QHelpEngineCore

The QHelpEngineCore class provides the core functionality of the help system. More

Inheritance diagram of PySide2.QtHelp.QHelpEngineCore

Inherited by: QHelpEngine

Synopsis

Functions

Signals

Static functions

Detailed Description

Before the help engine can be used, it must be initialized by calling setupData() . At the beginning of the setup process the signal setupStarted() is emitted. From this point on until the signal setupFinished() is emitted, is the help data in an undefined meaning unusable state.

The core help engine can be used to perform different tasks. By calling linksForIdentifier() the engine returns URLs specifying the file locations inside the help system. The actual file data can then be retrived by calling fileData() . In contrast to all other functions in this class, linksForIdentifier() depends on the currently set custom filter. Depending on the filter, the function may return different results.

The help engine can contain any number of custom filters. The management of the filters, including adding new filters, changing filter definitions, or removing existing filters, is done through the QHelpFilterEngine class, which can be accessed by the filterEngine() method. This replaces older filter API that is deprecated since Qt 5.13. Please call setUsesFilterEngine() with true to enable the new functionality.

The help engine also offers the possibility to set and read values in a persistant way comparable to ini files or Windows registry entries. For more information see setValue() or value().

This class does not offer any GUI components or functionality for indices or contents. If you need one of those use QHelpEngine instead.

When creating a custom help viewer the viewer can be configured by writing a custom collection file which could contain various keywords to be used to configure the help engine. These keywords and values and their meaning can be found in the help information for creating a custom help collection file for Assistant.

class QHelpEngineCore(collectionFile[, parent=None])
param parent

QObject

param collectionFile

unicode

Constructs a new core help engine with a parent . The help engine uses the information stored in the collectionFile to provide help. If the collection file does not exist yet, it’ll be created.

PySide2.QtHelp.QHelpEngineCore.addCustomFilter(filterName, attributes)
Parameters
  • filterName – unicode

  • attributes – list of strings

Return type

bool

setFilterData() should be used instead.

Adds the new custom filter filterName . The filter attributes are specified by attributes . If the filter already exists, its attribute set is replaced. The function returns true if the operation succeeded, otherwise it returns false.

PySide2.QtHelp.QHelpEngineCore.autoSaveFilter()
Return type

bool

PySide2.QtHelp.QHelpEngineCore.collectionFile()
Return type

unicode

PySide2.QtHelp.QHelpEngineCore.copyCollectionFile(fileName)
Parameters

fileName – unicode

Return type

bool

Creates the file fileName and copies all contents from the current collection file into the newly created file, and returns true if successful; otherwise returns false.

The copying process makes sure that file references to Qt Collection files (.qch ) files are updated accordingly.

PySide2.QtHelp.QHelpEngineCore.currentFilter()
Return type

unicode

PySide2.QtHelp.QHelpEngineCore.currentFilterChanged(newFilter)
Parameters

newFilter – unicode

PySide2.QtHelp.QHelpEngineCore.customFilters()
Return type

list of strings

filters() should be used instead.

Returns a list of custom filters.

PySide2.QtHelp.QHelpEngineCore.customValue(key[, defaultValue=None])
Parameters
  • key – unicode

  • defaultValue – object

Return type

object

Returns the value assigned to the key . If the requested key does not exist, the specified defaultValue is returned.

PySide2.QtHelp.QHelpEngineCore.documentationFileName(namespaceName)
Parameters

namespaceName – unicode

Return type

unicode

Returns the absolute file name of the Qt compressed help file (.qch) identified by the namespaceName . If there is no Qt compressed help file with the specified namespace registered, an empty string is returned.

See also

namespaceName()

PySide2.QtHelp.QHelpEngineCore.error()
Return type

unicode

Returns a description of the last error that occurred.

PySide2.QtHelp.QHelpEngineCore.fileData(url)
Parameters

urlQUrl

Return type

QByteArray

Returns the data of the file specified by url . If the file does not exist, an empty QByteArray is returned.

See also

findFile()

PySide2.QtHelp.QHelpEngineCore.files(namespaceName, filterName[, extensionFilter=""])
Parameters
  • namespaceName – unicode

  • filterName – unicode

  • extensionFilter – unicode

Return type

PySide2.QtHelp.QHelpEngineCore.files(namespaceName, filterAttributes[, extensionFilter=""])
Parameters
  • namespaceName – unicode

  • filterAttributes – list of strings

  • extensionFilter – unicode

Return type

PySide2.QtHelp.QHelpEngineCore.filterAttributeSets(namespaceName)
Parameters

namespaceName – unicode

Return type

filterData() should be used instead.

Returns a list of filter attributes for the different filter sections defined in the Qt compressed help file with the given namespace namespaceName .

PySide2.QtHelp.QHelpEngineCore.filterAttributes()
Return type

list of strings

availableComponents() should be used instead.

Returns a list of all defined filter attributes.

PySide2.QtHelp.QHelpEngineCore.filterAttributes(filterName)
Parameters

filterName – unicode

Return type

list of strings

filterData() should be used instead.

Returns a list of filter attributes used by the custom filter filterName .

PySide2.QtHelp.QHelpEngineCore.filterEngine()
Return type

QHelpFilterEngine

Returns the filter engine associated with this help engine. The filter engine allows for adding, changing, and removing existing filters for this help engine. To use the engine you also have to call setUsesFilterEngine() set to true .

PySide2.QtHelp.QHelpEngineCore.findFile(url)
Parameters

urlQUrl

Return type

QUrl

Returns the corrected URL for the url that may refer to a different namespace defined by the virtual folder defined as a part of the url . If the virtual folder matches the namespace of the url , the method just checks if the file exists and returns the same url . When the virtual folder doesn’t match the namespace of the url , it tries to find the best matching namespace according to the active filter. When the namespace is found, it returns the corrected URL if the file exists, otherwise it returns an invalid URL.

PySide2.QtHelp.QHelpEngineCore.linksForIdentifier(id)
Parameters

id – unicode

Return type

Returns a map of the documents found for the id . The map contains the document titles and their URLs. The returned map contents depend on the current filter, and therefore only the identifiers registered for the current filter will be returned.

PySide2.QtHelp.QHelpEngineCore.linksForKeyword(keyword)
Parameters

keyword – unicode

Return type

Returns a map of all the documents found for the keyword . The map contains the document titles and URLs. The returned map contents depend on the current filter, and therefore only the keywords registered for the current filter will be returned.

static PySide2.QtHelp.QHelpEngineCore.metaData(documentationFileName, name)
Parameters
  • documentationFileName – unicode

  • name – unicode

Return type

object

Returns the meta data for the Qt compressed help file documentationFileName . If there is no data available for name , an invalid QVariant() is returned. The meta data is defined when creating the Qt compressed help file and cannot be modified later. Common meta data includes e.g. the author of the documentation.

static PySide2.QtHelp.QHelpEngineCore.namespaceName(documentationFileName)
Parameters

documentationFileName – unicode

Return type

unicode

Returns the namespace name defined for the Qt compressed help file (.qch) specified by its documentationFileName . If the file is not valid, an empty string is returned.

PySide2.QtHelp.QHelpEngineCore.readersAboutToBeInvalidated()
PySide2.QtHelp.QHelpEngineCore.registerDocumentation(documentationFileName)
Parameters

documentationFileName – unicode

Return type

bool

Registers the Qt compressed help file (.qch) contained in the file documentationFileName . One compressed help file, uniquely identified by its namespace can only be registered once. True is returned if the registration was successful, otherwise false.

PySide2.QtHelp.QHelpEngineCore.registeredDocumentations()
Return type

list of strings

Returns a list of all registered Qt compressed help files of the current collection file. The returned names are the namespaces of the registered Qt compressed help files (.qch).

PySide2.QtHelp.QHelpEngineCore.removeCustomFilter(filterName)
Parameters

filterName – unicode

Return type

bool

removeFilter() should be used instead.

Returns true if the filter filterName was removed successfully, otherwise false.

PySide2.QtHelp.QHelpEngineCore.removeCustomValue(key)
Parameters

key – unicode

Return type

bool

Removes the key from the settings section in the collection file. Returns true if the value was removed successfully, otherwise false.

PySide2.QtHelp.QHelpEngineCore.setAutoSaveFilter(save)
Parameters

savebool

See also

autoSaveFilter()

PySide2.QtHelp.QHelpEngineCore.setCollectionFile(fileName)
Parameters

fileName – unicode

See also

collectionFile()

PySide2.QtHelp.QHelpEngineCore.setCurrentFilter(filterName)
Parameters

filterName – unicode

See also

currentFilter()

PySide2.QtHelp.QHelpEngineCore.setCustomValue(key, value)
Parameters
  • key – unicode

  • value – object

Return type

bool

Save the value under the key . If the key already exist, the value will be overwritten. Returns true if the value was saved successfully, otherwise false.

PySide2.QtHelp.QHelpEngineCore.setUsesFilterEngine(uses)
Parameters

usesbool

Enables or disables the new filter engine functionality inside the help engine, according to the passed uses parameter.

PySide2.QtHelp.QHelpEngineCore.setupData()
Return type

bool

Sets up the help engine by processing the information found in the collection file and returns true if successful; otherwise returns false.

By calling the function, the help engine is forced to initialize itself immediately. Most of the times, this function does not have to be called explicitly because getter functions which depend on a correctly set up help engine do that themselves.

Note

qsqlite4.dll needs to be deployed with the application as the help system uses the sqlite driver when loading help collections.

PySide2.QtHelp.QHelpEngineCore.setupFinished()
PySide2.QtHelp.QHelpEngineCore.setupStarted()
PySide2.QtHelp.QHelpEngineCore.unregisterDocumentation(namespaceName)
Parameters

namespaceName – unicode

Return type

bool

Unregisters the Qt compressed help file (.qch) identified by its namespaceName from the help collection. Returns true on success, otherwise false.

PySide2.QtHelp.QHelpEngineCore.usesFilterEngine()
Return type

bool

Returns whether the help engine uses the new filter functionality.

PySide2.QtHelp.QHelpEngineCore.warning(msg)
Parameters

msg – unicode