QPlainTextEdit

The QPlainTextEdit class provides a widget that is used to edit and display plain text. More

Inheritance diagram of PySide2.QtWidgets.QPlainTextEdit

Synopsis

Functions

Virtual functions

Slots

Signals

Detailed Description

Introduction and Concepts

QPlainTextEdit is an advanced viewer/editor supporting plain text. It is optimized to handle large documents and to respond quickly to user input.

QPlainText uses very much the same technology and concepts as QTextEdit , but is optimized for plain text handling.

QPlainTextEdit works on paragraphs and characters. A paragraph is a formatted string which is word-wrapped to fit into the width of the widget. By default when reading plain text, one newline signifies a paragraph. A document consists of zero or more paragraphs. Paragraphs are separated by hard line breaks. Each character within a paragraph has its own attributes, for example, font and color.

The shape of the mouse cursor on a QPlainTextEdit is IBeamCursor by default. It can be changed through the viewport() ‘s cursor property.

Using QPlainTextEdit as a Display Widget

The text is set or replaced using setPlainText() which deletes the existing text and replaces it with the text passed to setPlainText() .

Text can be inserted using the QTextCursor class or using the convenience functions insertPlainText() , appendPlainText() or paste() .

By default, the text edit wraps words at whitespace to fit within the text edit widget. The setLineWrapMode() function is used to specify the kind of line wrap you want, WidgetWidth or NoWrap if you don’t want any wrapping. If you use word wrap to the widget’s width WidgetWidth , you can specify whether to break on whitespace or anywhere with setWordWrapMode() .

The find() function can be used to find and select a given string within the text.

If you want to limit the total number of paragraphs in a QPlainTextEdit , as it is for example useful in a log viewer, then you can use the maximumBlockCount property. The combination of setMaximumBlockCount() and appendPlainText() turns QPlainTextEdit into an efficient viewer for log text. The scrolling can be reduced with the centerOnScroll() property, making the log viewer even faster. Text can be formatted in a limited way, either using a syntax highlighter (see below), or by appending html-formatted text with appendHtml() . While QPlainTextEdit does not support complex rich text rendering with tables and floats, it does support limited paragraph-based formatting that you may need in a log viewer.

Read-only Key Bindings

When QPlainTextEdit is used read-only the key bindings are limited to navigation, and text may only be selected with the mouse:

Keypresses

Action

UpArrow

Moves one line up.

DownArrow

Moves one line down.

LeftArrow

Moves one character to the left.

RightArrow

Moves one character to the right.

PageUp

Moves one (viewport) page up.

PageDown

Moves one (viewport) page down.

Home

Moves to the beginning of the text.

End

Moves to the end of the text.

Alt+Wheel

Scrolls the page horizontally (the Wheel is the mouse wheel).

Ctrl+Wheel

Zooms the text.

Ctrl+A

Selects all text.

Using QPlainTextEdit as an Editor

All the information about using QPlainTextEdit as a display widget also applies here.

Selection of text is handled by the QTextCursor class, which provides functionality for creating selections, retrieving the text contents or deleting selections. You can retrieve the object that corresponds with the user-visible cursor using the textCursor() method. If you want to set a selection in QPlainTextEdit just create one on a QTextCursor object and then make that cursor the visible cursor using setCursor() . The selection can be copied to the clipboard with copy() , or cut to the clipboard with cut() . The entire text can be selected using selectAll() .

QPlainTextEdit holds a QTextDocument object which can be retrieved using the document() method. You can also set your own document object using setDocument() . QTextDocument emits a textChanged() signal if the text changes and it also provides a isModified() function which will return true if the text has been modified since it was either loaded or since the last call to setModified with false as argument. In addition it provides methods for undo and redo.

Syntax Highlighting

Just like QTextEdit , QPlainTextEdit works together with QSyntaxHighlighter .

Editing Key Bindings

The list of key bindings which are implemented for editing:

Keypresses

Action

Backspace

Deletes the character to the left of the cursor.

Delete

Deletes the character to the right of the cursor.

Ctrl+C

Copy the selected text to the clipboard.

Ctrl+Insert

Copy the selected text to the clipboard.

Ctrl+K

Deletes to the end of the line.

Ctrl+V

Pastes the clipboard text into text edit.

Shift+Insert

Pastes the clipboard text into text 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 operation.

LeftArrow

Moves the cursor one character to the left.

Ctrl+LeftArrow

Moves the cursor one word to the left.

RightArrow

Moves the cursor one character to the right.

Ctrl+RightArrow

Moves the cursor one word to the right.

UpArrow

Moves the cursor one line up.

Ctrl+UpArrow

Moves the cursor one word up.

DownArrow

Moves the cursor one line down.

Ctrl+Down Arrow

Moves the cursor one word down.

PageUp

Moves the cursor one page up.

PageDown

Moves the cursor one page down.

Home

Moves the cursor to the beginning of the line.

Ctrl+Home

Moves the cursor to the beginning of the text.

End

Moves the cursor to the end of the line.

Ctrl+End

Moves the cursor to the end of the text.

Alt+Wheel

Scrolls the page horizontally (the Wheel is the mouse wheel).

Ctrl+Wheel

Zooms the text.

To select (mark) text hold down the Shift key whilst pressing one of the movement keystrokes, for example, Shift+Right Arrow will select the character to the right, and Shift+Ctrl+Right Arrow will select the word to the right, etc.

Differences to QTextEdit

QPlainTextEdit is a thin class, implemented by using most of the technology that is behind QTextEdit and QTextDocument . Its performance benefits over QTextEdit stem mostly from using a different and simplified text layout called QPlainTextDocumentLayout on the text document (see setDocumentLayout() ). The plain text document layout does not support tables nor embedded frames, and replaces a pixel-exact height calculation with a line-by-line respectively paragraph-by-paragraph scrolling approach . This makes it possible to handle significantly larger documents, and still resize the editor with line wrap enabled in real time. It also makes for a fast log viewer (see setMaximumBlockCount() ).

See also

QTextDocument QTextCursor Application Example Code Editor Example Syntax Highlighter Example Rich Text Processing

class QPlainTextEdit([parent=None])

QPlainTextEdit(text[, parent=None])

param parent

QWidget

param text

unicode

Constructs an empty QPlainTextEdit with parent parent .

PySide2.QtWidgets.QPlainTextEdit.LineWrapMode

Constant

Description

QPlainTextEdit.NoWrap

QPlainTextEdit.WidgetWidth

PySide2.QtWidgets.QPlainTextEdit.anchorAt(pos)
Parameters

posQPoint

Return type

unicode

Returns the reference of the anchor at position pos , or an empty string if no anchor exists at that point.

PySide2.QtWidgets.QPlainTextEdit.appendHtml(html)
Parameters

html – unicode

Appends a new paragraph with html to the end of the text edit.

appendPlainText()

PySide2.QtWidgets.QPlainTextEdit.appendPlainText(text)
Parameters

text – unicode

Appends a new paragraph with text to the end of the text edit.

See also

appendHtml()

PySide2.QtWidgets.QPlainTextEdit.backgroundVisible()
Return type

bool

PySide2.QtWidgets.QPlainTextEdit.blockBoundingGeometry(block)
Parameters

blockQTextBlock

Return type

QRectF

Returns the bounding rectangle of the text block in content coordinates. Translate the rectangle with the contentOffset() to get visual coordinates on the viewport.

PySide2.QtWidgets.QPlainTextEdit.blockBoundingRect(block)
Parameters

blockQTextBlock

Return type

QRectF

Returns the bounding rectangle of the text block in the block’s own coordinates.

PySide2.QtWidgets.QPlainTextEdit.blockCount()
Return type

int

PySide2.QtWidgets.QPlainTextEdit.blockCountChanged(newBlockCount)
Parameters

newBlockCountint

PySide2.QtWidgets.QPlainTextEdit.canInsertFromMimeData(source)
Parameters

sourceQMimeData

Return type

bool

This function returns true if the contents of the MIME data object, specified by source , can be decoded and inserted into the document. It is called for example when during a drag operation the mouse enters this widget and it is necessary to determine whether it is possible to accept the drag.

PySide2.QtWidgets.QPlainTextEdit.canPaste()
Return type

bool

Returns whether text can be pasted from the clipboard into the textedit.

PySide2.QtWidgets.QPlainTextEdit.centerCursor()

Scrolls the document in order to center the cursor vertically.

PySide2.QtWidgets.QPlainTextEdit.centerOnScroll()
Return type

bool

PySide2.QtWidgets.QPlainTextEdit.clear()

Deletes all the text in the text edit.

Notes:

PySide2.QtWidgets.QPlainTextEdit.contentOffset()
Return type

QPointF

Returns the content’s origin in viewport coordinates.

The origin of the content of a plain text edit is always the top left corner of the first visible text block. The content offset is different from (0,0) when the text has been scrolled horizontally, or when the first visible block has been scrolled partially off the screen, i.e. the visible text does not start with the first line of the first visible block, or when the first visible block is the very first block and the editor displays a margin.

PySide2.QtWidgets.QPlainTextEdit.copy()

Copies any selected text to the clipboard.

See also

copyAvailable()

PySide2.QtWidgets.QPlainTextEdit.copyAvailable(b)
Parameters

bbool

PySide2.QtWidgets.QPlainTextEdit.createMimeDataFromSelection()
Return type

QMimeData

This function returns a new MIME data object to represent the contents of the text edit’s current selection. It is called when the selection needs to be encapsulated into a new QMimeData object; for example, when a drag and drop operation is started, or when data is copied to the clipboard.

If you reimplement this function, note that the ownership of the returned QMimeData object is passed to the caller. The selection can be retrieved by using the textCursor() function.

PySide2.QtWidgets.QPlainTextEdit.createStandardContextMenu()
Return type

QMenu

This function creates the standard context menu which is shown when the user clicks on the text edit with the right mouse button. It is called from the default contextMenuEvent() handler. The popup menu’s ownership is transferred to the caller.

We recommend that you use the ( QPoint ) version instead which will enable the actions that are sensitive to where the user clicked.

PySide2.QtWidgets.QPlainTextEdit.createStandardContextMenu(position)
Parameters

positionQPoint

Return type

QMenu

This function creates the standard context menu which is shown when the user clicks on the text edit with the right mouse button. It is called from the default contextMenuEvent() handler and it takes the position in document coordinates where the mouse click was. This can enable actions that are sensitive to the position where the user clicked. The popup menu’s ownership is transferred to the caller.

PySide2.QtWidgets.QPlainTextEdit.currentCharFormat()
Return type

QTextCharFormat

Returns the char format that is used when inserting new text.

PySide2.QtWidgets.QPlainTextEdit.cursorForPosition(pos)
Parameters

posQPoint

Return type

QTextCursor

returns a QTextCursor at position pos (in viewport coordinates).

PySide2.QtWidgets.QPlainTextEdit.cursorPositionChanged()
PySide2.QtWidgets.QPlainTextEdit.cursorRect(cursor)
Parameters

cursorQTextCursor

Return type

QRect

returns a rectangle (in viewport coordinates) that includes the cursor .

PySide2.QtWidgets.QPlainTextEdit.cursorRect()
Return type

QRect

returns a rectangle (in viewport coordinates) that includes the cursor of the text edit.

PySide2.QtWidgets.QPlainTextEdit.cursorWidth()
Return type

int

See also

setCursorWidth()

PySide2.QtWidgets.QPlainTextEdit.cut()

Copies the selected text to the clipboard and deletes it from the text edit.

If there is no selected text nothing happens.

See also

copy() paste()

PySide2.QtWidgets.QPlainTextEdit.doSetTextCursor(cursor)
Parameters

cursorQTextCursor

This provides a hook for subclasses to intercept cursor changes.

PySide2.QtWidgets.QPlainTextEdit.document()
Return type

QTextDocument

Returns a pointer to the underlying document.

See also

setDocument()

PySide2.QtWidgets.QPlainTextEdit.documentTitle()
Return type

unicode

PySide2.QtWidgets.QPlainTextEdit.ensureCursorVisible()

Ensures that the cursor is visible by scrolling the text edit if necessary.

PySide2.QtWidgets.QPlainTextEdit.extraSelections()
Return type

Returns previously set extra selections.

PySide2.QtWidgets.QPlainTextEdit.find(exp[, options=QTextDocument.FindFlags()])
Parameters
  • expQRegExp

  • optionsFindFlags

Return type

bool

PySide2.QtWidgets.QPlainTextEdit.find(exp[, options=QTextDocument.FindFlags()])
Parameters
  • expQRegularExpression

  • optionsFindFlags

Return type

bool

PySide2.QtWidgets.QPlainTextEdit.find(exp[, options=QTextDocument.FindFlags()])
Parameters
  • exp – unicode

  • optionsFindFlags

Return type

bool

PySide2.QtWidgets.QPlainTextEdit.firstVisibleBlock()
Return type

QTextBlock

Returns the first visible block.

PySide2.QtWidgets.QPlainTextEdit.getPaintContext()
Return type

PaintContext

Returns the paint context for the viewport() , useful only when reimplementing paintEvent() .

PySide2.QtWidgets.QPlainTextEdit.inputMethodQuery(query, argument)
Parameters
  • queryInputMethodQuery

  • argument – object

Return type

object

PySide2.QtWidgets.QPlainTextEdit.insertFromMimeData(source)
Parameters

sourceQMimeData

This function inserts the contents of the MIME data object, specified by source , into the text edit at the current cursor position. It is called whenever text is inserted as the result of a clipboard paste operation, or when the text edit accepts data from a drag and drop operation.

PySide2.QtWidgets.QPlainTextEdit.insertPlainText(text)
Parameters

text – unicode

Convenience slot that inserts text at the current cursor position.

It is equivalent to

edit.textCursor().insertText(text)
PySide2.QtWidgets.QPlainTextEdit.isReadOnly()
Return type

bool

PySide2.QtWidgets.QPlainTextEdit.isUndoRedoEnabled()
Return type

bool

PySide2.QtWidgets.QPlainTextEdit.lineWrapMode()
Return type

LineWrapMode

PySide2.QtWidgets.QPlainTextEdit.loadResource(type, name)
Parameters
  • typeint

  • nameQUrl

Return type

object

Loads the resource specified by the given type and name .

This function is an extension of loadResource() .

See also

loadResource()

PySide2.QtWidgets.QPlainTextEdit.maximumBlockCount()
Return type

int

PySide2.QtWidgets.QPlainTextEdit.mergeCurrentCharFormat(modifier)
Parameters

modifierQTextCharFormat

Merges the properties specified in modifier into the current character format by calling mergeCharFormat on the editor’s cursor. If the editor has a selection then the properties of modifier are directly applied to the selection.

See also

mergeCharFormat()

PySide2.QtWidgets.QPlainTextEdit.modificationChanged(arg__1)
Parameters

arg__1bool

PySide2.QtWidgets.QPlainTextEdit.moveCursor(operation[, mode=QTextCursor.MoveAnchor])
Parameters
  • operationMoveOperation

  • modeMoveMode

Moves the cursor by performing the given operation .

If mode is KeepAnchor , the cursor selects the text it moves over. This is the same effect that the user achieves when they hold down the Shift key and move the cursor with the cursor keys.

See also

movePosition()

PySide2.QtWidgets.QPlainTextEdit.overwriteMode()
Return type

bool

PySide2.QtWidgets.QPlainTextEdit.paste()

Pastes the text from the clipboard into the text edit at the current cursor position.

If there is no text in the clipboard nothing happens.

To change the behavior of this function, i.e. to modify what QPlainTextEdit can paste and how it is being pasted, reimplement the virtual canInsertFromMimeData() and insertFromMimeData() functions.

See also

cut() copy()

PySide2.QtWidgets.QPlainTextEdit.placeholderText()
Return type

unicode

PySide2.QtWidgets.QPlainTextEdit.print_(printer)
Parameters

printerQPagedPaintDevice

Convenience function to print the text edit’s document to the given printer . This is equivalent to calling the print method on the document directly except that this function also supports Selection as print range.

See also

print()

PySide2.QtWidgets.QPlainTextEdit.redo()

Redoes the last operation.

If there is no operation to redo, i.e. there is no redo step in the undo/redo history, nothing happens.

See also

undo()

PySide2.QtWidgets.QPlainTextEdit.redoAvailable(b)
Parameters

bbool

PySide2.QtWidgets.QPlainTextEdit.selectAll()

Selects all text.

PySide2.QtWidgets.QPlainTextEdit.selectionChanged()
PySide2.QtWidgets.QPlainTextEdit.setBackgroundVisible(visible)
Parameters

visiblebool

PySide2.QtWidgets.QPlainTextEdit.setCenterOnScroll(enabled)
Parameters

enabledbool

See also

centerOnScroll()

PySide2.QtWidgets.QPlainTextEdit.setCurrentCharFormat(format)
Parameters

formatQTextCharFormat

Sets the char format that is be used when inserting new text to format by calling setCharFormat() on the editor’s cursor. If the editor has a selection then the char format is directly applied to the selection.

PySide2.QtWidgets.QPlainTextEdit.setCursorWidth(width)
Parameters

widthint

See also

cursorWidth()

PySide2.QtWidgets.QPlainTextEdit.setDocument(document)
Parameters

documentQTextDocument

Makes document the new document of the text editor.

The parent QObject of the provided document remains the owner of the object. If the current document is a child of the text editor, then it is deleted.

The document must have a document layout that inherits QPlainTextDocumentLayout (see setDocumentLayout() ).

See also

document()

PySide2.QtWidgets.QPlainTextEdit.setDocumentTitle(title)
Parameters

title – unicode

See also

documentTitle()

PySide2.QtWidgets.QPlainTextEdit.setExtraSelections(selections)
Parameters

selections

This function allows temporarily marking certain regions in the document with a given color, specified as selections . This can be useful for example in a programming editor to mark a whole line of text with a given background color to indicate the existence of a breakpoint.

See also

ExtraSelection extraSelections()

PySide2.QtWidgets.QPlainTextEdit.setLineWrapMode(mode)
Parameters

modeLineWrapMode

See also

lineWrapMode()

PySide2.QtWidgets.QPlainTextEdit.setMaximumBlockCount(maximum)
Parameters

maximumint

PySide2.QtWidgets.QPlainTextEdit.setOverwriteMode(overwrite)
Parameters

overwritebool

See also

overwriteMode()

PySide2.QtWidgets.QPlainTextEdit.setPlaceholderText(placeholderText)
Parameters

placeholderText – unicode

PySide2.QtWidgets.QPlainTextEdit.setPlainText(text)
Parameters

text – unicode

Changes the text of the text edit to the string text . Any previous text is removed.

text is interpreted as plain text.

Notes:

See also

toPlainText()

PySide2.QtWidgets.QPlainTextEdit.setReadOnly(ro)
Parameters

robool

See also

isReadOnly()

PySide2.QtWidgets.QPlainTextEdit.setTabChangesFocus(b)
Parameters

bbool

PySide2.QtWidgets.QPlainTextEdit.setTabStopDistance(distance)
Parameters

distanceqreal

PySide2.QtWidgets.QPlainTextEdit.setTabStopWidth(width)
Parameters

widthint

Note

This function is deprecated.

See also

tabStopWidth()

PySide2.QtWidgets.QPlainTextEdit.setTextCursor(cursor)
Parameters

cursorQTextCursor

Sets the visible cursor .

See also

textCursor()

PySide2.QtWidgets.QPlainTextEdit.setTextInteractionFlags(flags)
Parameters

flagsTextInteractionFlags

PySide2.QtWidgets.QPlainTextEdit.setUndoRedoEnabled(enable)
Parameters

enablebool

PySide2.QtWidgets.QPlainTextEdit.setWordWrapMode(policy)
Parameters

policyWrapMode

See also

wordWrapMode()

PySide2.QtWidgets.QPlainTextEdit.tabChangesFocus()
Return type

bool

PySide2.QtWidgets.QPlainTextEdit.tabStopDistance()
Return type

qreal

PySide2.QtWidgets.QPlainTextEdit.tabStopWidth()
Return type

int

Note

This function is deprecated.

PySide2.QtWidgets.QPlainTextEdit.textChanged()
PySide2.QtWidgets.QPlainTextEdit.textCursor()
Return type

QTextCursor

Returns a copy of the QTextCursor that represents the currently visible cursor. Note that changes on the returned cursor do not affect QPlainTextEdit ‘s cursor; use setTextCursor() to update the visible cursor.

See also

setTextCursor()

PySide2.QtWidgets.QPlainTextEdit.textInteractionFlags()
Return type

TextInteractionFlags

PySide2.QtWidgets.QPlainTextEdit.toPlainText()
Return type

unicode

Returns the text of the text edit as plain text.

See also

setPlainText()

PySide2.QtWidgets.QPlainTextEdit.undo()

Undoes the last operation.

If there is no operation to undo, i.e. there is no undo step in the undo/redo history, nothing happens.

See also

redo()

PySide2.QtWidgets.QPlainTextEdit.undoAvailable(b)
Parameters

bbool

PySide2.QtWidgets.QPlainTextEdit.updateRequest(rect, dy)
Parameters
  • rectQRect

  • dyint

PySide2.QtWidgets.QPlainTextEdit.wordWrapMode()
Return type

WrapMode

PySide2.QtWidgets.QPlainTextEdit.zoomIn([range=1])
Parameters

rangeint

Zooms in on the text by making the base font size range points larger and recalculating all font sizes to be the new size. This does not change the size of any images.

See also

zoomOut()

PySide2.QtWidgets.QPlainTextEdit.zoomInF(range)
Parameters

rangefloat

PySide2.QtWidgets.QPlainTextEdit.zoomOut([range=1])
Parameters

rangeint

Zooms out on the text by making the base font size range points smaller and recalculating all font sizes to be the new size. This does not change the size of any images.

See also

zoomIn()