QLineEdit¶

PyQt6.QtWidgets.QLineEdit: Inherits from QWidget.

Description¶

The QLineEdit widget is a one-line text editor.

A line edit allows users to enter and edit a single line of plain text with useful editing functions, including undo and redo, cut and paste, and drag and drop.

By changing the echoMode() of a line edit, it can also be used as a write-only field for inputs such as passwords.

QTextEdit is a related class that allows multi-line, rich text editing.

Constraining Text¶

Use maxLength() to define the maximum permitted length of a text. You can use a inputMask() and setValidator() to further constrain the text content.

Editing Text¶

You can change the text with setText() or insert(). Use text() to retrieve the text and displayText() to retrieve the displayed text (which may be different, see EchoMode). You can select the text with setSelection() or selectAll(), and you can cut(), copy(), and paste() the selection. To align the text, use setAlignment().

When the text changes, the textChanged signal is emitted. When the text changes in some other way than by calling setText(), the textEdited signal is emitted. When the cursor is moved, the cursorPositionChanged signal is emitted. And when the Return or Enter key is selected, the returnPressed signal is emitted.

When text editing is finished, either because the line edit lost focus or Return/Enter was selected, the editingFinished signal is emitted.

If the line edit focus is lost without any text changes, the editingFinished signal won’t be emitted.

If there is a validator set on the line edit, the returnPressed/editingFinished signals will only be emitted if the validator returns Acceptable.

For more information on the many ways that QLineEdit can be used, see Line Edits Example, which also provides a selection of line edit examples that show the effects of various properties and validators on the input and output supplied by the user.

Setting a Frame¶

By default, QLineEdits have a frame as specified in the platform style guides. You can turn the frame off by calling setFrame()(false).

Default Key Bindings¶

The table below describes the default key bindings.

Note: The line edit also provides a context menu (usually invoked by a right-click) that presents some of the editing options listed below.

Keystroke	Action
Left Arrow	Moves the cursor one character to the left.
Shift+Left Arrow	Moves and selects text one character to the left.
Right Arrow	Moves the cursor one character to the right.
Shift+Right Arrow	Moves and selects text one character to the right.
Home	Moves the cursor to the beginning of the line.
End	Moves the cursor to the end of the line.
Backspace	Deletes the character to the left of the cursor.
Ctrl+Backspace	Deletes the word to the left of the cursor.
Delete	Deletes the character to the right of the cursor.
Ctrl+Delete	Deletes the word to the right of the cursor.
Ctrl+A	Selects all.
Ctrl+C	Copies the selected text to the clipboard.
Ctrl+Insert	Copies the selected text to the clipboard.
Ctrl+K	Deletes to the end of the line.
Ctrl+V	Pastes the clipboard text into line edit.
Shift+Insert	Pastes the clipboard text into line edit.
Ctrl+X	Deletes the selected text and copies it to the clipboard.
Shift+Delete	Deletes the selected text and copies it to the clipboard.
Ctrl+Z	Undoes the last operation.
Ctrl+Y	Redoes the last undone operation.

Any other keystroke that represents a valid character, will cause the character to be inserted into the line edit.

Enums¶

ActionPosition

This enum type describes how a line edit should display the action widgets to be added.

See also

addAction(), removeAction(), layoutDirection().

Member	Value	Description
LeadingPosition	0	The widget is displayed to the left of the text when using layout direction `Qt::LeftToRight` or to the right when using `Qt::RightToLeft`, respectively.
TrailingPosition	1	The widget is displayed to the right of the text when using layout direction `Qt::LeftToRight` or to the left when using `Qt::RightToLeft`, respectively.

EchoMode

This enum type describes how a line edit should display its contents.

See also

setEchoMode(), echoMode().

Member	Value	Description
NoEcho	1	Do not display anything. This may be appropriate for passwords where even the length of the password should be kept secret.
Normal	0	Display characters as they are entered. This is the default.
Password	2	Display platform-dependent password mask characters instead of the characters actually entered.
PasswordEchoOnEdit	3	Display characters only while they are entered. Otherwise, display characters as with `Password`.

Methods¶

__init__(parent: QWidget = None)

Constructs a line edit with no text.

The maximum text length is set to 32767 characters.

The parent argument is sent to the QWidget constructor.

See also

setText(), setMaxLength().

__init__(Optional[str], parent: QWidget = None)

Constructs a line edit containing the text contents as a child of parent.

The cursor position is set to the end of the line and the maximum text length to 32767 characters.

See also

text(), setMaxLength().

addAction(QAction): TODO

addAction(QAction, ActionPosition): Adds the action to the list of actions at the position.

addAction(QIcon, ActionPosition) → QAction

This is an overloaded function.

Creates a new action with the given icon at the position.

alignment() → AlignmentFlag: See also

setAlignment().

backspace(): If no text is selected, deletes the character to the left of the text cursor, and moves the cursor one position to the left. If any text is selected, the cursor is moved to the beginning of the selected text, and the selected text is deleted.

See also

del_().

changeEvent(QEvent): TODO

clear(): Clears the contents of the line edit.

See also

setText(), insert().

completer() → QCompleter: Returns the current QCompleter that provides completions.

See also

setCompleter().

contextMenuEvent(QContextMenuEvent): TODO

copy(): Copies the selected text to the clipboard, if there is any, and if echoMode() is Normal.

See also

cut(), paste().

createStandardContextMenu() → QMenu: Creates the standard context menu, which is shown when the user clicks on the line edit with the right mouse button. It is called from the default contextMenuEvent() handler. The popup menu’s ownership is transferred to the caller.

cursorBackward(bool, steps: int = 1): Moves the cursor back steps characters. If mark is true each character moved over is added to the selection; if mark is false the selection is cleared.

See also

cursorForward().

cursorForward(bool, steps: int = 1): Moves the cursor forward steps characters. If mark is true each character moved over is added to the selection; if mark is false the selection is cleared.

See also

cursorBackward().

cursorMoveStyle() → CursorMoveStyle: See also

setCursorMoveStyle().

cursorPosition() → int: See also

setCursorPosition().

cursorPositionAt(QPoint) → int: Returns the cursor position under the point pos.

cursorRect() → QRect: Returns a rectangle that includes the lineedit cursor.

cursorWordBackward(bool): Moves the cursor one word backward. If mark is true, the word is also selected.

See also

cursorWordForward().

cursorWordForward(bool): Moves the cursor one word forward. If mark is true, the word is also selected.

See also

cursorWordBackward().

cut()

Copies the selected text to the clipboard and deletes it, if there is any, and if echoMode() is Normal.

If the current validator disallows deleting the selected text, cut() will copy without deleting.

See also

copy(), paste(), setValidator().

del_(): If no text is selected, deletes the character to the right of the text cursor. If any text is selected, the cursor is moved to the beginning of the selected text, and the selected text is deleted.

See also

backspace().

deselect(): Deselects any selected text.

See also

setSelection(), selectAll().

displayText() → str: TODO

dragEnabled() → bool: See also

setDragEnabled().

dragEnterEvent(QDragEnterEvent): TODO

dragLeaveEvent(QDragLeaveEvent): TODO

dragMoveEvent(QDragMoveEvent): TODO

dropEvent(QDropEvent): TODO

echoMode() → EchoMode: See also

setEchoMode().

end(bool): Moves the text cursor to the end of the line unless it is already there. If mark is true, text is selected towards the last position; otherwise, any selected text is unselected if the cursor is moved.

See also

home().

event(QEvent) → bool: TODO

focusInEvent(QFocusEvent): TODO

focusOutEvent(QFocusEvent): TODO

hasAcceptableInput() → bool: TODO

hasFrame() → bool: TODO

hasSelectedText() → bool: TODO

home(bool): Moves the text cursor to the beginning of the line unless it is already there. If mark is true, text is selected towards the first position; otherwise, any selected text is unselected if the cursor is moved.

See also

end().

initStyleOption(QStyleOptionFrame): Initialize option with the values from this QLineEdit. This method is useful for subclasses when they need a QStyleOptionFrame, but don’t want to fill in all the information themselves.

See also

initFrom().

inputMask() → str: See also

setInputMask().

inputMethodEvent(QInputMethodEvent): TODO

inputMethodQuery(InputMethodQuery) → Any: TODO

inputMethodQuery(InputMethodQuery, Any) → Any: TODO

insert(Optional[str]): Deletes any selected text, inserts newText, and validates the result. If it is valid, it sets it as the new contents of the line edit.

See also

setText(), clear().

isClearButtonEnabled() → bool: TODO

isModified() → bool: TODO

isReadOnly() → bool: TODO

isRedoAvailable() → bool: TODO

isUndoAvailable() → bool: TODO

keyPressEvent(QKeyEvent): TODO

keyReleaseEvent(QKeyEvent): TODO

maxLength() → int: See also

setMaxLength().

minimumSizeHint() → QSize: TODO

mouseDoubleClickEvent(QMouseEvent): TODO

mouseMoveEvent(QMouseEvent): TODO

mousePressEvent(QMouseEvent): TODO

mouseReleaseEvent(QMouseEvent): TODO

paintEvent(QPaintEvent): TODO

paste()

Inserts the clipboard’s text at the cursor position, deleting any selected text, providing the line edit is not read-only.

If the end result would be invalid to the current setValidator(), nothing happens.

See also

copy(), cut().

placeholderText() → str: See also

setPlaceholderText().

redo(): Redoes the last operation if redo is available.

selectAll()

Selects all the text (highlights it) and moves the cursor to the end.

Note: 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 deleted.

See also

setSelection(), deselect().

selectedText() → str: TODO

selectionEnd() → int: Returns the index of the character directly after the selection in the line edit (or -1 if no text is selected).

See also

selectedText(), selectionStart(), selectionLength().

selectionLength() → int: Returns the length of the selection.

See also

selectedText(), selectionStart(), selectionEnd().

selectionStart() → int: Returns the index of the first selected character in the line edit (or -1 if no text is selected).

See also

selectedText(), selectionEnd(), selectionLength().

setAlignment(AlignmentFlag): See also

alignment().

setClearButtonEnabled(bool): See also

isClearButtonEnabled().

setCompleter(QCompleter)

Sets this line edit to provide auto completions from the completer, c. The completion mode is set using setCompletionMode().

To use a QCompleter with a QValidator or inputMask(), you need to ensure that the model provided to QCompleter contains valid entries. You can use the QSortFilterProxyModel to ensure that the QCompleter’s model contains only valid entries.

To remove the completer and disable auto-completion, pass a nullptr.

See also

completer(), QCompleter.

setCursorMoveStyle(CursorMoveStyle): See also

cursorMoveStyle().

setCursorPosition(int): See also

cursorPosition().

setDragEnabled(bool): See also

dragEnabled().

setEchoMode(EchoMode): See also

echoMode().

setFrame(bool): See also

hasFrame().

setInputMask(Optional[str]): See also

inputMask().

setMaxLength(int): See also

maxLength().

setModified(bool): See also

isModified().

setPlaceholderText(Optional[str]): See also

placeholderText().

setReadOnly(bool): See also

isReadOnly().

setSelection(int, int): Selects text from position start and for length characters. Negative lengths are allowed.

See also

deselect(), selectAll(), selectedText().

setText(Optional[str]): See also

text().

setTextMargins(QMargins): Sets the margins around the text inside the frame.

See also

textMargins().

setTextMargins(int, int, int, int): Sets the margins around the text inside the frame to have the sizes left, top, right, and bottom.

See also

textMargins().

setValidator(QValidator)

Sets the validator for values of line edit to v.

The line edit’s returnPressed and editingFinished signals will only be emitted if v validates the line edit’s content as Acceptable. The user may change the content to any Intermediate value during editing, but will be prevented from editing the text to a value that v validates as Invalid.

This allows you to constrain the text that will be stored when editing is done while leaving users with enough freedom to edit the text from one valid state to another.

To remove the current input validator, pass nullptr. The initial setting is to have no input validator (any input is accepted up to maxLength()).

sizeHint() → QSize: TODO

text() → str: See also

setText().

textMargins() → QMargins: Returns the widget’s text margins.

See also

setTextMargins().

timerEvent(QTimerEvent): TODO

undo(): Undoes the last operation if undo is available. Deselects any current selection, and updates the selection start to the current cursor position.

validator() → QValidator: Returns a pointer to the current input validator, or nullptr if no validator has been set.

See also

setValidator().

Signals¶

cursorPositionChanged(int, int): This signal is emitted whenever the cursor moves. The previous position is given by oldPos, and the new position by newPos.

See also

setCursorPosition(), cursorPosition().

editingFinished()

This signal is emitted when the Return or Enter key is used, or if the line edit loses focus and its contents have changed since the last time this signal was emitted.

Note: If there is a validator() or inputMask() set on the line edit and enter/return is used, the editingFinished() signal will only be emitted if the input follows the inputMask() and the validator() returns Acceptable.

inputRejected()

This signal is emitted when the user uses a key that is not considered to be valid input. For example, if using a key results in a validator’s validate() call to return Invalid. Another case is when trying to enter more characters beyond the maximum length of the line edit.

Note: This signal will still be emitted when only a part of the text is accepted. For example, if there is a maximum length set and the clipboard text is longer than the maximum length when it is pasted.

returnPressed()

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

Note: If there is a validator() or inputMask() set on the line edit, the returnPressed() signal will only be emitted if the input follows the inputMask() and the validator() returns Acceptable.

selectionChanged(): This signal is emitted whenever the selection changes.

See also

hasSelectedText(), selectedText().

textChanged(Optional[str])

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

Unlike textEdited, this signal is also emitted when the text is changed programmatically, for example, by calling setText().

textEdited(Optional[str])

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

Unlike textChanged, this signal is not emitted when the text is changed programmatically, for example, by calling setText().