Entity selection
When an entity depends on one or more other entities, the entity selection fields enable the user to make this selection. This is especially useful when making a tree-type app.
If none of the below entity selection fields are sufficient, data between entities can be shared using the API.
Select child(ren)
For the selection of a single child entity, the
ChildEntityOptionField
can be used. For example, when the entity
type structure of your application looks similar to the following, and you need your users to select one of the child
entities of a Project
, the following code can be used:
ProjectFolder
└── Project
└── CPTFile
from viktor.parametrization import ViktorParametrization, ChildEntityOptionField
class Parametrization(ViktorParametrization):
selected_cpt = ChildEntityOptionField('Select a CPT')
In case multiple children should be selectable, the
ChildEntityMultiSelectField
can be used.
Select sibling(s)
Similar to children, siblings can be selected using the
SiblingEntityOptionField
:
from viktor.parametrization import ViktorParametrization, SiblingEntityOptionField
class Parametrization(ViktorParametrization):
selected_sibling = SiblingEntityOptionField('Select a sibling')
In case multiple siblings should be selectable, the
SiblingEntityMultiSelectField
can be used.
Select generic entity
In some cases, both the ChildEntityOptionField
and SiblingEntityOptionField
may not be sufficient because the
entities you need to select are in a different part of the entity type tree. In the following example, we want to
select a CPTFile
entity in a Foundation
entity:
ProjectFolder
└── Project
├── CPTFolder
│ └── CPTFile
└── Foundation
We can make use of the EntityOptionField
and the entity_type_names
attribute to filter which entity type(s) should
be selectable:
from viktor.parametrization import ViktorParametrization, EntityOptionField
class FoundationParametrization(ViktorParametrization):
selected_cpt = EntityOptionField('CPT File', entity_type_names=['CPTFile'])
Or use the EntityMultiSelectField
when multiple entities should be selectable:
Entity object
When the user selects an entity with these fields, the entity is returned in the params
as Entity
object.
Please have a look at sharing information between entities for more detail on
how to use an Entity
.
from viktor import ViktorController
from viktor.parametrization import ViktorParametrization, EntityOptionField
class Parametrization(ViktorParametrization):
cpt_entity = EntityOptionField('Select a CPT', entity_type_names=['CPTFile'])
class MyController(ViktorController):
...
@DataView("CPT data", duration_guess=3)
def visualize(self, params, **kwargs):
cpt_entity = params.cpt_entity # Entity | None
if cpt_entity:
return DataResult(DataGroup(
x=DataItem('CPT X coordinate', cpt_entity.last_saved_params.x_coordinate),
y=DataItem('CPT Y coordinate', cpt_entity.last_saved_params.y_coordinate)
))
return DataResult(DataGroup())