Changing fields name of an attribute table in a layout with PyQGIS 3

Question

I have an attribute table in my layout, defined as follow :

layout = QgsPrintLayout(project)
layout.initializeDefaults()
QgsProject.instance().layoutManager().addLayout(layout)

pdf = QgsProject.instance().mapLayersByName('plan_de_ferme')[0]
pdf_table = QgsLayoutItemAttributeTable.create(layout)
pdf_table.setVectorLayer(pdf)
pdf_fields = ['champ','sup','supepnd']
pdf_table.setDisplayedFields(pdf_fields, True)

I would like to rename the fields name displayed in the layout without changing the fields name in the layer.

I tried :

pdf_headers = ['Champ','Superficie (ha)','Superficie épandable (ha)']
pdf_table.setHeading(pdf_headers)

Like it's the way to do with a QgsLayoutItemTextTable, but it's not working because "AttributeError: 'QgsLayoutItemAttributeTable' object has no attribute 'setHeading'".

Answer 1

You can use the code snippet below:

pdf_headers = ['Champ','Superficie (ha)','Superficie épandable (ha)']

#retrieve layout table columns
cols = pdf_table.columns()

#construct a new list containing cloned QgsLayoutTableColumn objects
new_cols = [col.clone() for col in cols]

#iterate the cloned columns and use setHeading() method to set each
#column's header cell contents to the corresponding item from pdf_headers
for i, cloned_col in enumerate(new_cols):
    cloned_col.setHeading(pdf_headers[i])
    
#set pdf_table columns from the list of cloned and modified
#column objects with new heading contents
pdf_table.setColumns(new_cols)

#refresh layout
layout.refresh()

I tested this code and obtained the following results.

Layout table before:

Layout table after:

While column names in layer remain unchanged:

Answer 2

• Assign pdf_table.columns() to a variable

  columns = pdf_table.columns()
  

• Make changes

  for column, header in zip(columns, pdf_headers):
      column.setHeading(header)
  

• Use setColumns

  pdf_table.setColumns(columns)
  layout.refresh()