QGIS API Documentation  2.99.0-Master (90ae728)
qgslayertreenode.cpp
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1 /***************************************************************************
2  qgslayertreenode.cpp
3  --------------------------------------
4  Date : May 2014
5  Copyright : (C) 2014 by Martin Dobias
6  Email : wonder dot sk at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
16 #include "qgslayertreenode.h"
17 
18 #include "qgslayertree.h"
19 #include "qgslayertreeutils.h"
20 
21 #include <QDomElement>
22 #include <QStringList>
23 
24 
26  : mNodeType( t )
27  , mChecked( checked )
28  , mParent( nullptr )
29  , mExpanded( true )
30 {
31 }
32 
34  : QObject()
35  , mNodeType( other.mNodeType )
36  , mChecked( other.mChecked )
37  , mParent( nullptr )
38  , mExpanded( other.mExpanded )
39  , mProperties( other.mProperties )
40 {
41  QList<QgsLayerTreeNode*> clonedChildren;
42  Q_FOREACH ( QgsLayerTreeNode* child, other.mChildren )
43  clonedChildren << child->clone();
44  insertChildrenPrivate( -1, clonedChildren );
45 }
46 
48 {
49  qDeleteAll( mChildren );
50 }
51 
53 {
54  QgsLayerTreeNode* node = nullptr;
55  if ( element.tagName() == QLatin1String( "layer-tree-group" ) )
56  node = QgsLayerTreeGroup::readXml( element );
57  else if ( element.tagName() == QLatin1String( "layer-tree-layer" ) )
58  node = QgsLayerTreeLayer::readXml( element );
59 
60  return node;
61 }
62 
63 QgsLayerTreeNode* QgsLayerTreeNode::readXml( QDomElement& element, const QgsProject* project )
64 {
65  QgsLayerTreeNode* node = readXml( element );
66  if ( node )
67  node->resolveReferences( project );
68  return node;
69 }
70 
71 
73 {
74  if ( mChecked == checked )
75  return;
76  mChecked = checked;
77  emit visibilityChanged( this );
78 }
79 
81 {
82  setItemVisibilityChecked( checked );
83 }
84 
86 {
87  setItemVisibilityChecked( checked );
88  if ( mParent )
90 }
91 
93 {
94  return mChecked && ( !mParent || mParent->isVisible() );
95 }
96 
97 
99 {
100  return mExpanded;
101 }
102 
104 {
105  if ( !mChecked )
106  return false;
107  Q_FOREACH ( QgsLayerTreeNode* child, mChildren )
108  {
109  if ( !child->isItemVisibilityCheckedRecursive() )
110  return false;
111  }
112 
113  return true;
114 }
115 
117 {
118  if ( mChecked )
119  return false;
120  Q_FOREACH ( QgsLayerTreeNode* child, mChildren )
121  {
122  if ( !child->isItemVisibilityUncheckedRecursive() )
123  return false;
124  }
125 
126  return true;
127 }
128 
129 void QgsLayerTreeNode::setExpanded( bool expanded )
130 {
131  if ( mExpanded == expanded )
132  return;
133 
134  mExpanded = expanded;
135  emit expandedChanged( this, expanded );
136 }
137 
138 
139 void QgsLayerTreeNode::setCustomProperty( const QString &key, const QVariant &value )
140 {
141  mProperties.setValue( key, value );
142  emit customPropertyChanged( this, key );
143 }
144 
145 QVariant QgsLayerTreeNode::customProperty( const QString &key, const QVariant &defaultValue ) const
146 {
147  return mProperties.value( key, defaultValue );
148 }
149 
150 void QgsLayerTreeNode::removeCustomProperty( const QString &key )
151 {
152  mProperties.remove( key );
153  emit customPropertyChanged( this, key );
154 }
155 
157 {
158  return mProperties.keys();
159 }
160 
161 void QgsLayerTreeNode::readCommonXml( QDomElement& element )
162 {
163  mProperties.readXml( element );
164 }
165 
166 void QgsLayerTreeNode::writeCommonXml( QDomElement& element )
167 {
168  QDomDocument doc( element.ownerDocument() );
169  mProperties.writeXml( element, doc );
170 }
171 
172 void QgsLayerTreeNode::insertChildrenPrivate( int index, QList<QgsLayerTreeNode*> nodes )
173 {
174  if ( nodes.isEmpty() )
175  return;
176 
177  Q_FOREACH ( QgsLayerTreeNode *node, nodes )
178  {
179  Q_ASSERT( !node->mParent );
180  node->mParent = this;
181  }
182 
183  if ( index < 0 || index >= mChildren.count() )
184  index = mChildren.count();
185 
186  int indexTo = index + nodes.count() - 1;
187  emit willAddChildren( this, index, indexTo );
188  for ( int i = 0; i < nodes.count(); ++i )
189  {
190  mChildren.insert( index + i, nodes[i] );
191 
192  // forward the signal towards the root
193  connect( nodes[i], SIGNAL( willAddChildren( QgsLayerTreeNode*, int, int ) ), this, SIGNAL( willAddChildren( QgsLayerTreeNode*, int, int ) ) );
194  connect( nodes[i], SIGNAL( addedChildren( QgsLayerTreeNode*, int, int ) ), this, SIGNAL( addedChildren( QgsLayerTreeNode*, int, int ) ) );
195  connect( nodes[i], SIGNAL( willRemoveChildren( QgsLayerTreeNode*, int, int ) ), this, SIGNAL( willRemoveChildren( QgsLayerTreeNode*, int, int ) ) );
196  connect( nodes[i], SIGNAL( removedChildren( QgsLayerTreeNode*, int, int ) ), this, SIGNAL( removedChildren( QgsLayerTreeNode*, int, int ) ) );
197  connect( nodes[i], SIGNAL( customPropertyChanged( QgsLayerTreeNode*, QString ) ), this, SIGNAL( customPropertyChanged( QgsLayerTreeNode*, QString ) ) );
199  connect( nodes[i], SIGNAL( expandedChanged( QgsLayerTreeNode*, bool ) ), this, SIGNAL( expandedChanged( QgsLayerTreeNode*, bool ) ) );
200  connect( nodes[i], SIGNAL( nameChanged( QgsLayerTreeNode*, QString ) ), this, SIGNAL( nameChanged( QgsLayerTreeNode*, QString ) ) );
201  }
202  emit addedChildren( this, index, indexTo );
203 }
204 
205 void QgsLayerTreeNode::removeChildrenPrivate( int from, int count, bool destroy )
206 {
207  if ( from < 0 || count <= 0 )
208  return;
209 
210  int to = from + count - 1;
211  if ( to >= mChildren.count() )
212  return;
213  emit willRemoveChildren( this, from, to );
214  while ( --count >= 0 )
215  {
216  QgsLayerTreeNode *node = mChildren.takeAt( from );
217  node->mParent = nullptr;
218  if ( destroy )
219  delete node;
220  }
221  emit removedChildren( this, from, to );
222 }
223 
225 {
226  int index = mChildren.indexOf( node );
227  if ( index < 0 )
228  return false;
229 
230  int n = mChildren.size();
231 
232  removeChildrenPrivate( index, 1, false );
233 
234  return mChildren.size() < n;
235 }
static unsigned index
bool isItemVisibilityUncheckedRecursive() const
Return whether this node is unchecked and all its children.
void readXml(const QDomNode &parentNode, const QString &keyStartsWith=QString())
Read store contents from XML.
void insertChildrenPrivate(int index, QList< QgsLayerTreeNode *> nodes)
Low-level insertion of children to the node. The children must not have any parent yet! ...
bool takeChild(QgsLayerTreeNode *node)
Remove a child from a node.
virtual QgsLayerTreeNode * clone() const =0
Create a copy of the node. Returns new instance.
bool mExpanded
whether the node should be shown in GUI as expanded
void willRemoveChildren(QgsLayerTreeNode *node, int indexFrom, int indexTo)
Emitted when one or more nodes will be removed from a node within the tree.
bool isVisible() const
Returns whether a node is really visible (ie checked and all its ancestors checked as well) ...
QVariant value(const QString &key, const QVariant &defaultValue=QVariant()) const
Return value for the given key. If the key is not stored, default value will be used.
static QgsLayerTreeGroup * readXml(QDomElement &element)
Read group (tree) from XML element <layer-tree-group> and return the newly created group (or null on ...
void writeXml(QDomNode &parentNode, QDomDocument &doc) const
Write store contents to XML.
bool isExpanded() const
Return whether the node should be shown as expanded or collapsed in GUI.
NodeType
Enumeration of possible tree node types.
QStringList customProperties() const
Return list of keys stored in custom properties.
void remove(const QString &key)
Remove a key (entry) from the store.
void willAddChildren(QgsLayerTreeNode *node, int indexFrom, int indexTo)
Emitted when one or more nodes will be added to a node within the tree.
void removedChildren(QgsLayerTreeNode *node, int indexFrom, int indexTo)
Emitted when one or more nodes has been removed from a node within the tree.
virtual void resolveReferences(const QgsProject *project)=0
Turn textual references to layers into map layer object from project.
NodeType mNodeType
type of the node - determines which subclass is used
virtual void setItemVisibilityCheckedRecursive(bool checked)
Check or uncheck a node and all its children (taking into account exclusion rules) ...
void setValue(const QString &key, const QVariant &value)
Add an entry to the store. If the entry with the keys exists already, it will be overwritten.
void expandedChanged(QgsLayerTreeNode *node, bool expanded)
Emitted when the collapsed/expanded state of a node within the tree has been changed.
void addedChildren(QgsLayerTreeNode *node, int indexFrom, int indexTo)
Emitted when one or more nodes have been added to a node within the tree.
void writeCommonXml(QDomElement &element)
Write common XML elements.
QVariant customProperty(const QString &key, const QVariant &defaultValue=QVariant()) const
Read a custom property from layer. Properties are stored in a map and saved in project file...
static QgsLayerTreeLayer * readXml(QDomElement &element)
Read layer node from XML.
QgsLayerTreeNode * mParent
pointer to the parent node - null in case of root node
static QgsLayerTreeNode * readXml(QDomElement &element)
Read layer tree from XML.
This class is a base class for nodes in a layer tree.
Reads and writes project states.
Definition: qgsproject.h:74
QList< QgsLayerTreeNode * > mChildren
list of children - node is responsible for their deletion
void removeCustomProperty(const QString &key)
Remove a custom property from layer. Properties are stored in a map and saved in project file...
QStringList keys() const
Return list of stored keys.
void setExpanded(bool expanded)
Set whether the node should be shown as expanded or collapsed in GUI.
void setItemVisibilityCheckedParentRecursive(bool checked)
Check or uncheck a node and all its parents.
void removeChildrenPrivate(int from, int count, bool destroy=true)
Low-level removal of children from the node.
bool isItemVisibilityCheckedRecursive() const
Return whether this node is checked and all its children.
void visibilityChanged(QgsLayerTreeNode *node)
Emitted when check state of a node within the tree has been changed.
void readCommonXml(QDomElement &element)
Read common XML elements.
void setItemVisibilityChecked(bool checked)
Check or uncheck a node (independently of its ancestors or children)
void customPropertyChanged(QgsLayerTreeNode *node, const QString &key)
Emitted when a custom property of a node within the tree has been changed or removed.
void nameChanged(QgsLayerTreeNode *node, QString name)
Emitted when the name of the node is changed.
QgsLayerTreeNode(NodeType t, bool checked=true)
Constructor.
void setCustomProperty(const QString &key, const QVariant &value)
Set a custom property for the node. Properties are stored in a map and saved in project file...
QgsObjectCustomProperties mProperties
custom properties attached to the node