Class ComponentItem

SLiCAP/schematic/component_item.py:466–841

A single placed component on the schematic canvas. symbol_name : key into the symbol library (e.g. "resistor") instance_id : unique label on this schematic (e.g. "R1") prop_display maps each property key to (show_value, show_name): show_value=False → no label for

class ComponentItem(_ViewBoxSvgItem):
    """
    A single placed component on the schematic canvas.

    symbol_name  : key into the symbol library (e.g. "resistor")
    instance_id  : unique label on this schematic (e.g. "R1")

    prop_display maps each property key to (show_value, show_name):
      show_value=False          → no label for this property
      show_value=True, show_name=False  → displays the value only  (e.g. "1k")
      show_value=True, show_name=True   → displays "name: value"   (e.g. "value: 1k")
    """

    def __init__(self, symbol_name: str, instance_id: str, svg_bytes: bytes):
        stripped, texts = _split_symbol_text(svg_bytes)
        super().__init__(stripped)
        self.symbol_name  = symbol_name
        self.instance_id  = instance_id
        self._svg_bytes   = stripped
        # Embedded symbol text, drawn upright in paint()/export (not in the artwork).
        self.symbol_texts = texts
        self.model: str   = SYMBOL_MODEL.get(symbol_name, "")
        self.params: dict[str, str]  = params_for_symbol(symbol_name) or fixed_params_for_symbol(symbol_name)
        _n_refs = refs_for_symbol(symbol_name)
        _is_sub = SYMBOL_PREFIX.get(symbol_name) == "X"
        self.refs: list[str] = [] if _is_sub else ["?"] * _n_refs
        # Ground and port are power symbols — show net name, never refdes
        _show_refdes = symbol_name not in ("0", "port")
        self.prop_display: dict[str, tuple[bool, bool]] = {"refdes": (_show_refdes, False)}
        # Parameter default visibility comes from the symbol's data-params.
        _param_disp = SYMBOL_PARAM_DISPLAY.get(symbol_name, {})
        for pname in self.params:
            self.prop_display[pname] = _param_disp.get(pname, (False, False))
        # References are shown by default.
        for i in range(refs_for_symbol(symbol_name)):
            self.prop_display[f"ref {i + 1}"] = (True, False)
        # The model is shown per the symbol's data-model flag (subcircuit blocks
        # and "?" reminders set it, e.g. data-model="?|1").
        if self.model:
            self.prop_display["model"] = (SYMBOL_MODEL_SHOW.get(symbol_name, False), False)
        # Power symbols (ground/port) carry a net-name field, shown by default.
        if symbol_name in ("0", "port"):
            self.prop_display["name"] = (True, False)
        self.prop_offsets: dict[str, tuple[float, float]] = {}
        self.h_flip: bool = False
        self.v_flip: bool = False
        self._labels: dict[str, _PropertyLabel] = {}
        # Key of the label the user last clicked, or None.  Drives the dashed
        # leader line: a clicked attribute shows only its own line; selecting the
        # component body (no active label) shows lines to all attributes.
        self._active_label_key: "str | None" = None
        self.setFlag(QGraphicsItem.ItemIsSelectable)
        self.setFlag(QGraphicsItem.ItemIsMovable)
        self.setFlag(QGraphicsItem.ItemSendsGeometryChanges)
        self.setZValue(config.Z_COMPONENT)   # above wires so labels stay selectable
        self._prev_pos: "QPointF | None" = None
        # Wires captured at the start of a drag (as [(wire, point_index), …]) so
        # they follow this component's pins. None until the first move of a drag;