Appendix: Useful Development Info

General

• Disable widget:

widget.setEnabled(False)

Layout

• Insert widget:

layout.insertWidget(pos, widget)

QPushButton

• How to connect to the clicked event:

  button.clicked.connect(callback)
  

• How to change the button label:

  button.setText('New text')
  

QTextLabel

• How to change the label text:

  label.setText('New text')
  

QLineEdit

• How to get lineEdit text:

  lineEdit.text()
  

• How to change the lineEdit text:

  lineEdit.setText('New text')
  

• How to add a validator for an input (with a regular expression)

  rx = QRegExp("^([a-zA-Z][]a-zA-Z0-9_]*)$")
  lineedit.setValidator(QRegExpValidator(rx))
  

• How to change the placeholder text:

  lineEdit.setPlaceholderText('New text')
  

QComboBox

• How to clear elements:

  combobox.clear()
  

• How to add items:

  items = ['item1', 'item2', 'item3']
  combobox.addItems(items)
  

• How to get the current selection:

  combobox.currentText()
  

• How to get the index for an item:

  combobox.findText('item')
  

• How to change current selected item:

  combobox.setCurrentIndex(index)
  

• How to connect to the 'selection changed' event:

  combobox.currentIndexChanged.connect(callback)
  

• How to make it not editable:

  combobox.setEditable(False)
  

QCheckBox

• How to get checkbox status:

  checkbox.isChecked()
  

• How to change checkbox status:

  checkbox.setChecked(state)
  

• How to connect to the 'value changed' event:

  checkbox.stateChanged.connect(callback)
  

QSpinBox

• How to get the current value:

  spinBox.value()
  

• How to set the current value:

  spinBox.setValue(0)
  

• How to set the maximum and minimum range allowed:

# Maximum
spinBox.setMaximum(max_limit)

# Minimum
spinbox.setMinimum(min_limit)


# System maximum float value:
import sys
float_max = sys.float_info.max

• How to connect to the 'value changed' event:

  spinbox.valueChanged.connect(callback)