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An implementation for a generic input dialog in PyQt5. String and/or numeric values can be obtained with just one line of code. See the "Testing" section at the end of the file.
"""
Generic input dialog in PyQt5.
By Francesco Santini <francesco.santini@gmail.com>
Code released in the Public Domain (CC-0)
"""
from __future__ import annotations
from typing import Any, Union
from collections import OrderedDict
from PyQt5.QtWidgets import QDialog, QWidget, QSpinBox, QDoubleSpinBox, QLineEdit, QFormLayout, QVBoxLayout, \
QHBoxLayout, QGroupBox, QDialogButtonBox, QLabel, QApplication, QSlider, QCheckBox, QComboBox
from PyQt5.QtCore import Qt
import abc
import sys
class MixedDict(OrderedDict):
"""
A class that behaves as a list and as a dictionary.
If the key is integer, returns the item at that position, otherwise behave as a dictionary
"""
def __init__(self, *args, **kwargs):
OrderedDict.__init__(self, *args, **kwargs)
def key_at(self, pos):
return list(self.keys())[pos]
def __getitem__(self, key):
if type(key) == int:
return OrderedDict.__getitem__(self, self.key_at(key))
else:
return OrderedDict.__getitem__(self, key)
def __setitem__(self, key, value):
if type(key) == int:
dict_key = self.key_at(key) # if this fails, it will raise a keyerror, and we are fine with that
else:
dict_key = key
OrderedDict.__setitem__(self, dict_key, value)
def __iter__(self):
return iter(self.values())
class InputClass(abc.ABC):
"""
Abstract implementation of an input class
"""
@abc.abstractmethod
def get_widget(self) -> QWidget:
pass
@abc.abstractmethod
def get_label(self) -> str:
pass
@abc.abstractmethod
def get_value(self) -> Any:
pass
## Default input classes
class TextLineInput(InputClass):
def __init__(self, label:str, initial_value:str =''):
self.label = label
self.line_edit = QLineEdit()
self.line_edit.setText(initial_value)
def get_widget(self) -> QWidget:
return self.line_edit
def get_label(self) -> str:
return self.label
def get_value(self) -> Any:
return self.line_edit.text()
class IntSpinInput(InputClass):
def __init__(self, label:str, initial_value:int=0, min:int=0, max:int=99, increment:int=1):
self.label = label
self.widget = QSpinBox()
self.widget.setMinimum(min)
self.widget.setMaximum(max)
self.widget.setValue(initial_value)
self.widget.setSingleStep(increment)
def get_label(self) -> str:
return self.label
def get_widget(self) -> QWidget:
return self.widget
def get_value(self) -> Any:
return self.widget.value()
class FloatSpinInput(InputClass):
def __init__(self, label:str, initial_value:float=0.0, min:float=0.0, max:float=99.0, increment:float=1.0):
self.label = label
self.widget = QDoubleSpinBox()
self.widget.setMinimum(min)
self.widget.setMaximum(max)
self.widget.setValue(initial_value)
self.widget.setSingleStep(increment)
def get_label(self) -> str:
return self.label
def get_widget(self) -> QWidget:
return self.widget
def get_value(self) -> Any:
return self.widget.value()
class IntSliderInput(InputClass):
def __init__(self, label:str, initial_value:int=0, min:int=0, max:int=99, increment:int=1):
self.label = label
self.widget = QWidget()
self.slider = QSlider(self.widget)
self.slider.setOrientation(Qt.Horizontal)
self.slider.setMinimum(min)
self.slider.setMaximum(max)
self.slider.setValue(initial_value)
self.slider.setSingleStep(increment)
self.slider_label = QLabel(self.widget)
self.slider_label.setText(str(initial_value))
layout = QHBoxLayout(self.widget)
layout.addWidget(self.slider)
layout.addWidget(self.slider_label)
self.slider.valueChanged.connect(lambda value: self.slider_label.setText(str(value)))
def get_label(self) -> str:
return self.label
def get_widget(self) -> QWidget:
return self.widget
def get_value(self) -> Any:
return self.slider.value()
class BooleanInput(InputClass):
def __init__(self, label: str, default:bool = False):
self.label = label
self.widget = QCheckBox()
self.widget.setChecked(default)
def get_label(self) -> str:
return self.label
def get_widget(self) -> QWidget:
return self.widget
def get_value(self) -> Any:
return self.widget.isChecked()
class OptionInput(InputClass):
def __init__(self, label:str, value_list:list[Union[str, tuple[str, Any]]], default=None):
self.label = label
self.widget = QComboBox()
self.output_list = []
default_set = False
for index, v in enumerate(value_list):
if type(v) == str:
self.widget.addItem(v)
self.output_list.append(v)
if default is not None:
if default == v:
default_set = True
self.widget.setCurrentIndex(index)
else: # it is a tuple, specified by the type hint in the constructor
self.widget.addItem(v[0])
self.output_list.append(v[1])
if default is not None:
if default in v:
default_set = True
self.widget.setCurrentIndex(index)
if not default_set and type(default) == int:
self.widget.setCurrentIndex(default)
def get_label(self) -> str:
return self.label
def get_widget(self) -> QWidget:
return self.widget
def get_value(self) -> Any:
return self.output_list[self.widget.currentIndex()]
## Dialog class implementation
class GenericDialog(QDialog):
def __init__(self, title: str, input_list: list[InputClass], parent=None):
QDialog.__init__(self, parent)
self.setWindowTitle(title)
self.verticalLayout = QVBoxLayout(self)
self.groupBox = QGroupBox(title, self)
self.formLayout = QFormLayout(self.groupBox)
self.buttonBox = QDialogButtonBox(self)
self.buttonBox.setOrientation(Qt.Horizontal)
self.buttonBox.setStandardButtons(QDialogButtonBox.Cancel | QDialogButtonBox.Ok)
self.buttonBox.accepted.connect(lambda: self.exit_dialog(True))
self.buttonBox.rejected.connect(lambda: self.exit_dialog(False))
self.input_list = input_list
for position, input_obj in enumerate(input_list):
label = QLabel(self.groupBox)
label.setText(input_obj.get_label())
self.formLayout.setWidget(position, QFormLayout.LabelRole, label)
input_field = input_obj.get_widget()
self.formLayout.setWidget(position, QFormLayout.FieldRole, input_field)
self.verticalLayout.addWidget(self.groupBox)
self.verticalLayout.addWidget(self.buttonBox)
self.resize(self.verticalLayout.sizeHint())
self.output = None
self.accepted = False
self.setModal(True)
def exit_dialog(self, accepted):
self.accepted = accepted
self.close()
def closeEvent(self, event):
self.output = MixedDict()
for input_obj in self.input_list:
self.output[input_obj.get_label()] = input_obj.get_value()
## This is the main function that should be called
def show_dialog(title: str, input_list: list[InputClass], parent=None) -> (bool, MixedDict):
dialog = GenericDialog(title, input_list, parent)
dialog.exec()
# this will stop until the dialog is closed
if dialog.accepted is None:
return None
return dialog.accepted, dialog.output
## Testing
if __name__ == '__main__':
app = QApplication(sys.argv)
app.setQuitOnLastWindowClosed(True)
accepted, values = show_dialog("Test", [TextLineInput('Text input'),
IntSpinInput('My Int', 10, -100, 100),
FloatSpinInput('My Float'),
IntSliderInput('My slider'),
BooleanInput('Bool value'),
OptionInput('My string options', [
'option 1',
'option 2',
'option 3'
], 'option 3'),
OptionInput('My int options', [
('option 1', 1.1),
('option 2', 2.2),
('option 3', 3.3)
], 2.2)
])
# Note: for option inputs, the value list can be a list of strings, and then the output is the string itself, or a
# list of tuples, where the first element is a string (the label) and the second is the returned value (any).
# The default value for options can be the label string, the default returned value, or an integer index
# returned values can be accessed by key or by position
print(values['My Int'])
print(values[2])
# they can be iterated like a list
for v in values:
print(v)
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