QLineEdit(3qt)QLineEdit(3qt)NAMEQLineEdit - One-line text editor
#include <qlineedit.h>
Inherits QWidget.
Public Members
QLineEdit ( QWidget * parent, const char * name=0 )
QLineEdit ( const QString &, QWidget * parent, const char
* name=0 )
~QLineEdit ()
QString text () const
QString displayText () const
int maxLength () const
virtual void setMaxLength ( int )
virtual void setFrame ( bool )
bool frame () const
enum EchoMode { Normal, NoEcho, Password }
virtual void setEchoMode ( EchoMode )
EchoMode echoMode () const
void setReadOnly ( bool )
bool isReadOnly () const
virtual void setValidator ( const QValidator * )
const QValidator* validator () const
virtual QSize sizeHint () const
virtual QSize minimumSizeHint () const
virtual void setSelection ( int, int )
virtual void setCursorPosition ( int )
int cursorPosition () const
bool validateAndSet ( const QString &, int, int, int )
void cut ()
void copy () const
void paste ()
void setAlignment ( int flag )
int alignment () const
void cursorLeft ( bool mark, int steps = 1 )
void cursorRight ( bool mark, int steps = 1 )
void cursorWordForward ( bool mark )
void cursorWordBackward ( bool mark )
void backspace ()
void del ()
void home ( bool mark )
void end ( bool mark )
void setEdited ( bool )
bool edited () const
bool hasMarkedText () const
QString markedText () const
Public Slots
virtual void setText ( const QString & )
void selectAll ()
void deselect ()
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void clearValidator ()
void insert ( const QString & )
void clear ()
Signals
void textChanged ( const QString & )
void returnPressed ()
Protected Members
virtual void keyPressEvent ( QKeyEvent * )
void repaintArea ( int, int )
Properties
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Type Name READ WRITE Options
QString text text setText
int maxLength maxLength setMaxLength
bool frame frame setFrame
EchoMode echoMode echoMode setEchoMode
QString displayText displayText
int cursorPosition cursorPosition setCursorPosition
Alignment alignment alignment setAlignment
bool edited edited setEdited
bool hasMarkedText hasMarkedText
QString markedText markedText
DESCRIPTION
The QLineEdit widget is a one-line text editor.
A line edit allows the user to enter and edit a single
line of plain text, with a useful collection of editing
functions, including undo & redo, cut & paste, and drag &
drop.
By changing the echoMode() of a line edit it can also be
used as a "write-only" field, for inputs such as
passwords.
The length of the field can be constrained to a
maxLength(), or the value can be arbitrarily constrained
by setting a validator().
A closely related class is QMultiLineEdit which allows
multi-line editing.
The default QLineEdit object has its own frame as
specified by the Windows/Motif style guides, you can turn
off the frame by calling setFrame( FALSE ).
The default key bindings are described in keyPressEvent().
A right-mouse-button menu presents a number of the editing
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commands to the user.
[Image Omitted]
[Image Omitted]
See also QMultiLineEdit, QLabel, QComboBox, GUI Design
Handbook: Field, Entry, and GUI Design Handbook: Field,
Required.
Examples: xform/xform.cpp layout/layout.cpp
popup/popup.cpp
Member Type Documentation
QLineEdit::EchoMode
This enum type describes how QLineEdit displays its
contents. The defined values are:
Normal - display characters as they are entered. This is
the default.
NoEcho - do not display anything. This may be appropriate
for passwords where even the length of the password should
be kept secret.
Password - display asterisks instead of the characters
actually entered.
See also setEchoMode(), echoMode() and
QMultiLineEdit::EchoMode.
MEMBER FUNCTION DOCUMENTATIONQLineEdit::QLineEdit ( QWidget * parent, const char * name=0 )
Constructs a line edit with no text.
The maximum text length is set to 32767 characters.
The parent and name arguments are sent to the QWidget
constructor.
See also setText() and setMaxLength().
QLineEdit::QLineEdit ( const QString & contents, QWidget *
parent, const char * name=0 )
Constructs a line edit containing the text contents.
The cursor position is set to the end of the line and the
maximum text length to 32767 characters.
The parent and name arguments are sent to the QWidget
constructor.
See also text() and setMaxLength().
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Destructs the line edit.
int QLineEdit::alignment () const
Returns the alignment of the line edit. Possible Values
are Qt::AlignLeft, Qt::AlignRight and Qt::Align(H)Center.
See also setAlignment() and Qt::AlignmentFlags.
void QLineEdit::backspace ()
Deletes the character to the left of the text cursor and
moves the cursor one position to the left. If a text has
been marked by the user (e.g. by clicking and dragging)
the cursor will be put at the beginning of the marked text
and the marked text will be removed.
See also del().
void QLineEdit::clear () [slot]
Syntactic sugar for setText( "" ), provided to match no-
argument signals.
void QLineEdit::clearValidator () [slot]
This slot is equivalent to setValidator( 0 ).
void QLineEdit::copy () const
Copies the marked text to the clipboard, if there is any
and if echoMode() is Normal.
See also cut() and paste().
void QLineEdit::cursorLeft ( bool mark, int steps = 1 )
Moves the cursor leftwards one or more characters.
See also cursorRight().
int QLineEdit::cursorPosition () const
Returns the current cursor position for this line edit.
See also setCursorPosition().
void QLineEdit::cursorRight ( bool mark, int steps = 1 )
Moves the cursor rightwards one or more characters.
See also cursorLeft().
void QLineEdit::cursorWordBackward ( bool mark )
Moves the cursor one word to the left. If mark is TRUE,
the text is marked.
See also cursorWordForward().
void QLineEdit::cursorWordForward ( bool mark )
Moves the cursor one word to the right. If mark is TRUE,
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the text is marked.
See also cursorWordBackward().
void QLineEdit::cut ()
Copies the marked text to the clipboard and deletes it, if
there is any.
If the current validator disallows deleting the marked
text, cut() will copy it but not delete it.
See also copy() and paste().
void QLineEdit::del ()
Deletes the character on the right side of the text
cursor. If a text has been marked by the user (e.g. by
clicking and dragging) the cursor will be put at the
beginning of the marked text and the marked text will be
removed.
See also backspace().
void QLineEdit::deselect () [slot]
Deselects all text (i.e. removes marking) and leaves the
cursor at the current position.
QString QLineEdit::displayText () const
Returns the text that is displayed. This is normally the
same as text(), but can be e.g. "*****" if EchoMode is
Password or" " if it is NoEcho.
See also setEchoMode(), text() and EchoMode.
void QLineEdit::dragEnterEvent ( QDragEnterEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::dropEvent ( QDropEvent * e ) [virtual protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
QLineEdit::EchoMode QLineEdit::echoMode() const
Returns the echo mode of the line edit.
See also setEchoMode() and EchoMode.
bool QLineEdit::edited () const
Returns the edited flag of the line edit. If this returns
FALSE, the line edit's contents have not been changed
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since the construction of the QLineEdit (or the last call
to either setText() or setEdited( FALSE ), if any). If it
returns true, the contents have been edited, or setEdited(
TRUE ) has been called.
See also setEdited().
void QLineEdit::end ( bool mark )
Moves the text cursor to the right end of the line. If
mark is TRUE text will be marked towards the last
position, if not any marked text will be unmarked if the
cursor is moved.
See also home().
bool QLineEdit::event ( QEvent * e ) [virtual protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QObject.
void QLineEdit::focusInEvent ( QFocusEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::focusOutEvent ( QFocusEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
bool QLineEdit::frame () const
Returns TRUE if the line edit draws itself inside a frame,
FALSE if it draws itself without any frame.
The default is to use a frame.
See also setFrame().
bool QLineEdit::hasMarkedText () const
Returns TRUE if part of the text has been marked by the
user (e.g. by clicking and dragging).
See also markedText().
void QLineEdit::home ( bool mark )
Moves the text cursor to the left end of the line. If mark
is TRUE text will be marked towards the first position, if
not any marked text will be unmarked if the cursor is
moved.
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See also end().
void QLineEdit::insert ( const QString & newText ) [slot]
Removes any selected text, inserts newText, validates the
result and if it is valid, sets it as the new contents of
the line edit.
bool QLineEdit::isReadOnly () const
Returns whether the line-edit is read-only.
See also setReadOnly().
void QLineEdit::keyPressEvent ( QKeyEvent * e ) [virtual
protected]
Converts a key press into a line edit action.
If return or enter is pressed and the current text is
valid (or can be made valid by the validator), the signal
returnPressed is emitted.
The default key bindings are:
Left Arrow Move the cursor one character leftwards.
Right Arrow Move the cursor one character rightwards.
Backspace Delete the character to the left of the
cursor.
Home Move the cursor to the beginning of the line.
End Move the cursor to the end of the line.
Delete Delete the character to the right of the cursor.
Shift - Left Arrow Move and mark text one character
leftwards.
Shift - Right Arrow Move and mark text one character
rightwards.
Control-A Move the cursor to the beginning of the line.
Control-B Move the cursor one character leftwards.
Control-C Copy the marked text to the clipboard.
Control-D Delete the character to the right of the
cursor.
Control-E Move the cursor to the end of the line.
Control-F Move the cursor one character rightwards.
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Control-H Delete the character to the left of the
cursor.
Control-K Delete to end of line
Control-V Paste the clipboard text into line edit.
Control-X Move the marked text to the clipboard.
Control-Z Undo the last operation.
Control-Y Redo the last undone operation. In addition,
the following key bindings are used on Windows:
Shift - Delete Cut the marked text, copy to clipboard
Shift - Insert Paste the clipboard text into line edit
Control - Insert Copy the marked text to the clipboard
All other keys with valid ASCII codes insert themselves
into the line.
Reimplemented from QWidget.
void QLineEdit::leaveEvent ( QEvent * ) [virtual protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
QString QLineEdit::markedText () const
Returns the text marked by the user (e.g. by clicking and
dragging), or a null string if no text is marked.
See also hasMarkedText().
int QLineEdit::maxLength () const
Returns the maximum permitted length of the text in the
editor.
See also setMaxLength().
QSize QLineEdit::minimumSizeHint () const [virtual]
Returns a minimum size for the line edit.
The width returned is enough for at least one character.
Reimplemented from QWidget.
void QLineEdit::mouseDoubleClickEvent ( QMouseEvent * ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
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Reimplemented from QWidget.
void QLineEdit::mouseMoveEvent ( QMouseEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::mousePressEvent ( QMouseEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::mouseReleaseEvent ( QMouseEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::paintEvent ( QPaintEvent * e ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::paste ()
Inserts the clipboard's text at the cursor position,
deleting any previous marked text.
If the end result is not acceptable for the current
validator, nothing happens.
See also copy() and cut().
void QLineEdit::repaintArea ( int from, int to ) [protected]
Repaints all characters from from to to. If cursorPos is
between from and to, ensures that cursorPos is visible.
void QLineEdit::resizeEvent ( QResizeEvent * ) [virtual
protected]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
void QLineEdit::returnPressed () [signal]
This signal is emitted when the return or enter key is
pressed.
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QLineEdit(3qt)QLineEdit(3qt)void QLineEdit::selectAll () [slot]
Selects all text (i.e. marks it) and moves the cursor to
the end. This is useful when a default value has been
inserted, since if the user types before clicking on the
widget the selected text will be erased.
void QLineEdit::setAlignment ( int flag )
Sets the alignment of the line edit. Possible Values are
Qt::AlignLeft, Qt::AlignRight and Qt::Align(H)Center - see
Qt::AlignmentFlags.
See also alignment().
void QLineEdit::setCursorPosition ( int newPos ) [virtual]
Sets the cursor position for this line edit to newPos and
repaints accordingly.
See also cursorPosition().
void QLineEdit::setEchoMode ( EchoMode mode )
Sets the echo mode of the line edit widget.
The echo modes available are:
Normal - display characters as they are entered. This is
the default.
NoEcho - do not display anything. This may be appropriate
for passwords where even the length of the password should
be kept secret.
Password - display asterisks instead of the characters
actually entered.
The widget's display, and the ability to copy or drag the
text is affected by this setting.
See also echoMode(), EchoMode and displayText().
void QLineEdit::setEdited ( bool on )
Sets the edited flag of this line edit to on. The edited
flag is never read by QLineEdit, and is changed to TRUE
whenever the user changes its contents.
This is useful e.g. for things that need to provide a
default value, but cannot find the default at once. Just
open the line edit without the best default and when the
default is known, check the edited() return value and set
the line edit's contents if the user has not started
editing the line edit.
See also edited().
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QLineEdit(3qt)QLineEdit(3qt)void QLineEdit::setEnabled ( bool e ) [virtual]
Reimplemented for internal reasons; the API is not
affected.
void QLineEdit::setFont ( const QFont & f ) [virtual]
Reimplemented for internal reasons; the API is not
affected.
void QLineEdit::setFrame ( bool enable ) [virtual]
Sets the line edit to draw itself inside a frame if enable
is TRUE, and to draw itself without any frame if enable is
FALSE.
The default is TRUE.
See also frame().
void QLineEdit::setMaxLength ( int m ) [virtual]
Set the maximum length of the text in the editor. If the
text is too long, it is chopped off at the limit. Any
marked text will be unmarked. The cursor position is set
to 0 and the first part of the string is shown.
See also maxLength().
void QLineEdit::setPalette ( const QPalette & p ) [virtual]
Reimplemented for internal reasons; the API is not
affected.
void QLineEdit::setReadOnly ( bool enable )
Enables or disables read-only mode, where the user can
cut-and-paste or drag-and-drop the text, but cannot edit
it. They never see a cursor in this case.
See also setEnabled() and isReadOnly().
void QLineEdit::setSelection ( int start, int length ) [virtual]
Sets the marked area of this line edit to start at start
and be length characters long.
void QLineEdit::setText ( const QString & text ) [virtual slot]
Sets the line edit text to text, clears the selection and
moves the cursor to the end of the line.
If necessary the text is truncated to maxLength().
See also text().
Examples: xform/xform.cpp
void QLineEdit::setValidator ( const QValidator * v ) [virtual]
Sets this line edit to accept input only as accepted by v,
allowing arbitrary constraints on the text which the user
can edit.
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If v == 0, remove the current input validator. The default
is no input validator (ie. any input is accepted up to
maxLength()).
See also validator() and QValidator.
QSize QLineEdit::sizeHint () const [virtual]
Returns a recommended size for the widget.
The width returned is enough for a few characters,
typically 15 to 20.
Reimplemented from QWidget.
QSizePolicy QLineEdit::sizePolicy () const [virtual]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QWidget.
QString QLineEdit::text () const
Returns the text in the line.
See also setText().
void QLineEdit::textChanged ( const QString & ) [signal]
This signal is emitted every time the text changes. The
argument is the new text.
bool QLineEdit::validateAndSet ( const QString & newText, int
newPos, int newMarkAnchor, int newMarkDrag )
Validates and perhaps sets this line edit to contain
newText with the cursor at position newPos, with marked
text from newMarkAnchor to newMarkDrag. Returns TRUE if it
changes the line edit and FALSE if it doesn't.
Linebreaks in newText are converted to spaces, and it is
truncated to maxLength() before testing its validity.
Repaints and emits textChanged() if appropriate.
const QValidator * QLineEdit::validator () const
Returns a pointer to the current input validator, or 0 if
no validator has been set.
See also setValidator().
SEE ALSO
http://doc.trolltech.com/qlineedit.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
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in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
If you find a bug in Qt, please report it as described in
http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page (qlineedit.3qt)
and the Qt version (2.3.1).
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