Let’s step through this methodically to understand when the __init__ method is called and why, and then delve into the concept of a __metaclass__ with an explanation and code examples.
Understanding __init__ in the context of a Metaclass
The __init__ method in a class is called when an instance of that class is created. However, in the context of a metaclass, the situation is a bit different. A metaclass in Python is a class of a class that defines how a class behaves. A metaclass has its own __init__ method, which is called when a class (not an instance) is created. This means that when you define a new class using a metaclass, the metaclass’s __init__ method will be called to initialize the new class, not an instance of it.
In your code example, Register is defined as a metaclass because it inherits from type, which is the built-in metaclass Python uses for all new-style classes.
Here’s what happens step by step:
Simple Code Example
When you run this code, you’ll see that the fully qualified name of Metanode is printed. This confirms that the metaclass’s __init__ was indeed called during the creation of Metanode.
Understanding and Explaining __metaclass__
A __metaclass__ attribute in a class definition allows you to specify the metaclass for that class. The specified metaclass will affect how the class is created and can control various aspects of its behavior by defining methods like __new__(), which allocates memory for the new object, and __init__(), which initializes it.
Code Example Demonstrating __metaclass__
In this example, we’ve defined a new metaclass named VerboseMeta. As soon as we use this metaclass to create another base class (BaseClass), it prints out a message indicating that it’s creating a new class. It does this also when subclassing from BaseClass (as seen with SubClass). This demonstrates how a metaclass can take control over class creation.
Original Post can be find in the link below, I paste here in case it can not be access in the future.
Quote from JoDaRober
If you have issues with the dialog not appearing at the center of the screen, you can center it when showing the UI. I prefer to override QDialog’s show method for this, since it will have to happen after any widget creation that can change the dimensions of the dialog, and that include’s QtDialog’s show() method. Here’s an example:
If you only want to zero out all selecting objects:
Then we have to pass two arguments for the .bat file
In a different circumstance when you want to back trace the parent folder
Or if it is intended to exclude some of the objects by name
Can use the following method as rule:
Need to work with the Timeline system
This Script should be attach to the main Camera
// make sure you add this to enable the Unity Postprocessing library
public class VignettePulse : MonoBehaviour
//name the Script the Way you want
//A customized PostProcessVolume and its profile
// A customized instance of the profile and its settings
m_Vignette = ScriptableObject.CreateInstance<Vignette>();
//Name the setting, attach it with a temp scriptable game object
m_Volume = PostProcessManager.instance.QuickVolume(gameObject.layer, 100f, m_Vignette);
// Assign this to the volume, make sure you got the layer correct. Currently it will read the layer of the game object it is attaching.
m_Vignette.intensity.value = Mathf.Sin(Time.realtimeSinceStartup);