AdapTable ships with a number of powerful System Filters which in most cases are sufficient for all needs.
But occasionally you might want to filter a column based on other data in the row or using internal logic not available to the Grid or even using an external lookup.
This is the role of Custom Predicates; they are created at design time and provide 3 imporant pieces of information:
- Column Scope: Which Columns or DataTypes will the Predicate be relevant
- Function Scope: In which Adaptable Functions can the Predicate be called (e.g. Conditional Style, Alerts, Filters etc.)
- Handler: The actual function that will be evaluated each time the predicate is called - it receives node, column and cell details and returns a Boolean
In this example we created 4 Custom Predicates:
- High with Scope of OrderId Column that evaluates based on the data in the Invoiced and ItemCount columns
- New Starter which has Scope of Employee column, and mimics a lookup to an internal CRM system - (this is also set in Config as a column filter)
- Post Takeover which has a Scope of Date columns and evaluates true if date in cell was after a putative takeover date.
- After Work which has Scope of LastUpdatedTime Column and returns any time after 5pm - (this is also set in Config as a column filter )