pm.text( label="" )
        pm.text( label="" )

对于基于 maya.cmds 的 UI：

一种快速的解决方案是制作一个虚拟上下文管理器。你可以做这样的事情

# Do this when using Maya's cmds for your UI code
import maya.cmds as cmds

# ...

from contextlib import contextmanager
@contextmanager
def neat_indent():
    # OPTIONAL: This is also an opportunity to do something before the block of code runs!
    try:
        # During this is where your indented block will execute
        # Leave it empty
        yield
    finally:
        # OPTIONAL: This is where you can write code that executes AFTER your indented block executes.
        pass

这样您的代码就不必更改太多。只需with在每个预期缩进的开头添加带有关键字的上下文管理器功能！

cmds.rowColumnLayout( numberOfColumns = 5 )
with neat_indent():
    cmds.text( label="", width = 1 )
    cmds.text( label="Column 1", enable = False, width = 250 )
    cmds.text( label="", width = 1 )
    cmds.text( label="Column 2", enable = False, width = 250 )
    cmds.text( label="", width = 1 )

    cmds.text( label="" )

    cmds.rowColumnLayout( numberOfColumns = 4 )
    with neat_indent():
        cmds.text( label="   Input data:", align="left" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.textField( text = "Text here" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.setParent( ".." )

    cmds.text( label="" )
    cmds.rowColumnLayout( numberOfColumns = 4 )
    with neat_indent():
        cmds.rowColumnLayout( numberOfColumns = 5 )
        with neat_indent():
            cmds.radioButton( label = "Read file from path", width = 100 )
            cmds.text( label="" )
            cmds.button( label = "Browse" )
            cmds.text( label="" )
            cmds.button( label = "Validate" )
            cmds.setParent( ".." )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.setParent( ".." )
    cmds.setParent( ".." )

我们创建的上下文管理器neat_indent()，还让您有机会编写包装缩进块的代码。这里的一个实际例子是，在每个缩进的末尾，你发现自己在写py.setParent("..")。您可以将其放入finally上下文管理器的部分：

from contextlib import contextmanager
@contextmanager
def neat_indent(parent=None):
    # OPTIONAL: This is also an opportunity to do something before the block of code runs!
    try:
        # During this is where your indented block will execute
        # Leave it empty
        yield
    finally:
        # OPTIONAL: This is where you can write code that executes AFTER your indented block executes.
        if parent:
            cmds.setParent(parent)

您的代码现在将更有意义：

cmds.rowColumnLayout( numberOfColumns = 5 )
with neat_indent(".."):
    cmds.text( label="", width = 1 )
    cmds.text( label="Column 1", enable = False, width = 250 )
    cmds.text( label="", width = 1 )
    cmds.text( label="Column 2", enable = False, width = 250 )
    cmds.text( label="", width = 1 )

    cmds.text( label="" )

    cmds.rowColumnLayout( numberOfColumns = 4 )
    with neat_indent(".."):
        cmds.text( label="   Input data:", align="left" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.textField( text = "Text here" )
        cmds.text( label="" )
        cmds.text( label="" )
        cmds.text( label="" )        

    cmds.text( label="" )
    cmds.rowColumnLayout( numberOfColumns = 4 )
    with neat_indent(".."):
        cmds.rowColumnLayout( numberOfColumns = 5 )
        with neat_indent(".."):
            cmds.radioButton( label = "Read file from path", width = 100 )
            cmds.text( label="" )
            cmds.button( label = "Browse" )
            cmds.text( label="" )
            cmds.button( label = "Validate" )

        cmds.text( label="" )
        cmds.text( label="" )
        cmds.text( label="" )

上下文管理器很强大。在这篇文章中，我使用了标准库模块中的contextmanager 装饰器。您可以在此处contextlib阅读有关此技术的信息。大概在这里。with

此外，出于这个目的（目的之一），在 Maya 中进行 UI 开发更清洁、更 Pythonic，@theodox 创建了mGui模块。一探究竟。

于 2015-01-19T21:56:00.917 回答
1

@Kartik 的回答很好地涵盖了基础。我要指出的是，您可以通过允许上下文管理器内联声明布局（rowLayout、columnLayout 等）来进一步清理布局代码，这使得它更加容易：

class uiCtx(object):
   '''
   quickie layouthelper: automatically setParents after a layout is finished
   '''
   def __init__(self, uiClass, *args, **kwargs):
        self.Control = uiClass(*args, **kwargs)

    def __enter__(self):
        return self

    def __exit__(self, tb, val, traceback):
        cmds.setParent("..")

    def __repr__(self):
        return self.Control

遇到它时将调用 maya.cmds 布局函数，然后在缩进块的末尾关闭父级，因此您可以在此代码段中随时进行布局调用

    with uiCtx(cmds.rowLayout, **layout_options) as widget:
        self.Toggle = cmds.checkBox('', v = self.Module.enabled, cc = self._state_changed)
        with uiCtx(cmds.columnLayout, w=self.COLUMNS[1], cal='left') as details:
            cmds.text(l = self.ModuleKey, fn = "boldLabelFont")
            cmds.text(l = self.Module.path, fn = "smallObliqueLabelFont")
        cmds.button("edit",  c=self._edit)
        cmds.button("show", c=self._show)
    return widget

向 中添加__repr__可以uiCtx让您将其视为像普通 Maya 布局命令那样返回字符串，因此在该示例中可以以通常的方式查询“小部件”。

整个事情都在 GitHub 上，以便在上下文中查看它。正如 Kartik 还指出的那样，有一个更精细的声明性 UI 选项，形式为mGui，在实践中看起来像这样：

with gui.Window('window', title = 'fred') as example_window:
    with BindingContext() as bind_ctx:
        with VerticalForm('main') as main:
            Text(None, label = "The following items don't have vertex colors")
            lists.VerticalList('lister' ).Collection < bind() < bound  
            with HorizontalStretchForm('buttons'):
                Button('refresh', l='Refresh')
                Button('close', l='Close')

# show the window
example_window.show()

这里有更多与 Maya 布局相关的信息

于 2015-01-20T20:28:31.313 回答
1

您可以在执行代码行之前对其进行预处理，如图所示：

mycode = """\
    print "something"
        print "something else"
      print 42
    """

exec('\n'.join(line.lstrip() for line in mycode.splitlines()))

输出：

something
something else
42

它甚至可以做成“单线”：

exec('\n'.join(line.lstrip() for line in """\
    print "something"
        print "something else"
      print 42
    """.splitlines()))

您可以通过以下方式将代码保存在一个单独的文件中（这将使您的编辑器能够对其进行语法照明）：

文件mycode.py：

print "something"
    print "something else"
  var = 42

单独文件版本：

with open('mycode.py') as code:
    exec(''.join(line.lstrip() for line in code))
print 'var:', var

输出：

something
something else
var: 42

警告：我应该指出，这些都删除了每一行的所有缩进，这会弄乱if/else遇到的任何多行 Python 代码（如 ）——这可能会限制它的有用性，具体取决于你在做什么。

于 2015-01-19T18:48:34.283 回答
0

创建另一个程序来解析和执行您的script.py：

parse.py

text = open('script.py').readlines()
text = [i.strip() for i in text]

edit = open('new.py', 'w')
for line in text:
    edit.write(line + '\n')
edit.close()

execfile('new.py')

该文件创建一个new.py将被执行的修改。

于 2015-01-19T18:41:01.897 回答
0

我可以想到两种可能性，允许您直接编写代码而不必从文本中解析它（语法着色完整，没有临时文件）。

第一个是在每一行的开头加上一个不言而喻的前缀，就像if True:上面建议的那样，或者等效地，可能是这样的：

# ...

if 'level 1':  a = py.text( label="" )
if 'level 2':      b = py.rowColumnLayout( numberOfColumns = 4 )
if 'level 3':          c = py.rowColumnLayout( numberOfColumns = 5 )
if 'level 4':              d = py.radioButton( label = "Read file from path", width = 100 )

# ...

如果您不使用计算结果为False(like '') 的字符串，您可以将这些字符串用作注释，以帮助您记住您在任何给定行上构建的 GUI 的哪个部分（用适当数量的空格填充以确保事情当然，仍然排队）。

第二个想法是创建一个包含可调用对象及其参数的容器列表，按照您喜欢的方式格式化该列表，并在最后执行每个：

objects = {}
commands = [

    # ...

    dict( name = 'spam', func = py.text, label="" ),
    dict( name = 'ham', func = py.rowColumnLayout, numberOfColumns = 4 ),
        dict( name = 'eggs', func = py.rowColumnLayout, numberOfColumns = 5 ),
            dict( name = 'beans', func = py.radioButton, label = "Read file from path", width = 100 ),

    # ...
]

for d in commands:
    objects[ d.pop( 'name' ) ] = d.pop( 'func' )( **d )
于 2015-01-19T18:50:07.407 回答
0

使用声明性方法：

interface = [
  [py.rowColumnLayout, [], dict(numberOfColumns=5)],
     [py.text, [], dict(label="", width=1)],
     [py.text, [], dict(label="Column 1", enable=False, width=250)],
     ...
     [py.setParent, [".."], {}],
]    

for callable, args, kwargs in interface:
    callable(*args, **kwargs)

内部()或[]缩进无关紧要，因此您可以随意组织线条。

于 2015-01-19T20:33:33.290 回答
0

我已经使用了很多年了，效果很好：

if True:
    # Indented code.
    print("This entire code block is indented.")
于 2021-08-18T10:30:31.843 回答