Question

为了更好地了解类的调用方式和工作方式，我一直在尝试编写一些简单的脚本来为我工作的一些功能，这些脚本可以在Maya的3D空间中将一个对象捕捉到另一个对象。

当我将它们放在类中并尝试运行代码时，收到的错误消息是：

错误：NameError：文件第10行：全局名称'runSelected'未定义＃

我认为这可能是因为我正在调用前面没有self.的方法。我尝试这样做，但仍然收到错误：

错误：NameError：文件行35：全局名称“ self”为未定义＃

在maya的3D空间中选择两个对象后运行脚本，并通过运行开始：

Align()

该类的代码如下：

#Class for snapping one object to another in Maya.

import maya.cmds as mc


class Align(object):

    def __init__(self):
        #starts the runSelected Method
        self.runSelected()       

    def selectionCheck(mySel):
        #checks that 2 ojects are created, returns True if so, Flase if not.
        if len(mySel) == 2:   
           print "Great! Two selected"  
           return True

        elif len(mySel) == 0: 
           print "Nothing Selected to constrain!"
           return False   

    def createWindow():
        #This creates a simple dialogue window that gives a message.
        mc.confirmDialog(title='Align Objects', m ="Instructions: You need to select two objects to constrain.")

    def runConstrainDelete(mySel):
        #Creates a parent constraint, does not maintain offset and then deletes the constraint when object is moved.Clears selection.
        myParentConstraint = mc.parentConstraint(mySel[0], mySel[1], mo=False)
        mc.delete(myParentConstraint)
        mc.select (clear=True)

    def runSelected(object):
        #Creates a list of objects selected. Runs selection check
        mySel = mc.ls(sl =True)
        result_Sel_Check = self.selectionCheck(mySel)

        #if statement handles if a warning window or the rest of the script should be run.
        if result_Sel_Check == False:
            self.createWindow()    
        else:
            self.runConstrainDelete(mySel)


test_Align = Align()

Answer 1

定义实例方法时，您需要显式传递self作为方法的第一个参数。例如def runSelected(object): 应该更改为def runSelected(self, object):，只有这样才能在方法主体中访问self。您应该阅读python self和实例方法以获得一些直觉。

Answer 2

在创建类时，必须将self作为其中每个函数的第一个参数（除非您尝试使用类或静态方法）。 This has a pretty good explanation关于如何在类中使用self。

您还忘记了在self.runSelected中的__init__上传递参数！

这似乎按预期工作：

#Class for snapping one object to another in Maya.

import maya.cmds as mc


class Align(object):

    def __init__(self):
        #starts the runSelected Method
        self.runSelected(cmds.ls(sl=True))  # Forgot to pass a parameter here.       

    def selectionCheck(self, mySel):
        #checks that 2 ojects are created, returns True if so, Flase if not.
        if len(mySel) == 2:   
           print "Great! Two selected"  
           return True

        elif len(mySel) == 0: 
           print "Nothing Selected to constrain!"
           return False   

    def createWindow(self):
        #This creates a simple dialogue window that gives a message.
        mc.confirmDialog(title='Align Objects', m ="Instructions: You need to select two objects to constrain.")

    def runConstrainDelete(self, mySel):
        #Creates a parent constraint, does not maintain offset and then deletes the constraint when object is moved.Clears selection.
        myParentConstraint = mc.parentConstraint(mySel[0], mySel[1], mo=False)
        mc.delete(myParentConstraint)
        mc.select (clear=True)

    def runSelected(self, object):
        #Creates a list of objects selected. Runs selection check
        mySel = mc.ls(sl =True)
        result_Sel_Check = self.selectionCheck(mySel)

        #if statement handles if a warning window or the rest of the script should be run.
        if result_Sel_Check == False:
            self.createWindow()    
        else:
            self.runConstrainDelete(mySel)


test_Align = Align()

如果使用的是Maya 2016及更高版本，则可以使用cmds.matchTransform来对齐对象。它还将考虑偏移枢轴。否则，您可以使用cmds.xform来对齐对象。尝试避免创建父约束以使其对齐，因为这会降低性能，然后您不得不担心清理场景。

Answer 3

每个使用self的类方法必须在参数列表中具有 self 。其他诸如createWindow，runConstrainDelete和selectionCheck之类的对象应为静态方法（或在类外部定义）。

如何在Maya脚本的Python简单类中修复未定义的方法？

3 个答案: