QLabel Class Reference
[QtGui module]

Detailed Description

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:

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):

 QLabel *label = new QLabel(this);
 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:

 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.

Property Documentation

 QLineEdit *nameEd  = new QLineEdit(this);
 QLabel    *nameLb  = new QLabel("&Name:", this);
 nameLb->setBuddy(nameEd);
 QLineEdit *phoneEd = new QLineEdit(this);
 QLabel    *phoneLb = new QLabel("&Phone:", this);
 phoneLb->setBuddy(phoneEd);
 // (layout setup not shown)