qlineedit.html

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This signal is emitted when the Return or Enter key is pressed.

<p>Example: <a href="popup-example.html#x1576">popup/popup.cpp</a>.
<h3 class=fn>void <a name="selectAll"></a>QLineEdit::selectAll ()<tt> [virtual slot]</tt>
</h3>
Selects all the text (i.e. highlights it) and moves the cursor to
the end. This is useful when a default value has been inserted
because if the user types before clicking on the widget, the
selected text will be erased.
<p> <p>See also <a href="#setSelection">setSelection</a>() and <a href="#deselect">deselect</a>().

<h3 class=fn><a href="qstring.html">QString</a> <a name="selectedText"></a>QLineEdit::selectedText () const
</h3><p>Returns any text selected by the user or QString::null.
See the <a href="qlineedit.html#selectedText-prop">"selectedText"</a> property for details.
<h3 class=fn>void <a name="selectionChanged"></a>QLineEdit::selectionChanged ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted whenever the selection changes.
<p> <p>See also <a href="#hasSelectedText-prop">hasSelectedText</a> and <a href="#selectedText-prop">selectedText</a>.

<h3 class=fn>void <a name="setAlignment"></a>QLineEdit::setAlignment ( int&nbsp;flag )<tt> [virtual slot]</tt>
</h3><p>Sets the alignment of the line edit to <em>flag</em>.
See the <a href="qlineedit.html#alignment-prop">"alignment"</a> property for details.
<h3 class=fn>void <a name="setCursorPosition"></a>QLineEdit::setCursorPosition ( int )<tt> [virtual slot]</tt>
</h3><p>Sets the current cursor position for this line edit.
See the <a href="qlineedit.html#cursorPosition-prop">"cursorPosition"</a> property for details.
<h3 class=fn>void <a name="setDragEnabled"></a>QLineEdit::setDragEnabled ( bool&nbsp;b )<tt> [virtual slot]</tt>
</h3><p>Sets whether the lineedit starts a drag if the user presses and moves the mouse on some selected text to <em>b</em>.
See the <a href="qlineedit.html#dragEnabled-prop">"dragEnabled"</a> property for details.
<h3 class=fn>void <a name="setEchoMode"></a>QLineEdit::setEchoMode ( <a href="qlineedit.html#EchoMode-enum">EchoMode</a> )<tt> [virtual slot]</tt>
</h3><p>Sets the echo mode of the line edit.
See the <a href="qlineedit.html#echoMode-prop">"echoMode"</a> property for details.
<h3 class=fn>void <a name="setEdited"></a>QLineEdit::setEdited ( bool )
</h3><p>Sets the edited flag of the line edit.
See the <a href="qlineedit.html#edited-prop">"edited"</a> property for details.
<h3 class=fn>void <a name="setFrame"></a>QLineEdit::setFrame ( bool )<tt> [virtual slot]</tt>
</h3><p>Sets whether the line edit draws itself with a frame.
See the <a href="qlineedit.html#frame-prop">"frame"</a> property for details.
<h3 class=fn>void <a name="setMaxLength"></a>QLineEdit::setMaxLength ( int )<tt> [virtual slot]</tt>
</h3><p>Sets the maximum permitted length of the text in the editor.
See the <a href="qlineedit.html#maxLength-prop">"maxLength"</a> property for details.
<h3 class=fn>void <a name="setPasswordChar"></a>QLineEdit::setPasswordChar ( <a href="qchar.html">QChar</a>&nbsp;c )
</h3>
Sets the password character to <em>c</em>.
<p> <p>See also <a href="#passwordChar">passwordChar</a>().

<h3 class=fn>void <a name="setReadOnly"></a>QLineEdit::setReadOnly ( bool )<tt> [virtual slot]</tt>
</h3><p>Sets whether the line edit is read only.
See the <a href="qlineedit.html#readOnly-prop">"readOnly"</a> property for details.
<h3 class=fn>void <a name="setSelection"></a>QLineEdit::setSelection ( int&nbsp;start, int&nbsp;length )<tt> [virtual slot]</tt>
</h3>  Sets the selected area of this line edit to start at position <em>start</em> and be <em>length</em> characters long.
<p> <p>See also <a href="#deselect">deselect</a>(), <a href="#selectAll">selectAll</a>() and <a href="#getSelection">getSelection</a>().

<h3 class=fn>void <a name="setText"></a>QLineEdit::setText ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp; )<tt> [virtual slot]</tt>
</h3><p>Sets the text in the line.
See the <a href="qlineedit.html#text-prop">"text"</a> property for details.
<h3 class=fn>void <a name="setValidator"></a>QLineEdit::setValidator ( const&nbsp;<a href="qvalidator.html">QValidator</a>&nbsp;*&nbsp;v )<tt> [virtual slot]</tt>
</h3>
Sets this line edit to accept input only as accepted by the
validator, <em>v</em>, allowing arbitrary constraints on the text which
may be entered.
<p> If <em>v</em> == 0, <a href="#setValidator">setValidator</a>() removes the current input validator.
The initial setting is to have no input validator (i.e. any input
is accepted up to <a href="#maxLength">maxLength</a>()).
<p> <p>See also <a href="#validator">validator</a>() and <a href="qvalidator.html">QValidator</a>.

<p>Examples: <a href="lineedits-example.html#x108">lineedits/lineedits.cpp</a> and <a href="wizard-example.html#x7">wizard/wizard.cpp</a>.
<h3 class=fn><a href="qsize.html">QSize</a> <a name="sizeHint"></a>QLineEdit::sizeHint () const<tt> [virtual]</tt>
</h3>
Returns a recommended size for the widget.
<p> The width returned, in pixels, is usually enough for about 15 to 20
characters.

<p>Example: <a href="addressbook-example.html#x532">addressbook/centralwidget.cpp</a>.
<h3 class=fn><a href="qstring.html">QString</a> <a name="text"></a>QLineEdit::text () const
</h3><p>Returns the text in the line.
See the <a href="qlineedit.html#text-prop">"text"</a> property for details.
<h3 class=fn>void <a name="textChanged"></a>QLineEdit::textChanged ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp; )<tt> [signal]</tt>
</h3>

This signal is emitted whenever the text changes.
The argument is the new text.

<p>Examples: <a href="wizard-example.html#x9">wizard/wizard.cpp</a> and <a href="xform-example.html#x1430">xform/xform.cpp</a>.
<h3 class=fn>void <a name="undo"></a>QLineEdit::undo ()<tt> [virtual slot]</tt>
</h3> Undoes the last operation 
<h3 class=fn>bool <a name="validateAndSet"></a>QLineEdit::validateAndSet ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;newText, int&nbsp;newPos, int&nbsp;newMarkAnchor, int&nbsp;newMarkDrag )
</h3>  Validates and perhaps sets this line edit to contain <em>newText</em>
with the cursor at position <em>newPos</em>, with selected text from <em>newMarkAnchor</em> to <em>newMarkDrag</em>.  Returns TRUE if it changes the line
edit; otherwise returns FALSE.
<p> Linebreaks in <em>newText</em> are converted to spaces, and the text is
truncated to <a href="#maxLength">maxLength</a>() before its validity is tested.
<p> Repaints and emits <a href="#textChanged">textChanged</a>() if appropriate.

<h3 class=fn>const&nbsp;<a href="qvalidator.html">QValidator</a>&nbsp;* <a name="validator"></a>QLineEdit::validator () const
</h3>
Returns a pointer to the current input validator, or 0 if no
validator has been set.
<p> <p>See also <a href="#setValidator">setValidator</a>().

<p>Example: <a href="wizard-example.html#x10">wizard/wizard.cpp</a>.
<hr><h2>Property Documentation</h2>
<h3 class=fn>Alignment <a name="alignment-prop"></a>alignment</h3> <p>This property holds the alignment of the line edit.
<p>Possible Values are Qt::AlignAuto, Qt::AlignLeft,
Qt::AlignRight and Qt::AlignHCenter.
<p> Attempting to set the alignment to an illegal flag combination does
nothing.
<p> <p>See also <a href="qt.html#AlignmentFlags-enum">Qt::AlignmentFlags</a>.

<p>Set this property's value with <a href="#setAlignment">setAlignment</a>() and get this property's value with <a href="#alignment">alignment</a>().
<h3 class=fn>int <a name="cursorPosition-prop"></a>cursorPosition</h3> <p>This property holds the current cursor position for this line edit.
<p>Setting the cursor position causes a repaint when appropriate.

<p>Set this property's value with <a href="#setCursorPosition">setCursorPosition</a>() and get this property's value with <a href="#cursorPosition">cursorPosition</a>().
<h3 class=fn><a href="qstring.html">QString</a> <a name="displayText-prop"></a>displayText</h3> <p>This property holds the text that is displayed.
<p>If EchoMode is Normal this returns the same as <a href="#text">text</a>(); if EchoMode
is Password it returns a string of asterisks the text().length()
characters long, e.g. "******"; if EchoMode is NoEcho returns an
empty string, "".
<p> <p>See also <a href="#echoMode-prop">echoMode</a>, <a href="#text-prop">text</a> and <a href="#EchoMode-enum">EchoMode</a>.

<p>Get this property's value with <a href="#displayText">displayText</a>().
<h3 class=fn>bool <a name="dragEnabled-prop"></a>dragEnabled</h3> <p>This property holds whether the lineedit starts a drag if the user presses and moves the mouse on some selected text.
<p>
<p>Set this property's value with <a href="#setDragEnabled">setDragEnabled</a>() and get this property's value with <a href="#dragEnabled">dragEnabled</a>().
<h3 class=fn><a href="qlineedit.html#EchoMode-enum">EchoMode</a> <a name="echoMode-prop"></a>echoMode</h3> <p>This property holds the echo mode of the line edit.
<p>The initial setting is Normal, but QLineEdit also supports NoEcho
and Password modes.
<p> The widget's display and the ability to copy or drag the text is
affected by this setting.
<p> <p>See also <a href="#EchoMode-enum">EchoMode</a> and <a href="#displayText-prop">displayText</a>.

<p>Set this property's value with <a href="#setEchoMode">setEchoMode</a>() and get this property's value with <a href="#echoMode">echoMode</a>().
<h3 class=fn>bool <a name="edited-prop"></a>edited</h3> <p>This property holds the edited flag of the line edit.
<p>The edited flag is never read by QLineEdit; it has a default value of
FALSE and is changed to TRUE whenever the user changes the line edit's
contents.
<p> This is useful for things that need to provide a default value
but cannot find the default at once.  Just start the line edit without
the best default; when the default is known, check the <a href="#edited">edited</a>()
return value and set the line edit's contents if the user has not
started editing the line edit.
<p> Calling <a href="#setText">setText</a>() resets the edited flag to FALSE.

<p>Set this property's value with <a href="#setEdited">setEdited</a>() and get this property's value with <a href="#edited">edited</a>().
<h3 class=fn>bool <a name="frame-prop"></a>frame</h3> <p>This property holds whether the line edit draws itself with a frame.
<p>If enabled (the default) the line edit draws itself inside a
two-pixel frame, otherwise the line edit draws itself without
any frame.

<p>Set this property's value with <a href="#setFrame">setFrame</a>() and get this property's value with <a href="#frame">frame</a>().
<h3 class=fn>bool <a name="hasMarkedText-prop"></a>hasMarkedText</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p> <p>This property holds whether part of the text has been selected by the user (e.g. by clicking and dragging).
<p>Get this property's value with <a href="#hasMarkedText">hasMarkedText</a>().
<p><p>See also <a href="#selectedText-prop">selectedText</a>.

<h3 class=fn>bool <a name="hasSelectedText-prop"></a>hasSelectedText</h3>
<p>This property holds whether there is any text selected.
<p>hasSelectedText() returns TRUE if some or all of the text has been
selected by the user (e.g. by clicking and dragging); otherwise
returns FALSE.
<p> <p>See also <a href="#selectedText-prop">selectedText</a>.

<p>Get this property's value with <a href="#hasSelectedText">hasSelectedText</a>().
<h3 class=fn><a href="qstring.html">QString</a> <a name="markedText-prop"></a>markedText</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p> <p>This property holds the text selected by the user (e.g. by clicking and dragging), or <a href="qstring.html#QString-null">QString::null</a> if no text is selected.
<p>Get this property's value with <a href="#markedText">markedText</a>().
<p><p>See also <a href="#hasSelectedText-prop">hasSelectedText</a>.

<h3 class=fn>int <a name="maxLength-prop"></a>maxLength</h3> <p>This property holds the maximum permitted length of the text in the editor.
<p>If the text is too long, it is truncated at the limit.
<p> If truncation occurs any selected text will be unselected, the
cursor position is set to 0 and the first part of the string is
shown.

<p>Set this property's value with <a href="#setMaxLength">setMaxLength</a>() and get this property's value with <a href="#maxLength">maxLength</a>().
<h3 class=fn>bool <a name="readOnly-prop"></a>readOnly</h3> <p>This property holds whether the line edit is read only.
<p>In read-only mode, the user can still copy the text to the
clipboard or drag-and-drop the text, but cannot edit it.
<p> QLineEdit does not show a cursor in read-only mode.
<p> <p>See also <a href="qwidget.html#enabled-prop">enabled</a>.

<p>Set this property's value with <a href="#setReadOnly">setReadOnly</a>() and get this property's value with <a href="#isReadOnly">isReadOnly</a>().
<h3 class=fn>bool <a name="redoAvailable-prop"></a>redoAvailable</h3>
<p>This property holds whether redo is available.
<p>
<p>Get this property's value with <a href="#isRedoAvailable">isRedoAvailable</a>().
<h3 class=fn><a href="qstring.html">QString</a> <a name="selectedText-prop"></a>selectedText</h3>
<p>This property holds any text selected by the user or <a href="qstring.html#QString-null">QString::null</a>.
<p>Get this property's value with <a href="#selectedText">selectedText</a>().
<p><p>See also <a href="#hasSelectedText-prop">hasSelectedText</a>.

<h3 class=fn><a href="qstring.html">QString</a> <a name="text-prop"></a>text</h3> <p>This property holds the text in the line.
<p>Setting this property clears the selection, moves the cursor to the end
of the line and resets the edited property to FALSE.
<p> The text is truncated to <a href="#maxLength">maxLength</a>() length.

<p>Set this property's value with <a href="#setText">setText</a>() and get this property's value with <a href="#text">text</a>().
<h3 class=fn>bool <a name="undoAvailable-prop"></a>undoAvailable</h3>
<p>This property holds whether undo is available.
<p>
<p>Get this property's value with <a href="#isUndoAvailable">isUndoAvailable</a>().
<!-- eof -->
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