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The QLabel widget provides a text or image display. More...
Inherits QFrame.
The QLabel widget provides a text or image display.
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. |
When the content is changed using any of these functions, any previous content is cleared.
The look of a QLabel can be tuned in several ways. All the settings of QFrame are available for specifying a widget frame. 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 bounderies 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):
QLabel *label = new QLabel(this); label->setFrameStyle(QFrame::Panel | QFrame::Sunken); label->setText("first line\nsecond line"); label->setAlignment(Qt::AlignBottom | Qt::AlignRight);
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:
QLineEdit* phoneEdit = new QLineEdit(this); QLabel* phoneLabel = new QLabel("&Phone:", this); 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.
![]() | A label shown in the Macintosh widget style. |
![]() | A label shown in the Plastique widget style. |
![]() | A label shown in the Windows XP widget style. |
See also QLineEdit, QTextEdit, QPixmap, QMovie, and GUI Design Handbook: Label.
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