custom_plot_widget.py

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Constants

Name	Value
LINE_STYLE_MAP	{'Solid': Qt.SolidLine, 'Dash': Qt.DashLine, 'D...
LINE_STYLE_REVERSE	{v: k for k, v in LINE_STYLE_MAP.items()}
SCATTER_SYMBOLS	{'Circle': 'o', 'Square': 's', 'Triangle Up': '...
SCATTER_SYMBOLS_REVERSE	{v: k for k, v in SCATTER_SYMBOLS.items()}

Classes

TraceEditorDialog (extends QDialog)

Edit a single trace: color, width, line style, legend name.

Method	Signature	Description
__init__	(self, curve_item, plot_widget, parent = None)	Args:
_setup_ui	(self)
_refresh_color_btn	(self)
_pick_color	(self)
_apply	(self)

ScatterEditorDialog (extends QDialog)

Edit scatter points: fill color, symbol shape, size.

Method	Signature	Description
__init__	(self, scatter_item, plot_widget, parent = None)	Args:
_setup_ui	(self)
_pick_color	(self)
_apply	(self)

AxisLabelEditorDialog (extends QDialog)

Edit an axis label: text, units, font, size, bold/italic, color.

Method	Signature	Description
__init__	(self, plot_widget, axis_name, parent = None)	Args:
_setup_ui	(self)
_pick_color	(self)
_apply	(self)

TitleEditorDialog (extends QDialog)

Edit the plot title.

Method	Signature	Description
__init__	(self, plot_widget, parent = None)	Args:
_setup_ui	(self)
_pick_color	(self)
_apply	(self)

LegendEditorDialog (extends QDialog)

Edit legend appearance.

Method	Signature	Description
__init__	(self, plot_widget, parent = None)	Args:
_setup_ui	(self)
_pick_color	(self)
_apply	(self)

BackgroundEditorDialog (extends QDialog)

Edit background color and grid.

Method	Signature	Description
__init__	(self, plot_widget, parent = None)	Args:
_setup_ui	(self)
_pick_bg	(self)
_apply	(self)

PlotSettingsDialog (extends QDialog)

Method	Signature	Description
__init__	(self, plot_widget, parent = None)	Args:
_setup_ui	(self)
_create_font_tab	(self)
_create_grid_tab	(self)
_create_traces_tab	(self)
_populate_traces	(self)
_curve_row	(self, item, index)	Args:
_scatter_row	(self, item, index)	Args:
_bar_row	(self, name, items, index)	One row in the Traces tab for a group of BarGraphItems that
_choose_color	(self, color_type)	Args:
_load_persistent	(self)
_save_persistent	(self)
_apply_settings	(self)
_reset_defaults	(self)
_accept_and_apply	(self)
closeEvent	(self, event)	Args:

CustomPlotItem (extends pg.PlotItem)

Method	Signature	Description
__init__	(self, *args, **kwargs)	Args:
getContextMenus	(self, event)	Args:

ExclusionRegion (extends pg.LinearRegionItem)

A vertical shaded band marking an excluded X-range.

Each region carries a scope: - 'element' : applies only to the element currently displayed. Drawn with a red dashed outline. - 'sample' : applies to every element in the active sample. Drawn with a thicker blue solid outline so it is visually distinct from element-scope bands.

Drag the middle to move, drag the edges to resize. Right-click on the band for a small menu (Remove / Edit bounds / Change scope / Clear all). The widget that owns this region is held as _owner so the region can ask the owner to apply the chosen action.

Method	Signature	Description
__init__	(self, values, owner, scope = 'element')	Args:
scope	(self)	Returns:
set_scope	(self, scope)	Change scope in-place (updates the visual styling).
mouseClickEvent	(self, ev)	Args:
_show_context_menu	(self, ev)	Args:
_edit_bounds_dialog	(self)

EnhancedPlotWidget (extends pg.PlotWidget)

Method	Signature	Description
__init__	(self, parent = None)	Args:
setup_appearance	(self)
setup_interaction_features	(self)
_install_autorange_button	(self)	Overlay a small auto-scale button in the top-right corner.
_reposition_autorange_btn	(self)
resizeEvent	(self, event)	Args:
_install_exclusion_context_menu	(self)	Add 'Add exclusion region here (this element / whole sample)' and
_capture_context_menu_position	(self)	Cache the data-X under the cursor when the context menu opens.
_add_exclusion_region_at_cursor	(self, scope = 'element')	Create a new band centred on the last right-click X-position.
add_exclusion_region	(self, x_min, x_max, scope = 'element')	Add a new exclusion band spanning [x_min, x_max] (data coords).
remove_exclusion_region	(self, region)	Remove a single exclusion band. Emits exclusionRegionsChanged.
clear_exclusion_regions	(self)	Remove every exclusion band. Emits exclusionRegionsChanged.
get_exclusion_regions	(self)	Return excluded X-ranges as a list of (x_min, x_max, scope).
set_exclusion_regions	(self, regions)	Replace the current set of exclusion bands with the given list.
get_exclusion_mask	(self, x_array)	Boolean mask the same length as x_array.
_on_region_edited	(self, *_)	Args:
_emit_exclusion_changed	(self)
clear	(self)
open_plot_settings	(self)
mouseDoubleClickEvent	(self, event)	Hit-detection priority:
_find_closest_scatter	(self, scene_pos, threshold_px = 20)	Args:
_find_closest_curve	(self, scene_pos, threshold_px = 15)	Args:
wheelEvent	(self, event)	Args:
update_plot	(self, time_array, data)	Args:
mouse_moved	(self, pos)	Args:
clear_plot	(self)

BasicPlotWidget (extends pg.PlotWidget)

Method	Signature	Description
__init__	(self, parent = None)	Args:
setup_basic_appearance	(self)
_install_autorange_button	(self)
_reposition_autorange_btn	(self)
resizeEvent	(self, event)	Args:
update_plot	(self, time_array, data)	Args:
clear_plot	(self)
setTitle	(self, title)	Args:

CalibrationPlotWidget (extends EnhancedPlotWidget)

Calibration plot with interactive exclusion of outlier points.

Method	Signature	Description
__init__	(self, parent = None)	Args:
setup_interaction_features	(self)	Override: calibration plot uses no crosshair lines.
_setup_calibration_appearance	(self)
_build_calibration_items	(self)
setLabel	(self, axis, text, units = None, color = None, font = None)	Args:
setTitle	(self, title)	Args:
update_plot	(self, x_data, y_data, y_std, method = 'zero', y_fit = None, key = 'Da	Refresh the plot with new data.
clear_plot	(self)
mouseDoubleClickEvent	(self, event)	Args:
_redraw_markers	(self)
_redraw_fit_line	(self)
_redraw_equation	(self)
_reposition_equation	(self)
_on_scatter_clicked	(self, _plot, points, event = None)	A single press on a scatter fires this. We queue the
_emit_pending_click	(self)

BarEditorDialog (extends QDialog)

Simple editor for a single m/z bar: fill color.

Operates directly on the bar meta-dict so changes are immediately reflected in the chart and survive subsequent data refreshes.

Method	Signature	Description
__init__	(self, meta, parent = None)	Args:
_setup_ui	(self)
_pick_fill	(self)
_apply	(self)

MzBarPlotWidget (extends pg.PlotWidget)

Drop-in pg.PlotWidget for the inline m/z bar chart.

Gives the same double-click-to-edit experience as EnhancedPlotWidget:

Double-click title → TitleEditorDialog Double-click left axis → AxisLabelEditorDialog('left') Double-click bottom axis → AxisLabelEditorDialog('bottom') Double-click a bar → BarEditorDialog (fill color) Double-click empty area → BackgroundEditorDialog Right-click anywhere → 'Plot Settings…' → PlotSettingsDialog (Font + Grid tabs; Traces tab omitted because bars are not PlotDataItem objects)

Method	Signature	Description
__init__	(self, parent = None)	Args:
open_plot_settings	(self)
set_bar_meta	(self, meta)	Store per-bar metadata dicts for hit-testing on double-click.
mouseDoubleClickEvent	(self, event)	Hit-detection priority (same order as EnhancedPlotWidget):

Functions

_editor_dialog_qss

def _editor_dialog_qss()

Stylesheet applied to every small plot editor dialog (TraceEditor, ScatterEditor, AxisLabelEditor, TitleEditor, LegendEditor, BackgroundEditor, etc). Pulls from the current theme.

Returns:

• object: Result of the operation.

_editor_header_qss

def _editor_header_qss()

Header label at the top of each editor dialog (was '#2c3e50' bold).

Returns:

• object: Result of the operation.

_editor_ok_button_qss

def _editor_ok_button_qss()

Primary OK/Apply button. Was hardcoded #3498db → #2980b9.

Returns:

• object: Result of the operation.

_editor_cancel_button_qss

def _editor_cancel_button_qss()

Neutral Cancel button. Was hardcoded #95a5a6 → #7f8c8d.

Returns:

• object: Result of the operation.

_color_swatch_qss

def _color_swatch_qss(hex_color)

Small color picker swatch. hex_color may be any valid CSS color.

Args:

• hex_color (Any): The hex color.

Returns:

• object: Result of the operation.

_tall_color_swatch_qss

def _tall_color_swatch_qss(hex_color)

Full-width color swatch used in the PlotSettingsDialog form rows (font color / background color / grid color). Keeps the border theme-aware so the button doesn't look pasted-on in dark mode.

Args:

• hex_color (Any): The hex color.

Returns:

• object: Result of the operation.

_hint_label_qss

def _hint_label_qss()

Italic tip / hint labels (the 'Double-click any element…' line and the 'Edit all traces…' header on the Traces tab). Used to be hardcoded

555/#666/#999 which is unreadable in dark mode.

Returns:

• object: Result of the operation.

_trace_row_qss

def _trace_row_qss()

Per-trace row background on the Traces tab (formerly hardcoded white #fff). Uses the theme's tertiary surface in both light and dark mode, with a left-edge accent bar to visually distinguish it from scatter rows.

Returns:

• object: Result of the operation.

_scatter_row_qss

def _scatter_row_qss()

Per-scatter row background on the Traces tab (formerly cream #fff8f0 with an orange accent). Shares the same dark surface as trace rows but uses a 'success' / teal left-edge accent so scatter vs. line is still visually distinguishable — no more olive-yellow warning color showing up in dark mode.

Returns:

• object: Result of the operation.

_inline_apply_btn_qss

def _inline_apply_btn_qss(variant = 'primary')

Small 'Apply' button rendered inside each trace/scatter row. variant is either 'primary' (trace rows) or 'warn' (scatter rows). Theme-aware replacement for the old hardcoded blue/orange — the 'warn' variant now uses the theme's success color to stay readable.

Args:

• variant (Any): The variant.

Returns:

• object: Result of the operation.

_install_theme_subscription

def _install_theme_subscription(dialog)

Attach the editor_dialog_qss to a dialog AND keep it updated when the user toggles theme. Safe to call from any editor dialog's init.

Args:

• dialog (Any): Parent or target dialog.

get_system_font_families

def get_system_font_families()

Get available system font families from Qt font database, sorted with common scientific fonts first.

Returns:

• list: Sorted list of font family names