Container.py

from PySide6.QtGui import QFont
from PySide6.QtWidgets import QWidget, QLabel, QHBoxLayout, QSizePolicy, QStackedLayout, QSpacerItem, QVBoxLayout


class Header(QWidget):
    """Header class for collapsible group"""

    def __init__(self, name, content_widget):
        """Header Class Constructor to initialize the object.

        Args:
            name (str): Name for the header
            content_widget (QtWidgets.QWidget): Widget containing child elements
        """
        super(Header, self).__init__()
        self.content = content_widget
        self.expand_ico = ">"   # Use text instead of image
        self.collapse_ico = "v"   # Use text instead of image
        self.setSizePolicy(QSizePolicy.Expanding,
                           QSizePolicy.Fixed)

        # Create a stacked layout to hold the background and widget
        stacked = QStackedLayout(self)
        stacked.setStackingMode(QStackedLayout.StackAll)
        # Create a background label with a specific style sheet
        background = QLabel()
        background.setStyleSheet(
            "QLabel{ background-color: rgb(93, 93, 93); padding-top: -20px; border-radius:2px}")

        # Create a widget and a layout to hold the icon and label
        widget = QWidget()
        layout = QHBoxLayout(widget)

        # Create an icon label and set its text and style sheet
        self.icon = QLabel()
        self.icon.setText(self.expand_ico)
        self.icon.setStyleSheet(
            "QLabel { font-weight: bold; font-size: 20px; color: #000000 }")
        layout.addWidget(self.icon)

        # Add the icon and the label to the layout and set margins
        layout.addWidget(self.icon)
        layout.addWidget(self.icon)
        layout.setContentsMargins(11, 0, 11, 0)

        # Create a font and a label for the header name
        font = QFont()
        font.setBold(True)
        label = QLabel(name)
        label.setStyleSheet("QLabel { margin-top: 5px; }")
        label.setFont(font)

        # Add the label to the layout and add a spacer for expanding
        layout.addWidget(label)
        layout.addItem(QSpacerItem(
            0, 0, QSizePolicy.Expanding, QSizePolicy.Expanding))

        # Add the widget and the background to the stacked layout
        stacked.addWidget(widget)
        stacked.addWidget(background)
        # Set the minimum height of the background based on the layout height
        background.setMinimumHeight(layout.sizeHint().height() * 1.5)

    def mousePressEvent(self, *args):
        """Handle mouse events, call the function to toggle groups"""
        # Toggle between expand and collapse based on the visibility of the content widget
        self.expand() if not self.content.isVisible() else self.collapse()

    def expand(self):
        """Expand the collapsible group"""
        self.content.setVisible(True)
        self.icon.setText(self.collapse_ico)  # Set text instead of pixmap

    def collapse(self):
        """Collapse the collapsible group"""
        self.content.setVisible(False)
        self.icon.setText(self.expand_ico)


class Container(QWidget):
    """Class for creating a collapsible group similar to how it is implement in Maya

        Examples:
            Simple example of how to add a Container to a QVBoxLayout and attach a QGridLayout

            >>> layout = QtWidgets.QVBoxLayout()
            >>> container = Container("Group")
            >>> layout.addWidget(container)
            >>> content_layout = QtWidgets.QGridLayout(container.contentWidget)
            >>> content_layout.addWidget(QtWidgets.QPushButton("Button"))
    """

    def __init__(self, name, color_background=False):
            """Container Class Constructor to initialize the object
    
            Args:
                name (str): Name for the header
                color_background (bool): whether or not to color the background lighter like in maya
            """
            super(Container, self).__init__() # Call the constructor of the parent class
    
            layout = QVBoxLayout(self) # Create a QVBoxLayout instance and pass the current object as the parent
            layout.setContentsMargins(0, 0, 0, 0) # Set the margins of the layout to 0
    
            self._content_widget = QWidget() # Create a QWidget instance and assign it to the instance variable _content_widget
    
            if color_background:
                # If color_background is True, set the stylesheet of _content_widget to have a lighter background color
                self._content_widget.setStyleSheet(".QWidget{background-color: rgb(73, 73, 73); "
                                                   "margin-left: 2px; padding-top: 20px; margin-right: 2px}")
    
            header = Header(name, self._content_widget) # Create a Header instance and pass the name and _content_widget as arguments
            layout.addWidget(header) # Add the header to the layout
            layout.addWidget(self._content_widget) # Add the _content_widget to the layout
    
            # assign header methods to instance attributes so they can be called outside of this class
            self.collapse = header.collapse # Assign the collapse method of the header to the instance attribute collapse
            self.expand = header.expand # Assign the expand method of the header to the instance attribute expand
            self.toggle = header.mousePressEvent # Assign the mousePressEvent method of the header to the instance attribute toggle
    
    @property
    def contentWidget(self):
            """Getter for the content widget
    
            Returns: Content widget
            """
            return self._content_widget # Return the _content_widget when the contentWidget property is accessed