QGIS API Documentation  3.21.0-Master (5b68dc587e)
qgsvectorlayerjoininfo.h
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1 /***************************************************************************
2  qgsvectorlayerjoininfo.h
3  ---------------------
4  begin : January 2017
5  copyright : (C) 2017 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 #ifndef QGSVECTORLAYERJOININFO_H
16 #define QGSVECTORLAYERJOININFO_H
17 
18 #include <QHash>
19 #include <QString>
20 #include <QStringList>
21 
22 #include "qgsfeature.h"
23 
24 #include "qgsvectorlayerref.h"
25 
33 class CORE_EXPORT QgsVectorLayerJoinInfo
34 {
35  public:
36 
41 
43  void setJoinLayer( QgsVectorLayer *layer ) { mJoinLayerRef = QgsVectorLayerRef( layer ); }
45  QgsVectorLayer *joinLayer() const { return mJoinLayerRef.get(); }
46 
48  void setJoinLayerId( const QString &layerId ) { mJoinLayerRef = QgsVectorLayerRef( layerId ); }
50  QString joinLayerId() const { return mJoinLayerRef.layerId; }
51 
53  void setTargetFieldName( const QString &fieldName ) { mTargetFieldName = fieldName; }
55  QString targetFieldName() const { return mTargetFieldName; }
56 
58  void setJoinFieldName( const QString &fieldName ) { mJoinFieldName = fieldName; }
60  QString joinFieldName() const { return mJoinFieldName; }
61 
63  void setPrefix( const QString &prefix ) { mPrefix = prefix; }
65  QString prefix() const { return mPrefix; }
66 
68  void setUsingMemoryCache( bool enabled );
69 
74  bool isUsingMemoryCache() const;
75 
81  bool isDynamicFormEnabled() const { return mDynamicForm; }
82 
88  void setDynamicFormEnabled( bool enabled ) { mDynamicForm = enabled; }
89 
95  bool isEditable() const { return mEditable; }
96 
101  void setEditable( bool enabled );
102 
108  bool hasUpsertOnEdit() const { return mUpsertOnEdit; }
109 
115  void setUpsertOnEdit( bool enabled ) { mUpsertOnEdit = enabled; }
116 
122  bool hasCascadedDelete() const { return mCascadedDelete; }
123 
129  void setCascadedDelete( bool enabled ) { mCascadedDelete = enabled; }
130 
137  QString prefixedFieldName( const QgsField &field ) const;
138 
146  QgsFeature extractJoinedFeature( const QgsFeature &feature ) const;
147 
153  Q_DECL_DEPRECATED void setJoinFieldNamesBlackList( const QStringList &blackList ) SIP_DEPRECATED { mBlockList = blackList; }
154 
160  Q_DECL_DEPRECATED QStringList joinFieldNamesBlackList() const SIP_DEPRECATED { return mBlockList; }
161 
168  void setJoinFieldNamesBlockList( const QStringList &list ) { mBlockList = list; }
169 
176  QStringList joinFieldNamesBlockList() const { return mBlockList; }
177 
184  bool hasSubset( bool blocklisted = true ) const;
185 
192  static QStringList joinFieldNamesSubset( const QgsVectorLayerJoinInfo &info, bool blocklisted = true );
193 
194  bool operator==( const QgsVectorLayerJoinInfo &other ) const
195  {
196  return mTargetFieldName == other.mTargetFieldName &&
197  mJoinLayerRef.layerId == other.mJoinLayerRef.layerId &&
198  mJoinFieldName == other.mJoinFieldName &&
199  mJoinFieldsSubset == other.mJoinFieldsSubset &&
200  mMemoryCache == other.mMemoryCache &&
201  mPrefix == other.mPrefix;
202  }
203 
212  void setJoinFieldNamesSubset( QStringList *fieldNamesSubset SIP_TRANSFER ) { mJoinFieldsSubset = std::shared_ptr<QStringList>( fieldNamesSubset ); }
213 
223  QStringList *joinFieldNamesSubset() const { return mJoinFieldsSubset.get(); }
224 
225  protected:
231  QString mJoinFieldName;
232 
237  QString mPrefix;
238 
240  bool mMemoryCache = false;
241 
243  std::shared_ptr<QStringList> mJoinFieldsSubset;
244 
245  // caching support
246 
249 
251  bool cacheDirty = true;
252 
253  bool mDynamicForm = false;
254 
255  bool mEditable = false;
256 
257  bool mUpsertOnEdit = false;
258 
259  bool mCascadedDelete = false;
260 
261  QStringList mBlockList;
262 
264  QHash< QString, QgsAttributes> cachedAttributes;
265 
266 };
267 
268 
269 #endif // QGSVECTORLAYERJOININFO_H
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
Encapsulate a field in an attribute table or data source.
Definition: qgsfield.h:51
Manages joined fields for a vector layer.
Defines left outer join from our vector layer to some other vector layer.
QgsVectorLayerJoinInfo()=default
Constructor for QgsVectorLayerJoinInfo.
void setDynamicFormEnabled(bool enabled)
Sets whether the form has to be dynamically updated with joined fields when a feature is being create...
bool hasCascadedDelete() const
Returns whether a feature deleted on the target layer has to impact the joined layer by deleting the ...
bool operator==(const QgsVectorLayerJoinInfo &other) const
void setJoinLayerId(const QString &layerId)
Sets ID of the joined layer. It will need to be overwritten by setJoinLayer() to a reference to real ...
Q_DECL_DEPRECATED void setJoinFieldNamesBlackList(const QStringList &blackList)
Sets a list of fields to ignore whatever happens.
std::shared_ptr< QStringList > mJoinFieldsSubset
Subset of fields to use from joined layer. nullptr = use all fields.
bool isDynamicFormEnabled() const
Returns whether the form has to be dynamically updated with joined fields when a feature is being cre...
bool hasUpsertOnEdit() const
Returns whether a feature created on the target layer has to impact the joined layer by creating a ne...
bool mMemoryCache
True if the join is cached in virtual memory.
bool isEditable() const
Returns whether joined fields may be edited through the form of the target layer.
QString mPrefix
An optional prefix.
void setCascadedDelete(bool enabled)
Sets whether a feature deleted on the target layer has to impact the joined layer by deleting the cor...
void setJoinFieldName(const QString &fieldName)
Sets name of the field of joined layer that will be used for join.
void setJoinFieldNamesBlockList(const QStringList &list)
Sets a list of fields to ignore whatever happens.
QString mJoinFieldName
Join field in the source layer.
QString prefix() const
Returns prefix of fields from the joined layer. If nullptr, joined layer's name will be used.
void setTargetFieldName(const QString &fieldName)
Sets name of the field of our layer that will be used for join.
QStringList joinFieldNamesBlockList() const
Returns the list of fields to ignore.
QString joinFieldName() const
Returns name of the field of joined layer that will be used for join.
void setUpsertOnEdit(bool enabled)
Sets whether a feature created on the target layer has to impact the joined layer by creating a new f...
QString targetFieldName() const
Returns name of the field of our layer that will be used for join.
QString joinLayerId() const
ID of the joined layer - may be used to resolve reference to the joined layer.
QgsVectorLayer * joinLayer() const
Returns joined layer (may be nullptr if the reference was set by layer ID and not resolved yet)
void setPrefix(const QString &prefix)
Sets prefix of fields from the joined layer. If nullptr, joined layer's name will be used.
QgsVectorLayerRef mJoinLayerRef
Weak reference to the joined layer.
void setJoinLayer(QgsVectorLayer *layer)
Sets weak reference to the joined layer.
Q_DECL_DEPRECATED QStringList joinFieldNamesBlackList() const
Returns the list of fields to ignore.
QStringList * joinFieldNamesSubset() const
Returns the subset of fields to be used from joined layer.
QHash< QString, QgsAttributes > cachedAttributes
Cache for joined attributes to provide fast lookup (size is 0 if no memory caching)
QString mTargetFieldName
Join field in the target layer.
void setJoinFieldNamesSubset(QStringList *fieldNamesSubset)
Sets the subset of fields to be used from joined layer.
Represents a vector layer which manages a vector based data sets.
#define SIP_DEPRECATED
Definition: qgis_sip.h:106
#define SIP_TRANSFER
Definition: qgis_sip.h:36
const QgsField & field
Definition: qgsfield.h:463
_LayerRef< QgsVectorLayer > QgsVectorLayerRef
QString layerId
Original layer ID.