An Abstract Base Class for QGIS project property hierarchys. More...
#include <qgsprojectproperty.h>
Public Member Functions | |
| QgsProjectProperty () | |
| virtual | ~QgsProjectProperty ()=default |
| virtual void | dump (int tabs=0) const =0 |
| Dumps out the keys and values. More... | |
| virtual bool | isKey () const =0 |
Returns true if the property is a QgsProjectPropertyKey. More... | |
| virtual bool | isLeaf () const =0 |
Returns true if property is a leaf node. More... | |
| virtual bool | isValue () const =0 |
Returns true if the property is a QgsProjectPropertyValue. More... | |
| virtual bool | readXml (const QDomNode &keyNode)=0 |
| Restores the property hierarchy from a specified DOM node. More... | |
| virtual QVariant | value () const =0 |
| Returns the node's value. More... | |
| virtual bool | writeXml (const QString &nodeName, QDomElement &element, QDomDocument &document)=0 |
| Writes the property hierarchy to a specified DOM element. More... | |
Detailed Description
An Abstract Base Class for QGIS project property hierarchys.
Each sub-class is either a QgsProjectPropertyKey or QgsProjectPropertyValue. QgsProjectPropertyKey can contain either QgsProjectPropertyKey or QgsProjectPropertyValues, thus describing an hierarchy. QgsProjectPropertyValues are always graph leaves.
- Note
- This class is used internally by QgsProject. It's generally recommended that the methods in QgsProject are used to modify project properties rather than using these low-level classes.
- Since
- QGIS 3.0
Definition at line 50 of file qgsprojectproperty.h.
Constructor & Destructor Documentation
◆ QgsProjectProperty()
| QgsProjectProperty::QgsProjectProperty | ( | ) |
Definition at line 26 of file qgsprojectproperty.cpp.
◆ ~QgsProjectProperty()
|
virtualdefault |
Member Function Documentation
◆ dump()
|
pure virtual |
Dumps out the keys and values.
- Parameters
-
tabs is number of tabs to print; used for pretty-printing hierarchy
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
◆ isKey()
|
pure virtual |
Returns true if the property is a QgsProjectPropertyKey.
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
◆ isLeaf()
|
pure virtual |
Returns true if property is a leaf node.
A leaf node is a key node that has either no value or only a single value. A non-leaf node would be a key node with key sub-nodes.
This is used for entryList() and subkeyList() implementation.
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
◆ isValue()
|
pure virtual |
Returns true if the property is a QgsProjectPropertyValue.
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
◆ readXml()
|
pure virtual |
Restores the property hierarchy from a specified DOM node.
Used for restoring properties from project file
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
◆ value()
|
pure virtual |
Returns the node's value.
For QgsProjectPropertyValue nodes, this is straightforward – just return the embedded QVariant, _value. For QgsProjectPropertyKey, this means returning the QgsProjectPropertyValue _value that is keyed by its name, if it exists; i.e., QgsProjectPropertyKey "foo" will return the property value mapped to its name, "foo", in its QHash of QProperties.
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
◆ writeXml()
|
pure virtual |
Writes the property hierarchy to a specified DOM element.
Used for saving properties to project file.
- Parameters
-
nodeName the tag name associated with this element element the parent (or encompassing) property element document the overall project file Dom document
Implemented in QgsProjectPropertyKey, and QgsProjectPropertyValue.
The documentation for this class was generated from the following files:
- /build/qgis-3.20.0+99unstable/src/core/project/qgsprojectproperty.h
- /build/qgis-3.20.0+99unstable/src/core/project/qgsprojectproperty.cpp
