QLabel

The QLabel widget provides a text or image display. More

Inheritance diagram of PySide2.QtWidgets.QLabel

Synopsis

Functions

Slots

Signals

Detailed Description

../../_images/windows-label.png

QLabel is used for displaying text or an image. No user interaction functionality is provided. The visual appearance of the label can be configured in various ways, and it can be used for specifying a focus mnemonic key for another widget.

A QLabel can contain any of the following content types:

Content

Setting

Plain text

Pass a QString to setText() .

Rich text

Pass a QString that contains rich text to setText() .

A pixmap

Pass a QPixmap to setPixmap() .

A movie

Pass a QMovie to setMovie() .

A number

Pass an int or a double to setNum() , which converts the number to plain text.

Nothing

The same as an empty plain text. This is the default. Set by clear() .

Warning

When passing a QString to the constructor or calling setText() , make sure to sanitize your input, as QLabel tries to guess whether it displays the text as plain text or as rich text, a subset of HTML 4 markup. You may want to call setTextFormat() explicitly, e.g. in case you expect the text to be in plain format but cannot control the text source (for instance when displaying data loaded from the Web).

When the content is changed using any of these functions, any previous content is cleared.

By default, labels display left-aligned, vertically-centered text and images, where any tabs in the text to be displayed are automatically expanded . However, the look of a QLabel can be adjusted and fine-tuned in several ways.

The positioning of the content within the QLabel widget area can be tuned with setAlignment() and setIndent() . Text content can also wrap lines along word boundaries with setWordWrap() . For example, this code sets up a sunken panel with a two-line text in the bottom right corner (both lines being flush with the right side of the label):

label = QLabel(self)
label.setFrameStyle(QFrame.Panel | QFrame.Sunken)
label.setText("first line\nsecond line")
label.setAlignment(Qt.AlignBottom | Qt.AlignRight)

The properties and functions QLabel inherits from QFrame can also be used to specify the widget frame to be used for any given label.

A QLabel is often used as a label for an interactive widget. For this use QLabel provides a useful mechanism for adding an mnemonic (see QKeySequence ) that will set the keyboard focus to the other widget (called the QLabel ‘s “buddy”). For example:

phoneEdit = QLineEdit(self)
phoneLabel = QLabel("&Phone:", self)
phoneLabel.setBuddy(phoneEdit)

In this example, keyboard focus is transferred to the label’s buddy (the QLineEdit ) when the user presses Alt+P. If the buddy was a button (inheriting from QAbstractButton ), triggering the mnemonic would emulate a button click.

class PySide2.QtWidgets.QLabel([parent=None[, f=Qt.WindowFlags()]])

PySide2.QtWidgets.QLabel(text[, parent=None[, f=Qt.WindowFlags()]])

param f:

WindowFlags

param parent:

PySide2.QtWidgets.QWidget

param text:

str

Constructs an empty label.

The parent and widget flag f , arguments are passed to the QFrame constructor.

Constructs a label that displays the text, text .

The parent and widget flag f , arguments are passed to the QFrame constructor.

PySide2.QtWidgets.QLabel.alignment()
Return type:

Alignment

This property holds the alignment of the label’s contents.

By default, the contents of the label are left-aligned and vertically-centered.

See also

text

PySide2.QtWidgets.QLabel.buddy()
Return type:

PySide2.QtWidgets.QWidget

Returns this label’s buddy, or nullptr if no buddy is currently set.

See also

setBuddy()

PySide2.QtWidgets.QLabel.clear()

Clears any label contents.

PySide2.QtWidgets.QLabel.hasScaledContents()
Return type:

bool

This property holds whether the label will scale its contents to fill all available space..

When enabled and the label shows a pixmap, it will scale the pixmap to fill the available space.

This property’s default is false.

PySide2.QtWidgets.QLabel.hasSelectedText()
Return type:

bool

This property holds whether there is any text selected.

returns true if some or all of the text has been selected by the user; otherwise returns false .

By default, this property is false .

Note

The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

See also

selectedText()

PySide2.QtWidgets.QLabel.indent()
Return type:

int

This property holds the label’s text indent in pixels.

If a label displays text, the indent applies to the left edge if alignment() is AlignLeft , to the right edge if alignment() is AlignRight , to the top edge if alignment() is AlignTop , and to the bottom edge if alignment() is AlignBottom .

If indent is negative, or if no indent has been set, the label computes the effective indent as follows: If frameWidth() is 0, the effective indent becomes 0. If frameWidth() is greater than 0, the effective indent becomes half the width of the “x” character of the widget’s current font() .

By default, the indent is -1, meaning that an effective indent is calculating in the manner described above.

See also

alignment margin frameWidth() font()

PySide2.QtWidgets.QLabel.linkActivated(link)
Parameters:

link – str

PySide2.QtWidgets.QLabel.linkHovered(link)
Parameters:

link – str

PySide2.QtWidgets.QLabel.margin()
Return type:

int

This property holds the width of the margin.

The margin is the distance between the innermost pixel of the frame and the outermost pixel of contents.

The default margin is 0.

See also

indent

PySide2.QtWidgets.QLabel.movie()
Return type:

PySide2.QtGui.QMovie

Returns a pointer to the label’s movie, or nullptr if no movie has been set.

See also

setMovie()

Return type:

bool

Specifies whether QLabel should automatically open links using openUrl() instead of emitting the linkActivated() signal.

Note

The textInteractionFlags set on the label need to include either LinksAccessibleByMouse or LinksAccessibleByKeyboard.

The default value is false.

PySide2.QtWidgets.QLabel.picture()
Return type:

PySide2.QtGui.QPicture

Note

This function is deprecated.

New code should use the other overload which returns QPicture by-value.

This function returns the label’s picture or nullptr if the label doesn’t have a picture.

See also

setPicture()

PySide2.QtWidgets.QLabel.pixmap()
Return type:

PySide2.QtGui.QPixmap

Note

This function is deprecated.

This property holds the label’s pixmap..

Previously, Qt provided a version of pixmap() which returned the pixmap by-pointer. That version is now deprecated. To maintain compatibility with old code, you can explicitly differentiate between the by-pointer function and the by-value function:

const QPixmap *pixmapPtr = label->pixmap();
QPixmap pixmapVal = label->pixmap(Qt::ReturnByValue);

If you disable the deprecated version using the QT_DISABLE_DEPRECATED_BEFORE macro, then you can omit Qt::ReturnByValue as shown below:

QPixmap pixmapVal = label->pixmap();

If no pixmap has been set, the deprecated getter function will return nullptr .

Setting the pixmap clears any previous content. The buddy shortcut, if any, is disabled.

PySide2.QtWidgets.QLabel.selectedText()
Return type:

str

This property holds the selected text.

If there is no selected text this property’s value is an empty string.

By default, this property contains an empty string.

Note

The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

PySide2.QtWidgets.QLabel.selectionStart()
Return type:

int

returns the index of the first selected character in the label or -1 if no text is selected.

Note

The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

See also

selectedText()

PySide2.QtWidgets.QLabel.setAlignment(arg__1)
Parameters:

arg__1Alignment

This property holds the alignment of the label’s contents.

By default, the contents of the label are left-aligned and vertically-centered.

See also

text

PySide2.QtWidgets.QLabel.setBuddy(arg__1)
Parameters:

arg__1PySide2.QtWidgets.QWidget

Sets this label’s buddy to buddy .

When the user presses the shortcut key indicated by this label, the keyboard focus is transferred to the label’s buddy widget.

The buddy mechanism is only available for QLabels that contain text in which one character is prefixed with an ampersand, ‘&’. This character is set as the shortcut key. See the mnemonic() documentation for details (to display an actual ampersand, use ‘&&’).

In a dialog, you might create two data entry widgets and a label for each, and set up the geometry layout so each label is just to the left of its data entry widget (its “buddy”), for example:

nameEd  = QLineEdit(self)
nameLb  = QLabel("&Name:", self)
nameLb.setBuddy(nameEd)
phoneEd = QLineEdit(self)
phoneLb = QLabel("&Phone:", self)
phoneLb.setBuddy(phoneEd)
# (layout setup not shown)

With the code above, the focus jumps to the Name field when the user presses Alt+N, and to the Phone field when the user presses Alt+P.

To unset a previously set buddy, call this function with buddy set to nullptr.

PySide2.QtWidgets.QLabel.setIndent(arg__1)
Parameters:

arg__1 – int

This property holds the label’s text indent in pixels.

If a label displays text, the indent applies to the left edge if alignment() is AlignLeft , to the right edge if alignment() is AlignRight , to the top edge if alignment() is AlignTop , and to the bottom edge if alignment() is AlignBottom .

If indent is negative, or if no indent has been set, the label computes the effective indent as follows: If frameWidth() is 0, the effective indent becomes 0. If frameWidth() is greater than 0, the effective indent becomes half the width of the “x” character of the widget’s current font() .

By default, the indent is -1, meaning that an effective indent is calculating in the manner described above.

See also

alignment margin frameWidth() font()

PySide2.QtWidgets.QLabel.setMargin(arg__1)
Parameters:

arg__1 – int

This property holds the width of the margin.

The margin is the distance between the innermost pixel of the frame and the outermost pixel of contents.

The default margin is 0.

See also

indent

PySide2.QtWidgets.QLabel.setMovie(movie)
Parameters:

moviePySide2.QtGui.QMovie

Sets the label contents to movie . Any previous content is cleared. The label does NOT take ownership of the movie.

The buddy shortcut, if any, is disabled.

See also

movie() setBuddy()

PySide2.QtWidgets.QLabel.setNum(arg__1)
Parameters:

arg__1double

This is an overloaded function.

Sets the label contents to plain text containing the textual representation of double num . Any previous content is cleared. Does nothing if the double’s string representation is the same as the current contents of the label.

The buddy shortcut, if any, is disabled.

See also

setText() setNum() setBuddy()

PySide2.QtWidgets.QLabel.setNum(arg__1)
Parameters:

arg__1 – int

Sets the label contents to plain text containing the textual representation of integer num . Any previous content is cleared. Does nothing if the integer’s string representation is the same as the current contents of the label.

The buddy shortcut, if any, is disabled.

See also

setText() setNum() setBuddy()

Parameters:

open – bool

Specifies whether QLabel should automatically open links using openUrl() instead of emitting the linkActivated() signal.

Note

The textInteractionFlags set on the label need to include either LinksAccessibleByMouse or LinksAccessibleByKeyboard.

The default value is false.

PySide2.QtWidgets.QLabel.setPicture(arg__1)
Parameters:

arg__1PySide2.QtGui.QPicture

Sets the label contents to picture . Any previous content is cleared.

The buddy shortcut, if any, is disabled.

PySide2.QtWidgets.QLabel.setPixmap(arg__1)
Parameters:

arg__1PySide2.QtGui.QPixmap

This property holds the label’s pixmap..

Previously, Qt provided a version of pixmap() which returned the pixmap by-pointer. That version is now deprecated. To maintain compatibility with old code, you can explicitly differentiate between the by-pointer function and the by-value function:

const QPixmap *pixmapPtr = label->pixmap();
QPixmap pixmapVal = label->pixmap(Qt::ReturnByValue);

If you disable the deprecated version using the QT_DISABLE_DEPRECATED_BEFORE macro, then you can omit Qt::ReturnByValue as shown below:

QPixmap pixmapVal = label->pixmap();

If no pixmap has been set, the deprecated getter function will return nullptr .

Setting the pixmap clears any previous content. The buddy shortcut, if any, is disabled.

PySide2.QtWidgets.QLabel.setScaledContents(arg__1)
Parameters:

arg__1 – bool

This property holds whether the label will scale its contents to fill all available space..

When enabled and the label shows a pixmap, it will scale the pixmap to fill the available space.

This property’s default is false.

PySide2.QtWidgets.QLabel.setSelection(arg__1, arg__2)
Parameters:
  • arg__1 – int

  • arg__2 – int

Selects text from position start and for length characters.

Note

The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

See also

selectedText()

PySide2.QtWidgets.QLabel.setText(arg__1)
Parameters:

arg__1 – str

This property holds the label’s text.

If no text has been set this will return an empty string. Setting the text clears any previous content.

The text will be interpreted either as plain text or as rich text, depending on the text format setting; see setTextFormat() . The default setting is AutoText ; i.e. QLabel will try to auto-detect the format of the text set. See Supported HTML Subset for the definition of rich text.

If a buddy has been set, the buddy mnemonic key is updated from the new text.

Note that QLabel is well-suited to display small rich text documents, such as small documents that get their document specific settings (font, text color, link color) from the label’s palette and font properties. For large documents, use QTextEdit in read-only mode instead. QTextEdit can also provide a scroll bar when necessary.

Note

This function enables mouse tracking if text contains rich text.

PySide2.QtWidgets.QLabel.setTextFormat(arg__1)
Parameters:

arg__1TextFormat

This property holds the label’s text format.

See the TextFormat enum for an explanation of the possible options.

The default format is AutoText .

See also

text()

PySide2.QtWidgets.QLabel.setTextInteractionFlags(flags)
Parameters:

flagsTextInteractionFlags

Specifies how the label should interact with user input if it displays text.

If the flags contain LinksAccessibleByKeyboard the focus policy is also automatically set to StrongFocus . If TextSelectableByKeyboard is set then the focus policy is set to ClickFocus .

The default value is LinksAccessibleByMouse .

PySide2.QtWidgets.QLabel.setWordWrap(on)
Parameters:

on – bool

This property holds the label’s word-wrapping policy.

If this property is true then label text is wrapped where necessary at word-breaks; otherwise it is not wrapped at all.

By default, word wrap is disabled.

See also

text

PySide2.QtWidgets.QLabel.text()
Return type:

str

This property holds the label’s text.

If no text has been set this will return an empty string. Setting the text clears any previous content.

The text will be interpreted either as plain text or as rich text, depending on the text format setting; see setTextFormat() . The default setting is AutoText ; i.e. QLabel will try to auto-detect the format of the text set. See Supported HTML Subset for the definition of rich text.

If a buddy has been set, the buddy mnemonic key is updated from the new text.

Note that QLabel is well-suited to display small rich text documents, such as small documents that get their document specific settings (font, text color, link color) from the label’s palette and font properties. For large documents, use QTextEdit in read-only mode instead. QTextEdit can also provide a scroll bar when necessary.

Note

This function enables mouse tracking if text contains rich text.

PySide2.QtWidgets.QLabel.textFormat()
Return type:

TextFormat

This property holds the label’s text format.

See the TextFormat enum for an explanation of the possible options.

The default format is AutoText .

See also

text()

PySide2.QtWidgets.QLabel.textInteractionFlags()
Return type:

TextInteractionFlags

Specifies how the label should interact with user input if it displays text.

If the flags contain LinksAccessibleByKeyboard the focus policy is also automatically set to StrongFocus . If TextSelectableByKeyboard is set then the focus policy is set to ClickFocus .

The default value is LinksAccessibleByMouse .

PySide2.QtWidgets.QLabel.wordWrap()
Return type:

bool

This property holds the label’s word-wrapping policy.

If this property is true then label text is wrapped where necessary at word-breaks; otherwise it is not wrapped at all.

By default, word wrap is disabled.

See also

text