ExpressionPropertyEditor. End-User Capabilities
ExpressionPropertyEditor allows the user to edit formulas created for different types of objects at runtime. The list of expressions is shown in a special List View.
To activate the edit mode, click the Expression Editor Action. The ExpressionPropertyEditor appears in a separate popup window. It has 6 areas, as shown in the figure below.
Let's look at each area one by one:
- This area is intended for output of error messages and debugging results. The respective messages appear after activation of controls Validate or Debug.
- Here is the expression represented by a string of characters. Controls Validate and Debug are located at the right side. The expression editor provides the edit and debug functionality for the entire expression or for the selected part of the expression. Among other things, it checks whether field names are correct. The set of messages on missing fields and syntax error messages was extended.
The expression can refer to a particular business object type. The Type property, which refers to the context type of the business object, is shown in the figure below. The tree of properties of the context business class is displayed in the 3-rd area (when the Fields category is selected). In this case, it is necessary to specify an object in order to debug the expression. Use the 6-th area as shown below, to specify the object.
- These buttons are used to select the operation.
- This area allows to select the required functions, operators, fields, constants, and parameters.
- Functions: It is a set of standard functions complemented by aggregate functions (they can apply to collections). The set of functions can be extended by various custom functions, including the application business operations registered in the project.
- Operators: It shows operators available for the expression.
- Fields: It shows the tree of the context type properties, including collections. Unlike the XtraReport designer, the tree displays both programmed names and localized display names. Properties of aggregated objects are also accessible.
- Constants: Here are the constants defined in the application and available for use in expressions.
- Parameters: Those are named values specified in the application and available for use in expressions. The value of the parameter can change in the course of execution of the application.
- This area shows a description of the element selected in the metadata area (the 4th area). The information is displayed after placing focus on an element.
- This area contains the control that selects the context object in the database. The selected object can be used for debugging the constructed expression. The context type properties are displayed in the 4-th area. The following actions are available:
- Find: open the lookup form.
- Clear: clear the selected value.
- Open current object view : invoke the object's Detail View in the View mode.