Add relation widget registry

python/core/auto_generated/qgsattributeeditorelement.sip.in

@@ -113,6 +113,20 @@ Controls if this element should be labeled with a title (field, relation or grou
 Controls if this element should be labeled with a title (field, relation or groupname).
 
 .. versionadded:: 2.18
+%End
+
+    QVariantMap config() const;
+%Docstring
+Returns the editor configuration
+
+.. versionadded:: 3.18
+%End
+
+    void setConfig( const QVariantMap &config );
+%Docstring
+Sets the editor configuration
+
+.. versionadded:: 3.18
 %End
 
   protected:
@@ -411,18 +425,24 @@ Determines if the "Save child layer edits" button should be shown
    use visibleButtons() instead
 %End
 
-    void setVisibleButtons( const QgsAttributeEditorRelation::Buttons &buttons );
+ void setVisibleButtons( const QgsAttributeEditorRelation::Buttons &buttons );
 %Docstring
 Defines the buttons which are shown
 
 .. versionadded:: 3.16
+
+.. deprecated:: QGIS 3.18
+   use setConfig() instead
 %End
 
-    QgsAttributeEditorRelation::Buttons visibleButtons() const;
+ QgsAttributeEditorRelation::Buttons visibleButtons() const;
 %Docstring
 Returns the buttons which are shown
 
 .. versionadded:: 3.16
+
+.. deprecated:: QGIS 3.18
+   use setConfig() instead
 %End
 
     bool forceSuppressFormPopup() const;
@@ -469,6 +489,16 @@ Sets ``label`` for this element
 If it's empty it takes the relation id as label
 
 .. versionadded:: 3.16
+%End
+
+    QString relationWidgetTypeId() const;
+%Docstring
+Returns the current relation widget type id
+%End
+
+    void setRelationWidgetTypeId( const QString &relationWidgetTypeId );
+%Docstring
+Sets the relation widget type
 %End
 
 };

python/gui/auto_additions/qgsbasicrelationwidget.py

@@ -0,0 +1,4 @@
+# The following has been generated automatically from src/gui/qgsbasicrelationwidget.h
+QgsBasicRelationWidget.Button.baseClass = QgsBasicRelationWidget
+QgsBasicRelationWidget.Buttons.baseClass = QgsBasicRelationWidget
+Buttons = QgsBasicRelationWidget  # dirty hack since SIP seems to introduce the flags in module

python/gui/auto_generated/editorwidgets/qgsrelationwidgetwrapper.sip.in

@@ -18,7 +18,23 @@ class QgsRelationWidgetWrapper : QgsWidgetWrapper
 %End
   public:
 
-    explicit QgsRelationWidgetWrapper( QgsVectorLayer *vl, const QgsRelation &relation, QWidget *editor = 0, QWidget *parent /TransferThis/ = 0 );
+    QgsRelationWidgetWrapper(
+      QgsVectorLayer *vl,
+      const QgsRelation &relation,
+      QWidget *editor /Constrained/ = 0,
+      QWidget *parent /TransferThis,Constrained/  = 0
+    );
+%Docstring
+Constructor for QgsRelationWidgetWrapper
+%End
+
+    QgsRelationWidgetWrapper(
+      const QString &relationEditorName,
+      QgsVectorLayer *vl,
+      const QgsRelation &relation,
+      QWidget *editor = 0,
+      QWidget *parent /TransferThis/ = 0
+    );
 %Docstring
 Constructor for QgsRelationWidgetWrapper
 %End
@@ -99,18 +115,35 @@ Determines if the "Save child layer edits" button should be shown
    use visibleButtons() instead
 %End
 
-    void setVisibleButtons( const QgsAttributeEditorRelation::Buttons &buttons );
+ void setVisibleButtons( const QgsAttributeEditorRelation::Buttons &buttons );
 %Docstring
 Defines the buttons which are shown
 
 .. versionadded:: 3.16
+
+.. deprecated:: QGIS 3.18
 %End
 
-    QgsAttributeEditorRelation::Buttons visibleButtons() const;
+ QgsAttributeEditorRelation::Buttons visibleButtons() const;
 %Docstring
 Returns the buttons which are shown
 
 .. versionadded:: 3.16
+
+.. deprecated:: QGIS 3.18
+%End
+
+
+    void setWidgetConfig( const QVariantMap &config );
+%Docstring
+Will set the config of this widget wrapper to the specified config.
+
+:param config: The config for this wrapper
+%End
+
+    QVariantMap widgetConfig() const;
+%Docstring
+Returns the whole widget config
 %End
 
     bool forceSuppressFormPopup() const;

python/gui/auto_generated/qgsbasicrelationwidget.sip.in

@@ -0,0 +1,110 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/qgsbasicrelationwidget.h                                     *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+
+
+
+class QgsBasicRelationWidget : QgsRelationWidget
+{
+%Docstring
+The default relation widget in QGIS. Successor of the now deprecated {:py:class:`QgsRelationEditorWidget`}.
+
+.. versionadded:: 3.18
+%End
+
+%TypeHeaderCode
+#include "qgsbasicrelationwidget.h"
+%End
+  public:
+
+    enum Button
+    {
+      Link,
+      Unlink,
+      SaveChildEdits,
+      AddChildFeature,
+      DuplicateChildFeature,
+      DeleteChildFeature,
+      ZoomToChildFeature,
+      AllButtons
+    };
+    typedef QFlags<QgsBasicRelationWidget::Button> Buttons;
+
+
+    QgsBasicRelationWidget( const QVariantMap &config, QWidget *parent /TransferThis/ = 0 );
+%Docstring
+Constructor
+
+:param config: widget configuration
+:param parent: parent widget
+%End
+
+    void setViewMode( QgsDualView::ViewMode mode );
+%Docstring
+Define the view mode for the dual view
+%End
+
+    QgsDualView::ViewMode viewMode();
+%Docstring
+Gets the view mode for the dual view
+%End
+
+    void setEditorContext( const QgsAttributeEditorContext &context );
+%Docstring
+Sets the editor ``context``
+
+.. note::
+
+   if context cadDockWidget is null, it won't be possible to digitize
+   the geometry of a referencing feature from this widget
+%End
+
+    void setVisibleButtons( const Buttons &buttons );
+%Docstring
+Defines the buttons which are shown
+%End
+
+    Buttons visibleButtons() const;
+%Docstring
+Returns the buttons which are shown
+%End
+
+    virtual QVariantMap config() const;
+
+%Docstring
+Returns the current configuration
+%End
+
+    virtual void setConfig( const QVariantMap &config );
+
+%Docstring
+Defines the current configuration
+%End
+
+    virtual void setTitle( const QString &title );
+
+%Docstring
+Sets the title of the root groupbox
+%End
+
+  public slots:
+    virtual void parentFormValueChanged( const QString &attribute, const QVariant &newValue );
+
+
+};
+
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/qgsbasicrelationwidget.h                                     *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/

python/gui/auto_generated/qgsgui.sip.in

@@ -129,6 +129,13 @@ Returns the registry of subset string editors of data providers
 %Docstring
 Returns the registry of provider source widget providers.
 
+.. versionadded:: 3.18
+%End
+
+    static QgsRelationWidgetRegistry *relationWidgetRegistry() /KeepReference/;
+%Docstring
+Returns the global relation widget registry, used for managing all known relation widget factories.
+
 .. versionadded:: 3.18
 %End
 

python/gui/auto_generated/qgsrelationconfigwidget.sip.in

@@ -0,0 +1,77 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/qgsrelationconfigwidget.h                                    *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+
+
+
+
+class QgsRelationConfigWidget : QWidget
+{
+%Docstring
+This class should be subclassed for every configurable relation widget type.
+
+It implements the GUI configuration widget and transforms this to/from a configuration.
+
+It will only be instantiated by {:py:class:`QgsRelationWidgetFactory`}
+
+.. versionadded:: 3.18
+%End
+
+%TypeHeaderCode
+#include "qgsrelationconfigwidget.h"
+%End
+  public:
+
+    explicit QgsRelationConfigWidget( const QgsRelation &relation, QWidget *parent /TransferThis/ );
+%Docstring
+Create a new configuration widget
+
+:param relation: The relation for which the configuration dialog will be created
+:param parent: A parent widget
+%End
+
+    virtual QVariantMap config() = 0;
+%Docstring
+Create a configuration from the current GUI state
+
+:return: A widget configuration
+%End
+
+    virtual void setConfig( const QVariantMap &config ) = 0;
+%Docstring
+Update the configuration widget to represent the given configuration.
+
+:param config: The configuration which should be represented by this widget
+%End
+
+    QgsVectorLayer *layer();
+%Docstring
+Returns the layer for which this configuration widget applies
+
+:return: The layer
+%End
+
+    QgsRelation relation() const;
+%Docstring
+Returns the relation for which this configuration widget applies
+
+:return: The relation
+%End
+
+
+};
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/qgsrelationconfigwidget.h                                    *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/