QGIS API Documentation  2.99.0-Master (314842d)
qgslayertreeview.cpp
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1 /***************************************************************************
2  qgslayertreeview.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 "qgslayertreeview.h"
17 
18 #include "qgslayertree.h"
20 #include "qgslayertreemodel.h"
23 #include "qgsmaplayer.h"
24 
25 #include <QMenu>
26 #include <QContextMenuEvent>
27 
28 
30  : QTreeView( parent )
31  , mDefaultActions( nullptr )
32  , mMenuProvider( nullptr )
33 {
34  setHeaderHidden( true );
35 
36  setDragEnabled( true );
37  setAcceptDrops( true );
38  setDropIndicatorShown( true );
39  setEditTriggers( EditKeyPressed );
40  setExpandsOnDoubleClick( false ); // normally used for other actions
41 
42  setSelectionMode( ExtendedSelection );
43  setDefaultDropAction( Qt::MoveAction );
44 
45  connect( this, SIGNAL( collapsed( QModelIndex ) ), this, SLOT( updateExpandedStateToNode( QModelIndex ) ) );
46  connect( this, SIGNAL( expanded( QModelIndex ) ), this, SLOT( updateExpandedStateToNode( QModelIndex ) ) );
47 }
48 
50 {
51  delete mMenuProvider;
52 }
53 
54 void QgsLayerTreeView::setModel( QAbstractItemModel *model )
55 {
56  if ( !qobject_cast<QgsLayerTreeModel *>( model ) )
57  return;
58 
59  connect( model, SIGNAL( rowsInserted( QModelIndex, int, int ) ), this, SLOT( modelRowsInserted( QModelIndex, int, int ) ) );
60  connect( model, SIGNAL( rowsRemoved( QModelIndex, int, int ) ), this, SLOT( modelRowsRemoved() ) );
61 
62  QTreeView::setModel( model );
63 
64  connect( layerTreeModel()->rootGroup(), SIGNAL( expandedChanged( QgsLayerTreeNode *, bool ) ), this, SLOT( onExpandedChanged( QgsLayerTreeNode *, bool ) ) );
65 
66  connect( selectionModel(), SIGNAL( currentChanged( QModelIndex, QModelIndex ) ), this, SLOT( onCurrentChanged() ) );
67 
68  connect( layerTreeModel(), SIGNAL( modelReset() ), this, SLOT( onModelReset() ) );
69 
71 }
72 
74 {
75  return qobject_cast<QgsLayerTreeModel *>( model() );
76 }
77 
79 {
80  if ( !mDefaultActions )
82  return mDefaultActions;
83 }
84 
86 {
87  delete mMenuProvider;
89 }
90 
92 {
93  return layerForIndex( currentIndex() );
94 }
95 
97 {
98  if ( !layer )
99  {
100  setCurrentIndex( QModelIndex() );
101  return;
102  }
103 
104  QgsLayerTreeLayer *nodeLayer = layerTreeModel()->rootGroup()->findLayer( layer->id() );
105  if ( !nodeLayer )
106  return;
107 
108  setCurrentIndex( layerTreeModel()->node2index( nodeLayer ) );
109 }
110 
111 
112 void QgsLayerTreeView::contextMenuEvent( QContextMenuEvent *event )
113 {
114  if ( !mMenuProvider )
115  return;
116 
117  QModelIndex idx = indexAt( event->pos() );
118  if ( !idx.isValid() )
119  setCurrentIndex( QModelIndex() );
120 
121  QMenu *menu = mMenuProvider->createContextMenu();
122  if ( menu && menu->actions().count() != 0 )
123  menu->exec( mapToGlobal( event->pos() ) );
124  delete menu;
125 }
126 
127 
128 void QgsLayerTreeView::modelRowsInserted( const QModelIndex &index, int start, int end )
129 {
130  QgsLayerTreeNode *parentNode = layerTreeModel()->index2node( index );
131  if ( !parentNode )
132  return;
133 
134  // Embedded widgets - replace placeholders in the model by actual widgets
135  if ( layerTreeModel()->testFlag( QgsLayerTreeModel::UseEmbeddedWidgets ) && QgsLayerTree::isLayer( parentNode ) )
136  {
137  QgsLayerTreeLayer *nodeLayer = QgsLayerTree::toLayer( parentNode );
138  if ( QgsMapLayer *layer = nodeLayer->layer() )
139  {
140  int widgetsCount = layer->customProperty( QStringLiteral( "embeddedWidgets/count" ), 0 ).toInt();
141  QList<QgsLayerTreeModelLegendNode *> legendNodes = layerTreeModel()->layerLegendNodes( nodeLayer, true );
142  for ( int i = 0; i < widgetsCount; ++i )
143  {
144  QString providerId = layer->customProperty( QStringLiteral( "embeddedWidgets/%1/id" ).arg( i ) ).toString();
145  if ( QgsLayerTreeEmbeddedWidgetProvider *provider = QgsLayerTreeEmbeddedWidgetRegistry::instance()->provider( providerId ) )
146  {
147  QModelIndex index = layerTreeModel()->legendNode2index( legendNodes[i] );
148  setIndexWidget( index, provider->createWidget( layer, i ) );
149  }
150  }
151  }
152  }
153 
154 
155  if ( QgsLayerTree::isLayer( parentNode ) )
156  {
157  // if ShowLegendAsTree flag is enabled in model, we may need to expand some legend nodes
158  QStringList expandedNodeKeys = parentNode->customProperty( QStringLiteral( "expandedLegendNodes" ) ).toStringList();
159  if ( expandedNodeKeys.isEmpty() )
160  return;
161 
162  Q_FOREACH ( QgsLayerTreeModelLegendNode *legendNode, layerTreeModel()->layerLegendNodes( QgsLayerTree::toLayer( parentNode ), true ) )
163  {
164  QString ruleKey = legendNode->data( QgsLayerTreeModelLegendNode::RuleKeyRole ).toString();
165  if ( expandedNodeKeys.contains( ruleKey ) )
166  setExpanded( layerTreeModel()->legendNode2index( legendNode ), true );
167  }
168  return;
169  }
170 
171  QList<QgsLayerTreeNode *> children = parentNode->children();
172  for ( int i = start; i <= end; ++i )
173  {
174  updateExpandedStateFromNode( children[i] );
175  }
176 
177  // make sure we still have correct current layer
179 }
180 
182 {
183  // make sure we still have correct current layer
185 }
186 
188 {
189  if ( QgsLayerTreeNode *node = layerTreeModel()->index2node( index ) )
190  {
191  node->setExpanded( isExpanded( index ) );
192  }
193  else if ( QgsLayerTreeModelLegendNode *node = layerTreeModel()->index2legendNode( index ) )
194  {
195  QString ruleKey = node->data( QgsLayerTreeModelLegendNode::RuleKeyRole ).toString();
196  QStringList lst = node->layerNode()->customProperty( QStringLiteral( "expandedLegendNodes" ) ).toStringList();
197  bool expanded = isExpanded( index );
198  bool isInList = lst.contains( ruleKey );
199  if ( expanded && !isInList )
200  {
201  lst.append( ruleKey );
202  node->layerNode()->setCustomProperty( QStringLiteral( "expandedLegendNodes" ), lst );
203  }
204  else if ( !expanded && isInList )
205  {
206  lst.removeAll( ruleKey );
207  node->layerNode()->setCustomProperty( QStringLiteral( "expandedLegendNodes" ), lst );
208  }
209  }
210 }
211 
213 {
214  QgsMapLayer *layerCurrent = layerForIndex( currentIndex() );
215  QString layerCurrentID = layerCurrent ? layerCurrent->id() : QString();
216  if ( mCurrentLayerID == layerCurrentID )
217  return;
218 
219  // update the current index in model (the item will be underlined)
220  QModelIndex nodeLayerIndex;
221  if ( layerCurrent )
222  {
223  QgsLayerTreeLayer *nodeLayer = layerTreeModel()->rootGroup()->findLayer( layerCurrentID );
224  if ( nodeLayer )
225  nodeLayerIndex = layerTreeModel()->node2index( nodeLayer );
226  }
227  layerTreeModel()->setCurrentIndex( nodeLayerIndex );
228 
229  mCurrentLayerID = layerCurrentID;
230  emit currentLayerChanged( layerCurrent );
231 }
232 
234 {
235  QModelIndex idx = layerTreeModel()->node2index( node );
236  if ( isExpanded( idx ) != expanded )
237  setExpanded( idx, expanded );
238 }
239 
241 {
243 }
244 
246 {
247  QModelIndex idx = layerTreeModel()->node2index( node );
248  setExpanded( idx, node->isExpanded() );
249 
250  Q_FOREACH ( QgsLayerTreeNode *child, node->children() )
252 }
253 
255 {
256  QgsLayerTreeNode *node = layerTreeModel()->index2node( index );
257  if ( node )
258  {
259  if ( QgsLayerTree::isLayer( node ) )
260  return QgsLayerTree::toLayer( node )->layer();
261  }
262  else
263  {
264  // possibly a legend node
266  if ( legendNode )
267  return legendNode->layerNode()->layer();
268  }
269 
270  return nullptr;
271 }
272 
274 {
275  return layerTreeModel()->index2node( selectionModel()->currentIndex() );
276 }
277 
279 {
280  QgsLayerTreeNode *node = currentNode();
281  if ( QgsLayerTree::isGroup( node ) )
282  return QgsLayerTree::toGroup( node );
283  else if ( QgsLayerTree::isLayer( node ) )
284  {
285  QgsLayerTreeNode *parent = node->parent();
286  if ( QgsLayerTree::isGroup( parent ) )
287  return QgsLayerTree::toGroup( parent );
288  }
289 
290  if ( QgsLayerTreeModelLegendNode *legendNode = layerTreeModel()->index2legendNode( selectionModel()->currentIndex() ) )
291  {
292  QgsLayerTreeLayer *parent = legendNode->layerNode();
293  if ( QgsLayerTree::isGroup( parent->parent() ) )
294  return QgsLayerTree::toGroup( parent->parent() );
295  }
296 
297  return nullptr;
298 }
299 
301 {
302  return layerTreeModel()->index2legendNode( selectionModel()->currentIndex() );
303 }
304 
305 QList<QgsLayerTreeNode *> QgsLayerTreeView::selectedNodes( bool skipInternal ) const
306 {
307  return layerTreeModel()->indexes2nodes( selectionModel()->selectedIndexes(), skipInternal );
308 }
309 
310 QList<QgsLayerTreeLayer *> QgsLayerTreeView::selectedLayerNodes() const
311 {
312  QList<QgsLayerTreeLayer *> layerNodes;
313  Q_FOREACH ( QgsLayerTreeNode *node, selectedNodes() )
314  {
315  if ( QgsLayerTree::isLayer( node ) )
316  layerNodes << QgsLayerTree::toLayer( node );
317  }
318  return layerNodes;
319 }
320 
321 QList<QgsMapLayer *> QgsLayerTreeView::selectedLayers() const
322 {
323  QList<QgsMapLayer *> list;
324  Q_FOREACH ( QgsLayerTreeLayer *node, selectedLayerNodes() )
325  {
326  if ( node->layer() )
327  list << node->layer();
328  }
329  return list;
330 }
331 
332 
333 void QgsLayerTreeView::refreshLayerSymbology( const QString &layerId )
334 {
335  QgsLayerTreeLayer *nodeLayer = layerTreeModel()->rootGroup()->findLayer( layerId );
336  if ( nodeLayer )
337  layerTreeModel()->refreshLayerLegend( nodeLayer );
338 }
339 
340 
341 static void _expandAllLegendNodes( QgsLayerTreeLayer *nodeLayer, bool expanded, QgsLayerTreeModel *model )
342 {
343  // for layers we also need to find out with legend nodes contain some children and make them expanded/collapsed
344  // if we are collapsing, we just write out an empty list
345  QStringList lst;
346  if ( expanded )
347  {
348  Q_FOREACH ( QgsLayerTreeModelLegendNode *legendNode, model->layerLegendNodes( nodeLayer, true ) )
349  {
350  QString parentKey = legendNode->data( QgsLayerTreeModelLegendNode::ParentRuleKeyRole ).toString();
351  if ( !parentKey.isEmpty() && !lst.contains( parentKey ) )
352  lst << parentKey;
353  }
354  }
355  nodeLayer->setCustomProperty( "expandedLegendNodes", lst );
356 }
357 
358 
359 static void _expandAllNodes( QgsLayerTreeGroup *parent, bool expanded, QgsLayerTreeModel *model )
360 {
361  Q_FOREACH ( QgsLayerTreeNode *node, parent->children() )
362  {
363  node->setExpanded( expanded );
364  if ( QgsLayerTree::isGroup( node ) )
365  _expandAllNodes( QgsLayerTree::toGroup( node ), expanded, model );
366  else if ( QgsLayerTree::isLayer( node ) )
367  _expandAllLegendNodes( QgsLayerTree::toLayer( node ), expanded, model );
368  }
369 }
370 
371 
373 {
374  // unfortunately expandAll() does not emit expanded() signals
375  _expandAllNodes( layerTreeModel()->rootGroup(), true, layerTreeModel() );
376  expandAll();
377 }
378 
380 {
381  // unfortunately collapseAll() does not emit collapsed() signals
382  _expandAllNodes( layerTreeModel()->rootGroup(), false, layerTreeModel() );
383  collapseAll();
384 }
385 
386 void QgsLayerTreeView::mouseReleaseEvent( QMouseEvent *event )
387 {
388  const QgsLayerTreeModel::Flags oldFlags = layerTreeModel()->flags();
389  if ( event->modifiers() & Qt::ControlModifier )
391  else
393  QTreeView::mouseReleaseEvent( event );
394  layerTreeModel()->setFlags( oldFlags );
395 }
396 
397 void QgsLayerTreeView::keyPressEvent( QKeyEvent *event )
398 {
399  const QgsLayerTreeModel::Flags oldFlags = layerTreeModel()->flags();
400  if ( event->modifiers() & Qt::ControlModifier )
402  else
404  QTreeView::keyPressEvent( event );
405  layerTreeModel()->setFlags( oldFlags );
406 }
Layer tree group node serves as a container for layers and further groups.
static unsigned index
static QgsLayerTreeLayer * toLayer(QgsLayerTreeNode *node)
Cast node to a layer.
Definition: qgslayertree.h:74
QList< QgsMapLayer * > selectedLayers() const
Get list of selected layers.
Base class for all map layer types.
Definition: qgsmaplayer.h:52
Implementation of this interface can be implemented to allow QgsLayerTreeView instance to provide cus...
static bool isGroup(QgsLayerTreeNode *node)
Check whether the node is a valid group node.
Definition: qgslayertree.h:42
void setCurrentIndex(const QModelIndex &currentIndex)
Set index of the current item. May be used by view. Item marked as current is underlined.
QList< QgsLayerTreeNode * > indexes2nodes(const QModelIndexList &list, bool skipInternal=false) const
Convert a list of indexes to a list of layer tree nodes.
QgsLayerTreeViewMenuProvider * mMenuProvider
Context menu provider. Owned by the view.
static void _expandAllLegendNodes(QgsLayerTreeLayer *nodeLayer, bool expanded, QgsLayerTreeModel *model)
void refreshLayerSymbology(const QString &layerId)
Force refresh of layer symbology. Normally not needed as the changes of layer&#39;s renderer are monitore...
void contextMenuEvent(QContextMenuEvent *event) override
static QgsLayerTreeGroup * toGroup(QgsLayerTreeNode *node)
Cast node to a group.
Definition: qgslayertree.h:63
QgsLayerTreeLayer * layerNode() const
Return pointer to the parent layer node.
void modelRowsInserted(const QModelIndex &index, int start, int end)
QgsMapLayer * currentLayer() const
Get currently selected layer. May be null.
QgsLayerTreeViewDefaultActions * defaultActions()
Get access to the default actions that may be used with the tree view.
bool isExpanded() const
Return whether the node should be shown as expanded or collapsed in GUI.
QModelIndex node2index(QgsLayerTreeNode *node) const
Return index for a given node. If the node does not belong to the layer tree, the result is undefined...
virtual QMenu * createContextMenu()=0
Return a newly created menu instance (or null pointer on error)
void setFlags(QgsLayerTreeModel::Flags f)
Set OR-ed combination of model flags.
QList< QgsLayerTreeLayer * > selectedLayerNodes() const
Return list of selected nodes filtered to just layer nodes.
void mouseReleaseEvent(QMouseEvent *event) override
QString mCurrentLayerID
Keeps track of current layer ID (to check when to emit signal about change of current layer) ...
The QgsLayerTreeViewDefaultActions class serves as a factory of actions that can be used together wit...
The QgsLayerTreeModel class is model implementation for Qt item views framework.
Rule key of the parent legend node - for legends with tree hierarchy (QString). Added in 2...
void updateExpandedStateToNode(const QModelIndex &index)
QString id() const
Returns the layer&#39;s unique ID, which is used to access this layer from QgsProject.
QList< QgsLayerTreeNode * > children()
Get list of children of the node. Children are owned by the parent.
QModelIndex legendNode2index(QgsLayerTreeModelLegendNode *legendNode)
Return index for a given legend node.
Provider interface to be implemented in order to introduce new kinds of embedded widgets for use in l...
static QgsLayerTreeModelLegendNode * index2legendNode(const QModelIndex &index)
Return legend node for given index.
QgsLayerTreeNode * parent()
Get pointer to the parent. If parent is a null pointer, the node is a root node.
QgsLayerTreeGroup * currentGroupNode() const
Get current group node. If a layer is current node, the function will return parent group...
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 bool isLayer(const QgsLayerTreeNode *node)
Check whether the node is a valid layer node.
Definition: qgslayertree.h:52
This class is a base class for nodes in a layer tree.
void collapseAllNodes()
Enhancement of QTreeView::collapseAll() that also records expanded state in layer tree nodes...
void keyPressEvent(QKeyEvent *event) override
void currentLayerChanged(QgsMapLayer *layer)
Emitted when a current layer is changed.
QgsLayerTreeModel * layerTreeModel() const
Get access to the model casted to QgsLayerTreeModel.
void refreshLayerLegend(QgsLayerTreeLayer *nodeLayer)
Force a refresh of legend nodes of a layer node.
QgsLayerTreeViewDefaultActions * mDefaultActions
helper class with default actions. Lazily initialized.
void setExpanded(bool expanded)
Set whether the node should be shown as expanded or collapsed in GUI.
QgsMapLayer * layer() const
Qt::ItemFlags flags(const QModelIndex &index) const override
void updateExpandedStateFromNode(QgsLayerTreeNode *node)
QList< QgsLayerTreeNode * > selectedNodes(bool skipInternal=false) const
Return list of selected nodes.
QgsLayerTreeNode * index2node(const QModelIndex &index) const
Return layer tree node for given index.
QgsLayerTree * rootGroup() const
Return pointer to the root node of the layer tree. Always a non-null pointer.
void onExpandedChanged(QgsLayerTreeNode *node, bool expanded)
Layer nodes may optionally include extra embedded widgets (if used in QgsLayerTreeView). Added in 2.16.
QgsLayerTreeModelLegendNode * currentLegendNode() const
Get current legend node.
QgsLayerTreeViewMenuProvider * menuProvider() const
Return pointer to the context menu provider. May be null.
virtual QVariant data(int role) const =0
Return data associated with the item. Must be implemented in derived class.
QgsMapLayer * layerForIndex(const QModelIndex &index) const
The QgsLegendRendererItem class is abstract interface for legend items returned from QgsMapLayerLegen...
static QgsLayerTreeEmbeddedWidgetRegistry * instance()
Means of accessing canonical single instance.
Check/uncheck action has consequences on children (or parents for leaf node)
virtual void setModel(QAbstractItemModel *model) override
Overridden setModel() from base class. Only QgsLayerTreeModel is an acceptable model.
QList< QgsLayerTreeModelLegendNode * > layerLegendNodes(QgsLayerTreeLayer *nodeLayer, bool skipNodeEmbeddedInParent=false)
Return filtered list of active legend nodes attached to a particular layer node (by default it return...
void setCurrentLayer(QgsMapLayer *layer)
Set currently selected layer. Null pointer will deselect any layer.
QgsLayerTreeView(QWidget *parent=nullptr)
void setMenuProvider(QgsLayerTreeViewMenuProvider *menuProvider)
Set provider for context menu. Takes ownership of the instance.
QgsLayerTreeLayer * findLayer(QgsMapLayer *layer) const
Find layer node representing the map layer.
void expandAllNodes()
Enhancement of QTreeView::expandAll() that also records expanded state in layer tree nodes...
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...
Layer tree node points to a map layer.
static void _expandAllNodes(QgsLayerTreeGroup *parent, bool expanded, QgsLayerTreeModel *model)
QgsLayerTreeNode * currentNode() const
Get current node. May be null.