![]() addFeatures () 9 # delete a feature with specified ID 10 layer. setId ( fid ) 6 7 # add two features (QgsFeature instances) 8 layer. Here you have some examples that demonstrate how to use these editing methods.ġ from import QVariant 2 3 feat1 = feat2 = QgsFeature ( layer. To find out whether a layer is in editing mode, use the isEditable() method. One will discard them and will not modify the data source at all. The first one will commit all your changes to the data source, while the second The methods are similar to the ones we have seen in the provider, but they areįor these methods to work, the layer must be in editing mode. When changes are committed, all changes from the editing buffer are Will allow user to decide whether to commit/rollback and allows the usage of This option when providing some GUI tools for vector layer editing, since this Vector layer editing that complements the direct usage of data providers. ![]() This functionality also programmatically - it is just another method for Them - they stay in layer’s in-memory editing buffer. All the changes you make are not written until you commit Mode for a particular layer, then do some modifications and finally commit (or When editing vectors within QGIS application, you have to first start editing Modifying Vector Layers with an Editing Buffer Methods to edit geometries (translate, insert or move vertex, etc.). The QgsVectorLayerEditUtils which provides some useful If you only need to change geometries, you might consider using It contains all the attribute values of this feature 39 print ( attrs ) 40 # for this test only print the first feature 41 breakįavor QgsVectorLayerEditUtils class for geometry-only edits ![]() area ()) 34 else : 35 print ( "Unknown or invalid geometry" ) 36 # fetch attributes 37 attrs = feature. asMultiPolygon () 33 print ( "MultiPolygon: ", x, "Area: ", geom. asPolygon () 30 print ( "Polygon: ", x, "Area: ", geom. PolygonGeometry : 28 if geomSingleType : 29 x = geom. asMultiPolyline () 26 print ( "MultiLine: ", x, "length: ", geom. asPolyline () 23 print ( "Line: ", x, "length: ", geom. LineGeometry : 21 if geomSingleType : 22 x = geom. asMultiPoint () 19 print ( "MultiPoint: ", x ) 20 elif geom. asPoint () 16 print ( "Point: ", x ) 17 else : 18 x = geom. PointGeometry : 13 # the geometry type can be of single or multi type 14 if geomSingleType : 15 x = geom. geometry () 11 geomSingleType = QgsWkbTypes. id ()) 8 # fetch geometry 9 # show some information about the feature geometry 10 geom = feature. getFeatures () 4 5 for feature in features : 6 # retrieve every feature with its geometry and attributes 7 print ( "Feature ID: ", feature. You can retrieve information about the fields associated with a vector layerīy calling fields() on a QgsVectorLayer object:ġ # "layer" is a QgsVectorLayer instance 2 layer = iface. Retrieving information about attributes Most work here is based on the methods of the QgsVectorLayer class. This section summarizes various actions that can be done with vector layers. Modifying Vector Layers with an Editing Buffer Tasks - doing heavy work in the background Expressions, Filtering and Calculating Values QGIS Desktop User Guide/Manual (QGIS 3.28).(princ "\nCan't delete layer in use! ") If vl-catch-all-error-p returns T, then Layer Cannot be Deleted. (list dLay))) If Possible, Delete the Layer ![]() (princ "\nLayer does not exist! ") If vl-catch-all-error-p returns T, then Layer Doesn't Exist (list la圜ol(strcat Name))))) Retrieve Layer Object Name from Layer Collection? (same as tblobjname?) (vlax-get-acad-object)))) Retrieve Current Layer Collection (/= (strcat Name)(getvar "CLAYER")) Check its not Current Layer (defun DeleteLayer(Name / la圜ol dLay oVal) Would you be so kind as to tell me if my annotations are correct, or correct me if I am wrong. I have tried to dissect your code to understand the VL behind it (as I am endeavouring to learn VL now). Many thanks for your code ASMI - there are many error trappings in there to help.
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