The QTextDocument class holds formatted text that can be viewed and edited using a QTextEdit . 更多...
继承 QObject .
The QTextDocument class holds formatted text that can be viewed and edited using a QTextEdit .
QTextDocument is a container for structured rich text documents, providing support for styled text and various types of document elements, such as lists, tables, frames, and images. They can be created for use in a QTextEdit ，或 used independently.
Each document element is described by an associated format object. Each format object is treated as a unique object by QTextDocuments, and can be passed to objectForFormat () 到 obtain the document element that it is applied to.
A QTextDocument can be edited programmatically using a QTextCursor , and its contents can be examined by traversing the document structure. The entire document structure is stored as a hierarchy of document elements beneath the root frame, found with the rootFrame () 函数。 Alternatively, if you just want to iterate over the textual contents of the document you can use begin (), end ()，和 findBlock () to retrieve text blocks that you can examine and iterate over.
The layout of a document is determined by the documentLayout (); you can create your own QAbstractTextDocumentLayout subclass and set it using setDocumentLayout () if you want to use your own layout logic. The document's title and other meta-information can be obtained by calling the metaInformation () function. For documents that are exposed to users through the QTextEdit class, the document title is also available via the QTextEdit.documentTitle () 函数。
toPlainText () and toHtml () convenience functions allow you to retrieve the contents of the document as plain text and HTML. The document's text can be searched using the find () 函数。
Undo/redo of operations performed on the document can be controlled using the setUndoRedoEnabled () function. The undo/redo system can be controlled by an editor widget through the undo () 和 redo () slots; the document also provides contentsChanged (), undoAvailable ()，和 redoAvailable () signals that inform connected editor widgets about the state of the undo/redo system. The following are the undo/redo operations of a QTextDocument:
This enum describes the options available to QTextDocument 's find function. The options can be OR-ed together from the following list:
| 常量 | 值 | 描述 |
|---|---|---|
| QTextDocument.FindBackward | 0x00001 | Search backwards instead of forwards. |
| QTextDocument.FindCaseSensitively | 0x00002 | By default find works case insensitive. Specifying this option changes the behaviour to a case sensitive find operation. |
| QTextDocument.FindWholeWords | 0x00004 | Makes find match only complete words. |
FindFlags 类型是 typedef 对于 QFlags <FindFlag>. It stores an OR combination of FindFlag values.
This enum describes the different types of meta information that can be added to a document.
| 常量 | 值 | 描述 |
|---|---|---|
| QTextDocument.DocumentTitle | 0 | The title of the document. |
| QTextDocument.DocumentUrl | 1 | The url of the document. The loadResource () function uses this url as the base when loading relative resources. |
另请参阅 metaInformation () 和 setMetaInformation ().
This enum describes the types of resources that can be loaded by QTextDocument 's loadResource () 函数。
| 常量 | 值 | 描述 |
|---|---|---|
| QTextDocument.HtmlResource | 1 | The resource contains HTML. |
| QTextDocument.ImageResource | 2 | The resource contains image data. Currently supported data types are QVariant.Pixmap and QVariant.Image . If the corresponding variant is of type QVariant.ByteArray then Qt attempts to load the image using QImage.loadFromData. QVariant.Icon is currently not supported. The icon needs to be converted to one of the supported types first, for example using QIcon.pixmap. |
| QTextDocument.StyleSheetResource | 3 | The resource contains CSS. |
| QTextDocument.UserResource | 100 | The first available value for user defined resource types. |
另请参阅 loadResource ().
| 常量 | 值 | 描述 |
|---|---|---|
| QTextDocument.UndoStack | 0x01 | 撤消堆栈。 |
| QTextDocument.RedoStack | 0x02 | 重做堆栈。 |
| QTextDocument.UndoAndRedoStacks | UndoStack | RedoStack | 撤消和重做堆栈。 |
parent argument, if not None, causes self to be owned by Qt instead of PyQt.
构造空 QTextDocument with the given parent .
parent argument, if not None, causes self to be owned by Qt instead of PyQt.
构造 QTextDocument containing the plain (unformatted) text specified, and with the given parent .
Adds the resource resource to the resource cache, using type and name as identifiers. type should be a value from QTextDocument.ResourceType .
For example, you can add an image as a resource in order to reference it from within the document:
document->addResource(QTextDocument.ImageResource,
QUrl("mydata://image.png"), QVariant(image));
The image can be inserted into the document using the QTextCursor API:
QTextImageFormat imageFormat;
imageFormat.setName("mydata://image.png");
cursor.insertImage(imageFormat);
Alternatively, you can insert images using the HTML img tag:
editor->append("<img src=\"mydata://image.png\" />");
把文档调整到合理大小。
该函数在 Qt 4.2 引入。
另请参阅 idealWidth (), textWidth ，和 size .
Returns a vector of text formats for all the formats used in the 文档。
返回可用的重做步骤数。
该函数在 Qt 4.6 引入。
另请参阅 isRedoAvailable ().
返回可用的撤消步骤数。
该函数在 Qt 4.6 引入。
另请参阅 isUndoAvailable ().
返回文档的第一文本块。
另请参阅 firstBlock ().
返回字符位于位置 pos ，或 null character if the position is out of range.
该函数在 Qt 4.5 引入。
另请参阅 characterCount ().
返回此文档的字符数。
该函数在 Qt 4.5 引入。
另请参阅 blockCount () 和 characterAt ().
清理文档。
清零堆栈，指定通过 stacksToClear .
This method clears any commands on the undo stack, the redo stack, or both (the default). If commands are cleared, the appropriate signals are emitted, QTextDocument.undoAvailable () or QTextDocument.redoAvailable ().
该函数在 Qt 4.7 引入。
另请参阅 QTextDocument.undoAvailable () and QTextDocument.redoAvailable ().
parent argument, if not None, causes self to be owned by Qt instead of PyQt.
创建新的 QTextDocument that is a copy of this text document. parent is the parent of the returned text document.
Creates and returns a new document object (a QTextObject ), based on the given format .
QTextObjects will always get created through this method, so you must reimplement it if you use custom text objects inside your 文档。
The default cursor movement style is used by all QTextCursor objects created from the document. The default is Qt.LogicalMoveStyle .
该函数在 Qt 4.8 引入。
另请参阅 setDefaultCursorMoveStyle ().
返回此文档的文档布局。
另请参阅 setDocumentLayout ().
Draws the content of the document with painter p , clipped to rect 。若 rect is a null rectangle (default) then the document is painted unclipped.
该函数在 Qt 4.2 引入。
This function returns a block to test for the end of the document while iterating over it.
for (QTextBlock it = doc->begin(); it != doc->end(); it = it.next())
cout << it.text().toStdString() << endl;
The block returned is invalid and represents the block after the last block in the document. You can use lastBlock () to retrieve the last valid block of the document.
另请参阅 lastBlock ().
查找字符串的下一出现 subString , in the document. The search starts at the position of the given cursor , and proceeds forwards through the document unless specified otherwise in the search options. The options control the type of search performed.
Returns a cursor with the match selected if subString was found; otherwise returns a null cursor.
若给定 cursor has a selection, the search begins after the selection; otherwise it begins at the cursor's position.
By default the search is case-sensitive, and can match text anywhere in the document.
查找匹配正则表达式的下一出现 expr , in the document. The search starts at the position of the given cursor , and proceeds forwards through the document unless specified otherwise in the search options. The options control the type of search performed. The FindCaseSensitively option is ignored for this overload, use QRegExp.caseSensitivity 代替。
Returns a cursor with the match selected if a match was found; otherwise returns a null cursor.
若给定 cursor has a selection, the search begins after the selection; otherwise it begins at the cursor's position.
By default the search is case-sensitive, and can match text anywhere in the document.
这是重载函数。
查找字符串的下一出现 subString , in the document. The search starts at the given position ，和 proceeds forwards through the document unless specified otherwise in the search options. The options control the type of search performed.
Returns a cursor with the match selected if subString was found; otherwise returns a null cursor.
若 position is 0 (the default) the search begins from the beginning of the document; otherwise it begins at the specified position.
这是重载函数。
查找匹配正则表达式的下一出现 expr , in the document. The search starts at the given position , and proceeds forwards through the document unless specified otherwise in the search options. The options control the type of search performed. The FindCaseSensitively option is ignored for this overload, use QRegExp.caseSensitivity 代替。
Returns a cursor with the match selected if a match was found; otherwise returns a null cursor.
若 position is 0 (the default) the search begins from the beginning of the document; otherwise it begins at the specified position.
返回文本块包含 pos -th character.
返回文本块包含指定 lineNumber .
该函数在 Qt 4.5 引入。
另请参阅 QTextBlock.firstLineNumber ().
返回文本块采用指定 blockNumber .
该函数在 Qt 4.4 引入。
另请参阅 QTextBlock.blockNumber ().
返回文档的第一文本块。
该函数在 Qt 4.4 引入。
Returns the ideal width of the text document. The ideal width is the actually used width of the document without optional alignments taken into account. It is always <= size ().width().
该函数在 Qt 4.2 引入。
另请参阅 adjustSize () 和 textWidth .
Returns true if the document is empty; otherwise returns false.
Returns true if redo is available; otherwise returns false.
另请参阅 isUndoAvailable () 和 availableRedoSteps ().
Returns true if undo is available; otherwise returns false.
另请参阅 isRedoAvailable () 和 availableUndoSteps ().
返回文档的最后 (有效) 文本块。
该函数在 Qt 4.4 引入。
Returns the number of lines of this document (if the layout supports this). Otherwise, this is identical to the number of blocks.
该函数在 Qt 4.5 引入。
另请参阅 blockCount () 和 characterCount ().
Loads data of the specified type from the resource with the given name .
This function is called by the rich text engine to request data that isn't directly stored by QTextDocument , but still associated with it. For example, images are referenced indirectly by the name attribute of a QTextImageFormat 对象。
When called by Qt, type is one of the values of QTextDocument.ResourceType .
若 QTextDocument is a child object of a QTextEdit , QTextBrowser ，或 QTextDocument itself then the default implementation tries to retrieve the data from the parent.
Marks the contents specified by the given position and length as "dirty", informing the document that it needs to be laid out again.
Returns meta information about the document of the type 指定通过 info .
另请参阅 setMetaInformation ().
Returns the text object associated with the given objectIndex .
Returns the text object associated with the format f .
返回此文档中的页数。
Prints the document to the given printer 。 QPrinter must be set up before being used with this function.
This is only a convenience method to print the whole document to the printer.
If the document is already paginated through a specified height 在 pageSize () property it is printed as-is.
If the document is not paginated, like for example a document used in a QTextEdit , then a temporary copy of the document is created and the copy is broken into multiple pages according to the size of the QPrinter 's paperRect(). By default a 2 cm margin is set around the document contents. In addition the current page number is printed at the bottom of each page.
注意： QPrinter.Selection 不是 supported as print range with this function since the selection is a property of QTextCursor . If you have a QTextEdit associated with your QTextDocument then you can use QTextEdit 's print() function because QTextEdit has access to the user's selection.
另请参阅 QTextEdit.print ().
This method is also a Qt slot with the C++ signature void redo() .
Redoes the last editing operation on the document if redo is available .
The provided cursor is positioned at the end of the location where the edition operation was redone.
该函数在 Qt 4.2 引入。
这是重载函数。
Redoes the last editing operation on the document if redo is available .
Returns data of the specified type from the resource with the given name .
This function is called by the rich text engine to request data that isn't directly stored by QTextDocument , but still associated with it. For example, images are referenced indirectly by the name attribute of a QTextImageFormat 对象。
Resources are cached internally in the document. If a resource can not be found in the cache, loadResource is called to try to load the resource. loadResource should then use addResource to add the resource to the cache.
另请参阅 QTextDocument.ResourceType .
Returns the document's revision (if undo is enabled).
The revision is guaranteed to increase when a document that is not modified is edited.
该函数在 Qt 4.4 引入。
另请参阅 QTextBlock.revision () 和 isModified ().
Returns the document's root frame.
Sets the default cursor movement style to the given style .
该函数在 Qt 4.8 引入。
另请参阅 defaultCursorMoveStyle ().
layout argument has it's ownership transferred to Qt.
Sets the document to use the given layout . The previous layout is deleted.
另请参阅 documentLayoutChanged ().
Replaces the entire contents of the document with the given HTML-formatted text in the html string.
The HTML formatting is respected as much as possible; for example, "<b>bold</b> text" will produce text where the first word has a font weight that gives it a bold appearance: " bold text".
注意： It is the responsibility of the caller to make sure that the text is correctly decoded when a QString containing HTML is created and passed to setHtml().
另请参阅 setPlainText () 和 支持的 HTML 子集 .
Sets the document's meta information of the type specified by info 到给定 string .
另请参阅 metaInformation ().
This method is also a Qt slot with the C++ signature void setModified(bool = 1) .
Replaces the entire contents of the document with the given plain text .
另请参阅 setHtml ().
Returns a string containing an HTML representation of the 文档。
encoding parameter specifies the value for the charset attribute in the html header. For example if 'utf-8' is specified then the beginning of the generated html will look like this:
<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body>...
If no encoding is specified then no such meta information is generated.
If you later on convert the returned html string into a byte array for transmission over a network or when saving to disk you should specify the encoding you're going to use for the conversion to a byte array here.
另请参阅 支持 HTML Subset .
Returns the plain text contained in the document. If you want formatting information use a QTextCursor 代替。
另请参阅 toHtml ().
This method is also a Qt slot with the C++ signature void undo() .
Undoes the last editing operation on the document if undo is available. The provided cursor is positioned at the end of the location where the edition operation was undone.
见 Qt Undo Framework 文档编制 了解细节。
该函数在 Qt 4.2 引入。
另请参阅 undoAvailable () 和 isUndoRedoEnabled ().
这是重载函数。
This is the default overload of this signal.
This signal is emitted when the total number of text blocks in the document changes. The value passed in newBlockCount is the new total.
该函数在 Qt 4.3 引入。
This is the default overload of this signal.
This signal is emitted whenever the document's content changes; for example, when text is inserted or deleted, or when formatting is applied.
Information is provided about the position 的 character in the document where the change occurred, the number of characters removed ( charsRemoved ), and the number of characters added ( charsAdded ).
The signal is emitted before the document's layout manager is notified about the change. This hook allows you to implement syntax highlighting for the document.
另请参阅 QAbstractTextDocumentLayout.documentChanged () and contentsChanged ().
This is the default overload of this signal.
This signal is emitted whenever the document's content changes; for example, when text is inserted or deleted, or when formatting is applied.
另请参阅 contentsChange ().
This is the default overload of this signal.
This signal is emitted whenever the position of a cursor changed due to an editing operation. The cursor that changed is passed in cursor . If you need a signal when the cursor is moved with the arrow keys you can use the cursorPositionChanged() 信号在 QTextEdit .
This is the default overload of this signal.
This signal is emitted when a new document layout is set.
该函数在 Qt 4.4 引入。
另请参阅 setDocumentLayout ().
This is the default overload of this signal.
This signal is emitted whenever the content of the document changes in a way that affects the modification state. If changed is true, the document has been modified; otherwise it is false.
For example, calling setModified(false) on a document and then inserting text causes the signal to get emitted. If you undo that operation, causing the document to return to its original unmodified state, the signal will get emitted again.
This is the default overload of this signal.
This signal is emitted whenever redo operations become available ( available is true) or unavailable ( available is false).
This is the default overload of this signal.
This signal is emitted whenever undo operations become available ( available is true) or unavailable ( available is false).
见 Qt Undo Framework 文档编制 了解细节。
另请参阅 undo () 和 isUndoRedoEnabled ().
This is the default overload of this signal.
This signal is emitted every time a new level of undo is added 到 QTextDocument .
该函数在 Qt 4.4 引入。