Source code for mantidimaging.gui.utility.qt_helpers

# Copyright (C) 2024 ISIS Rutherford Appleton Laboratory UKRI
# SPDX - License - Identifier: GPL-3.0-or-later
Module containing helper functions relating to PyQt.
from __future__ import annotations

import os
from enum import IntEnum, auto
from logging import getLogger
from typing import Any
from import Callable

from PyQt5 import uic  # type: ignore
from PyQt5.QtCore import QObject, Qt
from PyQt5.QtWidgets import (QLabel, QLineEdit, QSpinBox, QDoubleSpinBox, QCheckBox, QWidget, QSizePolicy, QAction,
                             QMenu, QPushButton, QLayout, QFileDialog, QComboBox)

from mantidimaging.core.utility import finder

MAX_SPIN_BOX = 2147483647
INPUT_DIALOG_FLAGS = Qt.WindowSystemMenuHint | Qt.WindowTitleHint | Qt.WindowCloseButtonHint

[docs] class BlockQtSignals: """ Used to block Qt signals from a selection of QWidgets within a context. """ def __init__(self, q_objects: QObject | list[QObject]): if not isinstance(q_objects, list): q_objects = [q_objects] for obj in q_objects: assert isinstance(obj, QObject), \ "This class must be used with QObjects" self.q_objects = q_objects self.previous_values = None def __enter__(self): self.previous_values = \ [obj.blockSignals(True) for obj in self.q_objects] def __exit__(self, *args): for obj, prev in zip(self.q_objects, self.previous_values, strict=True): obj.blockSignals(prev)
[docs] def compile_ui(ui_file, qt_obj=None): base_path = finder.ROOT_PATH return uic.loadUi(os.path.join(base_path, ui_file), qt_obj)
[docs] def select_directory(field, caption): assert isinstance(field, QLineEdit), (f"The passed object is of type {type(field)}. This function only works with " "QLineEdit") # open file dialog and set the text if file is selected field.setText(QFileDialog.getExistingDirectory(caption=caption))
[docs] def get_value_from_qwidget(widget: QWidget): if isinstance(widget, QLineEdit): return widget.text() elif isinstance(widget, QSpinBox) or isinstance(widget, QDoubleSpinBox): return widget.value() elif isinstance(widget, QCheckBox): return widget.isChecked()
[docs] class Type(IntEnum): STR = auto() TUPLE = auto() NONETYPE = auto() LIST = auto() FLOAT = auto() INT = auto() CHOICE = auto() BOOL = auto() LABEL = auto() STACK = auto() BUTTON = auto()
[docs] def on_change_and_disable(widget: QWidget, on_change: Callable): """ Makes sure the widget is disabled while running the on_update method. This is required for spin boxes that continue increasing when generating a preview image is computationally intensive. :param widget: The widget to disable. :param on_change: The method to call when the widget has been changed. """ widget.setEnabled(False) on_change() widget.setEnabled(True)
[docs] def add_property_to_form(label: str, dtype: Type | str, default_value=None, valid_values=None, tooltip=None, on_change=None, form=None, filters_view=None, run_on_press=None, single_step_size=None) -> tuple[QLabel | QLineEdit, Any]: """ Adds a property to the algorithm dialog. Handles adding basic data options to the UI. :param label: Label that describes the option :param dtype: Option data type (any of: file, int, float, bool, list) :param default_value: Optionally select the default value :param valid_values: Optionally provide the range or selection of valid values :param tooltip: Optional tooltip text to show on property :param on_change: Function to be called when the property changes :param form: Form layout to optionally add the new widgets to :param filters_view: The Filter window view - passed to connect Type.STACK to the stack change events :param run_on_press: Run this function on press, specialisation for button. :param single_step_size: Optionally provide a step size for a SpinBox widget. """ # By default assume the left hand side widget will be a label left_widget = QLabel(label) right_widget = None # sanitize default value if isinstance(default_value, str) and default_value.lower() == "none": default_value = None def set_spin_box(box, cast_func): """ Helper function to set default options on a spin box. """ if valid_values: box.setMinimum(valid_values[0]) box.setMaximum(valid_values[1]) else: box.setMinimum(0) box.setMaximum(10000) if default_value: box.setValue(cast_func(default_value)) if single_step_size is not None: box.setSingleStep(single_step_size) elif cast_func == float: # Override the default step size for QDoubleSpinBox box.setSingleStep(0.1) if dtype in ['str', Type.STR, 'tuple', Type.TUPLE, 'NoneType', Type.NONETYPE, 'list', Type.LIST]: # TODO for tuple with numbers add N combo boxes, N = number of tuple members right_widget = QLineEdit() right_widget.setToolTip(tooltip) right_widget.setText(default_value) if on_change is not None: right_widget.editingFinished.connect(lambda: on_change()) elif dtype == 'int' or dtype == Type.INT: right_widget = QSpinBox() right_widget.setKeyboardTracking(False) set_spin_box(right_widget, int) if on_change is not None: right_widget.valueChanged.connect(lambda: on_change_and_disable(right_widget, on_change)) elif dtype == 'float' or dtype == Type.FLOAT: right_widget = QDoubleSpinBox() set_spin_box(right_widget, float) right_widget.setKeyboardTracking(False) if on_change is not None: right_widget.valueChanged.connect(lambda: on_change_and_disable(right_widget, on_change)) elif dtype == 'bool' or dtype == Type.BOOL: right_widget = QCheckBox() if isinstance(default_value, bool): right_widget.setChecked(default_value) elif isinstance(default_value, str): right_widget.setChecked("True" == default_value) elif default_value is None: # have to pick something right_widget.setChecked(False) else: raise ValueError(f"Cannot convert value {default_value} to a Boolean.") if on_change is not None: right_widget.stateChanged[int].connect(lambda: on_change()) elif dtype == "choice" or dtype == Type.CHOICE: right_widget = QComboBox() right_widget.setSizeAdjustPolicy(QComboBox.SizeAdjustPolicy.AdjustToContents) if valid_values: right_widget.addItems(valid_values) if on_change is not None: right_widget.currentIndexChanged[int].connect(lambda: on_change()) elif dtype == 'stack' or dtype == Type.STACK: from mantidimaging.gui.widgets.dataset_selector import DatasetSelectorWidgetView right_widget = DatasetSelectorWidgetView(filters_view, show_stacks=True) if on_change is not None: right_widget.currentIndexChanged[int].connect(lambda: on_change()) elif dtype == 'button' or dtype == Type.BUTTON: left_widget = QPushButton(label) if run_on_press is not None: left_widget.clicked.connect(lambda: run_on_press()) elif dtype == 'label' or dtype == Type.LABEL: # do nothing for label, just use the left widget pass else: raise ValueError("Unknown data type") if tooltip: if left_widget: left_widget.setToolTip(tooltip) if right_widget: right_widget.setToolTip(tooltip) # right widget check avoids printing debug msg for labels only if tooltip is None and right_widget is not None: log = getLogger(__name__) log.debug("Missing tooltip for %s", label) if left_widget: left_widget.setSizePolicy(QSizePolicy.Policy.Maximum, QSizePolicy.Policy.Fixed) if right_widget: right_widget.setSizePolicy(QSizePolicy.Policy.Maximum, QSizePolicy.Policy.Fixed) # Add to form layout if form is not None: form.addRow(left_widget, right_widget) return left_widget, right_widget
[docs] def delete_all_widgets_from_layout(lo): """ Removes and deletes all child widgets form a layout. :param lo: Layout to clean """ # For each item in the layout (removed as iterated) while lo.count() > 0: item = lo.takeAt(0) # Recurse for child layouts if isinstance(item, QLayout): delete_all_widgets_from_layout(item) # Orphan child widgets (seting a None parent removes them from the # layout and marks them for deletion) elif item.widget() is not None: item.widget().setParent(None)
[docs] def populate_menu(menu: QMenu, actions_list: list[QAction]): for (menu_text, func) in actions_list: if func is None: menu.addSeparator() else: action = QAction(menu_text, menu) action.triggered.connect(func) menu.addAction(action)