QFormLayout

The QFormLayout class manages forms of input widgets and their associated labels. More

Inheritance diagram of PySide2.QtWidgets.QFormLayout

Synopsis

Functions

Detailed Description

QFormLayout is a convenience layout class that lays out its children in a two-column form. The left column consists of labels and the right column consists of “field” widgets (line editors, spin boxes, etc.).

Traditionally, such two-column form layouts were achieved using QGridLayout . QFormLayout is a higher-level alternative that provides the following advantages:

  • Adherence to the different platform’s look and feel guidelines.

    For example, the macOS Aqua and KDE guidelines specify that the labels should be right-aligned, whereas Windows and GNOME applications normally use left-alignment.

  • Support for wrapping long rows.

    For devices with small displays, QFormLayout can be set to wrap long rows , or even to wrap all rows .

  • Convenient API for creating label–field pairs.

    The addRow() overload that takes a QString and a QWidget * creates a QLabel behind the scenes and automatically set up its buddy. We can then write code like this:

    formLayout = QFormLayout()
    formLayout.addRow(self.tr("&Name:"), nameLineEdit)
    formLayout.addRow(self.tr("&Email:"), emailLineEdit)
    formLayout.addRow(self.tr("&Age:"), ageSpinBox)
    setLayout(formLayout)
    

    Compare this with the following code, written using QGridLayout :

    nameLabel = QLabel(self.tr("&Name:"))
    nameLabel.setBuddy(nameLineEdit)
    
    emailLabel = QLabel(self.tr("&Name:"))
    emailLabel.setBuddy(emailLineEdit)
    
    ageLabel = QLabel(self.tr("&Name:"))
    ageLabel.setBuddy(ageSpinBox)
    
    gridLayout = QGridLayout()
    gridLayout.addWidget(nameLabel, 0, 0)
    gridLayout.addWidget(nameLineEdit, 0, 1)
    gridLayout.addWidget(emailLabel, 1, 0)
    gridLayout.addWidget(emailLineEdit, 1, 1)
    gridLayout.addWidget(ageLabel, 2, 0)
    gridLayout.addWidget(ageSpinBox, 2, 1)
    setLayout(gridLayout)
    

The table below shows the default appearance in different styles.

QCommonStyle derived styles (except QPlastiqueStyle)

QMacStyle

QPlastiqueStyle

Qt Extended styles

qformlayout-win1

qformlayout-mac2

qformlayout-kde3

qformlayout-qpe4

Traditional style used for Windows, GNOME, and earlier versions of KDE. Labels are left aligned, and expanding fields grow to fill the available space. (This normally corresponds to what we would get using a two-column QGridLayout .)

Style based on the macOS Aqua guidelines. Labels are right-aligned, the fields don’t grow beyond their size hint, and the form is horizontally centered.

Recommended style for KDE applications. Similar to MacStyle, except that the form is left-aligned and all fields grow to fill the available space.

Default style for Qt Extended styles. Labels are right-aligned, expanding fields grow to fill the available space, and row wrapping is enabled for long lines.

The form styles can be also be overridden individually by calling setLabelAlignment() , setFormAlignment() , setFieldGrowthPolicy() , and setRowWrapPolicy() . For example, to simulate the form layout appearance of QMacStyle on all platforms, but with left-aligned labels, you could write:

formLayout.trowWrapPolicy(QFormLayout.DontWrapRows)
formLayout.setFieldGrowthPolicy(QFormLayout.FieldsStayAtSizeHint)
formLayout.setFormAlignment(Qt.AlignHCenter | Qt.AlignTop)
formLayout.setLabelAlignment(Qt.AlignLeft)
class PySide2.QtWidgets.QFormLayout([parent=None])

Constructs a new form layout with the given parent widget.

See also

setLayout()

PySide2.QtWidgets.QFormLayout.FieldGrowthPolicy

This enum specifies the different policies that can be used to control the way in which the form’s fields grow.

Constant

Description

QFormLayout.FieldsStayAtSizeHint

The fields never grow beyond their effective size hint . This is the default for QMacStyle.

QFormLayout.ExpandingFieldsGrow

Fields with an horizontal size policy of Expanding or MinimumExpanding will grow to fill the available space. The other fields will not grow beyond their effective size hint. This is the default policy for Plastique.

QFormLayout.AllNonFixedFieldsGrow

All fields with a size policy that allows them to grow will grow to fill the available space. This is the default policy for most styles.

PySide2.QtWidgets.QFormLayout.RowWrapPolicy

This enum specifies the different policies that can be used to control the way in which the form’s rows wrap.

Constant

Description

QFormLayout.DontWrapRows

Fields are always laid out next to their label. This is the default policy for all styles except Qt Extended styles.

QFormLayout.WrapLongRows

Labels are given enough horizontal space to fit the widest label, and the rest of the space is given to the fields. If the minimum size of a field pair is wider than the available space, the field is wrapped to the next line. This is the default policy for Qt Extended styles.

QFormLayout.WrapAllRows

Fields are always laid out below their label.

See also

rowWrapPolicy

PySide2.QtWidgets.QFormLayout.ItemRole

This enum specifies the types of widgets (or other layout items) that may appear in a row.

Constant

Description

QFormLayout.LabelRole

A label widget.

QFormLayout.FieldRole

A field widget.

QFormLayout.SpanningRole

A widget that spans label and field columns.

PySide2.QtWidgets.QFormLayout.addRow(layout)
Parameters

layoutPySide2.QtWidgets.QLayout

This is an overloaded function.

Adds the specified layout at the end of this form layout. The layout spans both columns.

PySide2.QtWidgets.QFormLayout.addRow(label, field)
Parameters

This is an overloaded function.

PySide2.QtWidgets.QFormLayout.addRow(label, field)
Parameters

Adds a new row to the bottom of this form layout, with the given label and field .

See also

insertRow()

PySide2.QtWidgets.QFormLayout.addRow(widget)
Parameters

widgetPySide2.QtWidgets.QWidget

This is an overloaded function.

Adds the specified widget at the end of this form layout. The widget spans both columns.

PySide2.QtWidgets.QFormLayout.addRow(labelText, field)
Parameters
PySide2.QtWidgets.QFormLayout.addRow(labelText, field)
Parameters
PySide2.QtWidgets.QFormLayout.fieldGrowthPolicy()
Return type

FieldGrowthPolicy

This property holds the way in which the form’s fields grow.

The default value depends on the widget or application style. For QMacStyle, the default is FieldsStayAtSizeHint ; for QCommonStyle derived styles (like Plastique and Windows), the default is ExpandingFieldsGrow ; for Qt Extended styles, the default is AllNonFixedFieldsGrow .

If none of the fields can grow and the form is resized, extra space is distributed according to the current form alignment .

PySide2.QtWidgets.QFormLayout.formAlignment()
Return type

Alignment

This property holds the alignment of the form layout’s contents within the layout’s geometry.

The default value depends on the widget or application style. For QMacStyle, the default is AlignHCenter | AlignTop ; for the other styles, the default is AlignLeft | AlignTop .

PySide2.QtWidgets.QFormLayout.getItemPosition(index)
Parameters

index – int

Retrieves the row and role (column) of the item at the specified index . If index is out of bounds, *``rowPtr`` is set to -1; otherwise the row is stored in *``rowPtr`` and the role is stored in *``rolePtr`` .

PySide2.QtWidgets.QFormLayout.getLayoutPosition(layout)
Parameters

layoutPySide2.QtWidgets.QLayout

Retrieves the row and role (column) of the specified child layout . If layout is not in the form layout, *``rowPtr`` is set to -1; otherwise the row is stored in *``rowPtr`` and the role is stored in *``rolePtr`` .

PySide2.QtWidgets.QFormLayout.getWidgetPosition(widget)
Parameters

widgetPySide2.QtWidgets.QWidget

Retrieves the row and role (column) of the specified widget in the layout. If widget is not in the layout, *``rowPtr`` is set to -1; otherwise the row is stored in *``rowPtr`` and the role is stored in *``rolePtr`` .

PySide2.QtWidgets.QFormLayout.horizontalSpacing()
Return type

int

This property holds the spacing between widgets that are laid out side by side.

By default, if no value is explicitly set, the layout’s horizontal spacing is inherited from the parent layout, or from the style settings for the parent widget.

See also

verticalSpacing pixelMetric() PM_LayoutHorizontalSpacing

PySide2.QtWidgets.QFormLayout.insertRow(row, label, field)
Parameters

Inserts a new row at position row in this form layout, with the given label and field . If row is out of bounds, the new row is added at the end.

See also

addRow()

PySide2.QtWidgets.QFormLayout.insertRow(row, labelText, field)
Parameters
PySide2.QtWidgets.QFormLayout.insertRow(row, labelText, field)
Parameters
PySide2.QtWidgets.QFormLayout.insertRow(row, widget)
Parameters

This is an overloaded function.

Inserts the specified widget at position row in this form layout. The widget spans both columns. If row is out of bounds, the widget is added at the end.

PySide2.QtWidgets.QFormLayout.insertRow(row, label, field)
Parameters

This is an overloaded function.

PySide2.QtWidgets.QFormLayout.insertRow(row, layout)
Parameters

This is an overloaded function.

Inserts the specified layout at position row in this form layout. The layout spans both columns. If row is out of bounds, the widget is added at the end.

PySide2.QtWidgets.QFormLayout.itemAt(row, role)
Parameters
Return type

PySide2.QtWidgets.QLayoutItem

Returns the layout item in the given row with the specified role (column). Returns None if there is no such item.

See also

itemAt() setItem()

PySide2.QtWidgets.QFormLayout.labelAlignment()
Return type

Alignment

This property holds the horizontal alignment of the labels.

The default value depends on the widget or application style. For QCommonStyle derived styles, except for QPlastiqueStyle, the default is AlignLeft ; for the other styles, the default is AlignRight .

See also

formAlignment

PySide2.QtWidgets.QFormLayout.labelForField(field)
Parameters

fieldPySide2.QtWidgets.QLayout

Return type

PySide2.QtWidgets.QWidget

This is an overloaded function.

PySide2.QtWidgets.QFormLayout.labelForField(field)
Parameters

fieldPySide2.QtWidgets.QWidget

Return type

PySide2.QtWidgets.QWidget

Returns the label associated with the given field .

See also

itemAt()

PySide2.QtWidgets.QFormLayout.removeRow(layout)
Parameters

layoutPySide2.QtWidgets.QLayout

This is an overloaded function.

Deletes the row corresponding to layout from this form layout.

After this call, rowCount() is decremented by one. All widgets and nested layouts that occupied this row are deleted. That includes both the field widget(s) and the label, if any. All following rows are shifted up one row and the freed vertical space is redistributed amongst the remaining rows.

You can use this function to undo a previous addRow() or insertRow() :

QFormLayout *flay = ...;
QPointer<QVBoxLayout> vbl = new QVBoxLayout;
flay->insertRow(2, "User:", vbl);
// later:
flay->removeRow(layout); // vbl == nullptr at this point

If you want to remove the row from the form layout without deleting the inserted layout, use takeRow() instead.

See also

takeRow()

PySide2.QtWidgets.QFormLayout.removeRow(widget)
Parameters

widgetPySide2.QtWidgets.QWidget

This is an overloaded function.

Deletes the row corresponding to widget from this form layout.

After this call, rowCount() is decremented by one. All widgets and nested layouts that occupied this row are deleted. That includes both the field widget(s) and the label, if any. All following rows are shifted up one row and the freed vertical space is redistributed amongst the remaining rows.

You can use this function to undo a previous addRow() or insertRow() :

QFormLayout *flay = ...;
QPointer<QLineEdit> le = new QLineEdit;
flay->insertRow(2, "User:", le);
// later:
flay->removeRow(le); // le == nullptr at this point

If you want to remove the row from the layout without deleting the widgets, use takeRow() instead.

See also

takeRow()

PySide2.QtWidgets.QFormLayout.removeRow(row)
Parameters

row – int

Deletes row row from this form layout.

row must be non-negative and less than rowCount() .

After this call, rowCount() is decremented by one. All widgets and nested layouts that occupied this row are deleted. That includes both the field widget(s) and the label, if any. All following rows are shifted up one row and the freed vertical space is redistributed amongst the remaining rows.

You can use this function to undo a previous addRow() or insertRow() :

QFormLayout *flay = ...;
QPointer<QLineEdit> le = new QLineEdit;
flay->insertRow(2, "User:", le);
// later:
flay->removeRow(2); // le == nullptr at this point

If you want to remove the row from the layout without deleting the widgets, use takeRow() instead.

See also

takeRow()

PySide2.QtWidgets.QFormLayout.rowCount()
Return type

int

Returns the number of rows in the form.

See also

count()

PySide2.QtWidgets.QFormLayout.rowWrapPolicy()
Return type

RowWrapPolicy

This property holds the way in which the form’s rows wrap.

The default value depends on the widget or application style. For Qt Extended styles, the default is WrapLongRows ; for the other styles, the default is DontWrapRows .

If you want to display each label above its associated field (instead of next to it), set this property to WrapAllRows .

PySide2.QtWidgets.QFormLayout.setFieldGrowthPolicy(policy)
Parameters

policyFieldGrowthPolicy

This property holds the way in which the form’s fields grow.

The default value depends on the widget or application style. For QMacStyle, the default is FieldsStayAtSizeHint ; for QCommonStyle derived styles (like Plastique and Windows), the default is ExpandingFieldsGrow ; for Qt Extended styles, the default is AllNonFixedFieldsGrow .

If none of the fields can grow and the form is resized, extra space is distributed according to the current form alignment .

PySide2.QtWidgets.QFormLayout.setFormAlignment(alignment)
Parameters

alignmentAlignment

This property holds the alignment of the form layout’s contents within the layout’s geometry.

The default value depends on the widget or application style. For QMacStyle, the default is AlignHCenter | AlignTop ; for the other styles, the default is AlignLeft | AlignTop .

PySide2.QtWidgets.QFormLayout.setHorizontalSpacing(spacing)
Parameters

spacing – int

This property holds the spacing between widgets that are laid out side by side.

By default, if no value is explicitly set, the layout’s horizontal spacing is inherited from the parent layout, or from the style settings for the parent widget.

See also

verticalSpacing pixelMetric() PM_LayoutHorizontalSpacing

PySide2.QtWidgets.QFormLayout.setItem(row, role, item)
Parameters

Sets the item in the given row for the given role to item , extending the layout with empty rows if necessary.

If the cell is already occupied, the item is not inserted and an error message is sent to the console. The item spans both columns.

Warning

Do not use this function to add child layouts or child widget items. Use setLayout() or setWidget() instead.

See also

setLayout()

PySide2.QtWidgets.QFormLayout.setLabelAlignment(alignment)
Parameters

alignmentAlignment

This property holds the horizontal alignment of the labels.

The default value depends on the widget or application style. For QCommonStyle derived styles, except for QPlastiqueStyle, the default is AlignLeft ; for the other styles, the default is AlignRight .

See also

formAlignment

PySide2.QtWidgets.QFormLayout.setLayout(row, role, layout)
Parameters

Sets the sub-layout in the given row for the given role to layout , extending the form layout with empty rows if necessary.

If the cell is already occupied, the layout is not inserted and an error message is sent to the console.

Note

For most applications, addRow() or insertRow() should be used instead of .

See also

setWidget()

PySide2.QtWidgets.QFormLayout.setRowWrapPolicy(policy)
Parameters

policyRowWrapPolicy

This property holds the way in which the form’s rows wrap.

The default value depends on the widget or application style. For Qt Extended styles, the default is WrapLongRows ; for the other styles, the default is DontWrapRows .

If you want to display each label above its associated field (instead of next to it), set this property to WrapAllRows .

PySide2.QtWidgets.QFormLayout.setVerticalSpacing(spacing)
Parameters

spacing – int

This property holds the spacing between widgets that are laid out vertically.

By default, if no value is explicitly set, the layout’s vertical spacing is inherited from the parent layout, or from the style settings for the parent widget.

See also

horizontalSpacing pixelMetric() PM_LayoutHorizontalSpacing

PySide2.QtWidgets.QFormLayout.setWidget(row, role, widget)
Parameters

Sets the widget in the given row for the given role to widget , extending the layout with empty rows if necessary.

If the cell is already occupied, the widget is not inserted and an error message is sent to the console.

Note

For most applications, addRow() or insertRow() should be used instead of .

See also

setLayout()

PySide2.QtWidgets.QFormLayout.verticalSpacing()
Return type

int

This property holds the spacing between widgets that are laid out vertically.

By default, if no value is explicitly set, the layout’s vertical spacing is inherited from the parent layout, or from the style settings for the parent widget.

See also

horizontalSpacing pixelMetric() PM_LayoutHorizontalSpacing