Fixes:
- enum parameters set to "allow multiple" only allow a single
value selection when used in modeler
- optional enum parameters cannot be set to no value when
used outside of modeler
Fixes#20406
Fixes confusing expression parameter definitions in modeler
child algorithms (there's no direction as to what the
widget should be) and ensures that the correct expression
context is revealed to the widget when in all modes.
This adds a new available parameter type for processing algorithms,
QgsProcessingParameterAuthConfig, allowing selection from available
authentication configurations (and creation of new ones).
It allows creation of processing algorithm which can fully take
advantage of QGIS' mature authentication handling, avoiding the
need to use insecure string parameters for users to input
sensitive logon credentials.
QgsProcessingParameterAuthConfig parameters are evaluated using
QgsProcessingAlgorithm.parameterAsString(), which returns the
selected authentication configuration ID.
Also exposes this capability to modeler - so that model algorithms
can use data defined parameters within their child algorithms.
TODO:
- tests
- setting the associated vector layer
A new widget which handles parameter values for child algorithms
within a model. Instead of the previous approach of requiring
individual widget wrappers to handle creation of a suitable
model widget, we do all this automatically for them.
This widget uses a stacked widget with a toolbutton to select
the parameter's source, instead of the previous combo box approach
(which didn't scale well for large models). I.e. users select
first whether the value is taken from a static value, a
model input, or an output from a different child algorithm. The
widget then changes appearance and behavior based on this
choice.
Additionally, a new option is present for all parameters
of using a "precalculated expression". This expression is
evaluated once before the child algorithm is executed
and used during the execution of that algorithm.
- Add abstract base class for Processing widget wrappers to c++
- Add wrapper factory interface to c++
- Make QgsProcessingGuiRegistry also register widget wrapper
factories, and be responsible for creation of new c++
processing widget wrapper instances
- Start on private c++ implementation of boolean widget wrapper,
including unit tests
