From bd0f3345a938b35ce6a12f6150373b0955b8dd12 Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Sun, 10 Jul 2011 15:24:15 -0500 Subject: Add Qt3 development HEAD version --- doc/html/qlabel.html | 420 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 420 insertions(+) create mode 100644 doc/html/qlabel.html (limited to 'doc/html/qlabel.html') diff --git a/doc/html/qlabel.html b/doc/html/qlabel.html new file mode 100644 index 0000000..7c4e487 --- /dev/null +++ b/doc/html/qlabel.html @@ -0,0 +1,420 @@ + + + + + +QLabel Class + + + + + + + +
+ +Home + | +All Classes + | +Main Classes + | +Annotated + | +Grouped Classes + | +Functions +

QLabel Class Reference

+ +

The QLabel widget provides a text or image display. +More... +

#include <qlabel.h> +

Inherits QFrame. +

List of all member functions. +

Public Members

+ +

Public Slots

+ +

Properties

+ +

Protected Members

+ +

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 accelerator 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(). 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( AlignBottom | AlignRight );
+
+ +

A QLabel is often used as a label for an interactive widget. For +this use QLabel provides a useful mechanism for adding an +accelerator key (see QAccel) that will set the keyboard focus to +the other widget (called the QLabel's "buddy"). For example: +

+    QLineEdit* phoneEdit = new QLineEdit( this, "phoneEdit" );
+    QLabel* phoneLabel = new QLabel( phoneEdit, "&Phone:", this, "phoneLabel" );
+
+ +

In this example, keyboard focus is transferred to the label's +buddy (the QLineEdit) when the user presses Alt+P. You can +also use the setBuddy() function to accomplish the same thing. +

+

See also QLineEdit, QTextEdit, QPixmap, QMovie, GUI Design Handbook: Label, Basic Widgets, and Text Related Classes. + +

Member Function Documentation

+

QLabel::QLabel ( QWidget * parent, const char * name = 0, WFlags f = 0 ) +

+Constructs an empty label. +

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

See also alignment, setFrameStyle(), and indent. + +

QLabel::QLabel ( const QString & text, QWidget * parent, const char * name = 0, WFlags f = 0 ) +

+Constructs a label that displays the text, text. +

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

See also text, alignment, setFrameStyle(), and indent. + +

QLabel::QLabel ( QWidget * buddy, const QString & text, QWidget * parent, const char * name = 0, WFlags f = 0 ) +

+Constructs a label that displays the text text. The label has a +buddy widget, buddy. +

If the text contains an underlined letter (a letter preceded by +an ampersand, &), and the text is in plain text format, when the +user presses Alt+ the underlined letter, focus is passed to the +buddy widget. +

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

See also text, setBuddy(), alignment, setFrameStyle(), and indent. + +

QLabel::~QLabel () +

+Destroys the label. + +

int QLabel::alignment () const +

Returns the alignment of the label's contents. +See the "alignment" property for details. +

bool QLabel::autoResize () const +

+ +

This function is obsolete. It is provided to keep old source working. We strongly advise against using it in new code. +

Returns TRUE if auto-resizing is enabled, or FALSE if auto-resizing +is disabled. +

Auto-resizing is disabled by default. +

See also setAutoResize(). + +

QWidget * QLabel::buddy () const +

+Returns this label's buddy, or 0 if no buddy is currently set. +

See also setBuddy(). + +

void QLabel::clear () [slot] +

+Clears any label contents. Equivalent to setText( "" ). + +

void QLabel::drawContents ( QPainter * p ) [virtual protected] +

+Draws the label contents using the painter p. + +

Reimplemented from QFrame. +

bool QLabel::hasScaledContents () const +

Returns TRUE if the label will scale its contents to fill all available space; otherwise returns FALSE. +See the "scaledContents" property for details. +

int QLabel::indent () const +

Returns the label's text indent in pixels. +See the "indent" property for details. +

QMovie * QLabel::movie () const +

+Returns a pointer to the label's movie, or 0 if no movie has been +set. +

See also setMovie(). + +

QPicture * QLabel::picture () const +

+ +

Returns the label's picture or 0 if the label doesn't have a +picture. + +

QPixmap * QLabel::pixmap () const +

Returns the label's pixmap. +See the "pixmap" property for details. +

void QLabel::setAlignment ( int ) [virtual] +

Sets the alignment of the label's contents. +See the "alignment" property for details. +

void QLabel::setAutoResize ( bool enable ) [virtual] +

This function is obsolete. It is provided to keep old source working. We strongly advise against using it in new code. +

Enables auto-resizing if enable is TRUE, or disables it if enable is FALSE. +

When auto-resizing is enabled the label will resize itself to fit +the contents whenever the contents change. The top-left corner is +not moved. This is useful for QLabel widgets that are not managed by +a QLayout (e.g., top-level widgets). +

Auto-resizing is disabled by default. +

See also autoResize(), adjustSize(), and sizeHint. + +

void QLabel::setBuddy ( QWidget * buddy ) [virtual] +

+Sets this label's buddy to buddy. +

When the user presses the accelerator 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 +plain text in which one letter is prefixed with an ampersand, &. +This letter is set as the accelerator key. The letter is displayed +underlined, and the '&' is not displayed (i.e. the ShowPrefix +alignment flag is turned on; see setAlignment()). +

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: +

+    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 )
+
+ +

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 0. +

See also buddy(), text, QAccel, and alignment. + +

Examples: addressbook/centralwidget.cpp, chart/optionsform.cpp, and regexptester/regexptester.cpp. +

void QLabel::setFont ( const QFont & f ) [virtual] +

+Sets the font used on the QLabel to font f. + +

Example: menu/menu.cpp. +

Reimplemented from QWidget. +

void QLabel::setIndent ( int ) +

Sets the label's text indent in pixels. +See the "indent" property for details. +

void QLabel::setMovie ( const QMovie & movie ) [virtual slot] +

+Sets the label contents to movie. Any previous content is +cleared. +

The buddy accelerator, if any, is disabled. +

The label resizes itself if auto-resizing is enabled. +

See also movie() and setBuddy(). + +

void QLabel::setNum ( int num ) [virtual slot] +

+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 accelerator, if any, is disabled. +

The label resizes itself if auto-resizing is enabled. +

See also text, QString::setNum(), and setBuddy(). + +

void QLabel::setNum ( double num ) [virtual slot] +

+This is an overloaded member function, provided for convenience. It behaves essentially like the above 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 accelerator, if any, is disabled. +

The label resizes itself if auto-resizing is enabled. +

See also text, QString::setNum(), and setBuddy(). + +

void QLabel::setPicture ( const QPicture & picture ) [virtual slot] +

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

The buddy accelerator, if any, is disabled. +

See also picture() and setBuddy(). + +

void QLabel::setPixmap ( const QPixmap & ) [virtual slot] +

Sets the label's pixmap. +See the "pixmap" property for details. +

void QLabel::setScaledContents ( bool ) +

Sets whether the label will scale its contents to fill all available space. +See the "scaledContents" property for details. +

void QLabel::setText ( const QString & ) [virtual slot] +

Sets the label's text. +See the "text" property for details. +

void QLabel::setTextFormat ( TextFormat ) +

Sets the label's text format. +See the "textFormat" property for details. +

QString QLabel::text () const +

Returns the label's text. +See the "text" property for details. +

TextFormat QLabel::textFormat () const +

Returns the label's text format. +See the "textFormat" property for details. +

Property Documentation

+

Alignment alignment

+

This property holds the alignment of the label's contents. +

The alignment is a bitwise OR of Qt::AlignmentFlags and Qt::TextFlags values. The ExpandTabs, SingleLine and ShowPrefix flags apply only if the label contains plain text; +otherwise they are ignored. The DontClip flag is always +ignored. WordBreak applies to both rich text and plain text +labels. The BreakAnywhere flag is not supported in QLabel. +

If the label has a buddy, the ShowPrefix flag is forced to +TRUE. +

The default alignment is AlignAuto | AlignVCenter | ExpandTabs +if the label doesn't have a buddy and AlignAuto | AlignVCenter | ExpandTabs | ShowPrefix if the label has a buddy. If the label +contains rich text, additionally WordBreak is turned on. +

See also Qt::AlignmentFlags, setBuddy(), and text. + +

Set this property's value with setAlignment() and get this property's value with alignment(). +

BackgroundMode backgroundMode

+

This property holds the label's background mode. +

Get this property with backgroundMode(). +

See also QWidget::backgroundMode. + +

int indent

+

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 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(). +

See also alignment, frameWidth, and font. + +

Set this property's value with setIndent() and get this property's value with indent(). +

QPixmap pixmap

+

This property holds the label's pixmap. +

If no pixmap has been set this will return an invalid pixmap. +

Setting the pixmap clears any previous content, and resizes the +label if QLabel::autoResize() is TRUE. The buddy accelerator, +if any, is disabled. + +

Set this property's value with setPixmap() and get this property's value with pixmap(). +

bool scaledContents

+

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. +

See also scaledContents. + +

Set this property's value with setScaledContents() and get this property's value with hasScaledContents(). +

QString text

+

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, unless they are the same. +

The text will be interpreted either as a plain text or as a 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. +

If the text is interpreted as a plain text and a buddy has been +set, the buddy accelerator key is updated from the new text. +

The label resizes itself if auto-resizing is enabled. +

Note that Qlabel is well-suited to display small rich text +documents, i.e. those 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 will flicker less on resize +and can also provide a scrollbar when necessary. +

See also textFormat, setBuddy(), and alignment. + +

Set this property's value with setText() and get this property's value with text(). +

TextFormat textFormat

+

This property holds the label's text format. +

See the Qt::TextFormat enum for an explanation of the possible +options. +

The default format is AutoText. +

See also text. + +

Set this property's value with setTextFormat() and get this property's value with textFormat(). + +

+This file is part of the Qt toolkit. +Copyright © 1995-2007 +Trolltech. All Rights Reserved.

+ +
Copyright © 2007 +TrolltechTrademarks +
Qt 3.3.8
+
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