With an onget method member you can implement the logic to execute when the corresponding property is evaluated within an expression. This allows you to handle every read access to the property. The onget methods are represented in Composer by following bricks:

The onget method should determine or calculate the value of the property and return it. Every onget method has a body containing its implementation code. The code is expressed in the platform-independent Chora syntax. Within the code you can evaluate and modify variables, perform calculations, call other methods, etc.

An onget method can be defined within a class or class variant only. Moreover, the class must contain a property corresponding to the onget method. Stand-alone onget methods are not possible. If one class is derived from another class, all methods implemented in the ancestor classes are inherited implicitly. In the derived class the inherited methods can be overridden and modified with new implementation.

In order to preserve the clarity, all methods inherited from a base class but not overridden in the actual class are not shown as bricks in the Composer. The Inspector, in turn, shows always the complete list including all inherited members. If you are looking for a particular inherited method, use the Inspector for this purpose. Please note, inherited but not overridden methods are shown in Inspector with gray thin font:

Inherited but not overridden onget methods appear only in the Inspector window. They are shown with thin gray font.

If an inherited method has been overridden, Inspector shows it with dark gray font. Additionally, overridden methods appear as bricks in the Composer window. You can distinguish easily, whether a method is overridden or whether it is new by considering the font color in its brick. New methods are shown with black font. Overridden methods, in turn, with gray font:

Overridden methods appear in Inspector with dark gray font. They are also shown as bricks in Composer, again with gray font.

Adding a new onget method.

Please note, new added properties contain per default already an onget and onset method.

The onget methods are named consistently after their corresponding properties extended only by an additional OnGet prefix. For example, the property TextColor is associated with the onget method OnGetTextColor. Please note, the name of an inherited onget method can't be changed retrospectively in the derived class.

The body of an onget method is edited in the Code Editor window. For this purpose:

In the Code Editor you implement the method by using Chora statements and expressions.

Please note, before you can edit an inherited method, you have to override it first.

It is explicitly required, that an onget method returns a value. The data type of the value must match the declaration of the corresponding property. To return a value you use in the implementation of the onget method the return statement.

Every property has its own associated internal memory, where the current value of the property can be stored, similar to how values are stored in variables. The onget method may evaluate this internal memory, calculate with it and return its content. The memory is accessed by prefixing the property name by the keyword pure. Let's assume, you have a property Size declared with point as its data type, then its onget method could be implemented as follows:

You can create any number of copies of an already existing onget method.

When you duplicate the onget method, you should also duplicate its associated property. Stand-alone onget methods are not permitted.

In order to provide new implementation for an inherited method, you have to override it explicitly:

Overriding an inherited onget method.

When you override an inherited method, it is often convenient to invoke from the new implementation the inherited version of the method. This can be achieved by calling the pseudo method super(). Let's assume, you have a property named Size declared with point as its data type, then its onget method could be implemented as follows:

If you want to revert an overridden onget method to its original inherited implementation, delete it simply. Thereupon, its brick disappears from the Composer and the Inspector shows the method name with thin font again.

The onget method is invoked implicitly when the corresponding property is evaluated within an expression. Invoking the method directly is not possible.

With the attribute Generator you can selectively control, whether the method should be taken in account during the code generation or not. Configuring this attribute with the value false will exclude the method from your project unless the corresponding property is explicitly evaluated within a Chora expression.

Please note, inherited methods can't be deleted. However, if a method is overridden you can delete this overriding.

The following table shows the complete list of attributes provided by the onget method member:

Attribute name	Short description
Brick	Determines the position and the size of an onget method brick within the Composer window.
Description	Contains the description for the onget method member.
Generator	Controls the code generation for the affected onget method member.
Native	Specifies the kind of language the corresponding method is implemented in.

This section describes the Chora syntax of how OnGet methods are stored inside Embedded Wizard project files. The knowledge about the syntax can be helpful when you plan to process the project contents by third party tools. In particular, the general purpose Export and Import functionality introduced in version 14 requires a good understanding of how project members are represented in Chora syntax to correctly interpret the exported members and synthesize the Chora code for members to import. Please note, Embedded Wizard project files (and thus Chora code) are encoded as text in UTF-8 format.

In Chora syntax, OnGet method definition is always introduced with the keyword onget, followed by the name and the body (the implementation) of the method. The body of the method is enclosed between a pair of curly braces {..}. In the implementation of the method the Chora statements are used. Wherever necessary, the tokens are separated by whitespace signs.

The definition of a method can be initiated by a comment block providing optional description for the method. The content of this comment corresponds to the value of the methods's attribute Description. Furthermore the directives $rect and $output can be specified providing values for the corresponding attributes Brick and Generator.

In case of a method inherited from a base class, the method definition is additionally prefixed by the keyword inherited. In this case the method inherits the value for the $output directive from the base class. Modifying this value in the inherited method is not foreseen. The following examples demonstrate the described syntax:

Each Chora file (or text exchanged with an external Export and/or Import tool) can be (or even should be) prefixed with $version directive. This directive determines the version number of the included Chora code. For details concerning the syntax of the version please see the chapter $version macro. Furthermore, the code can include a $scope directive followed by a path to a project member acting as the original owner of the corresponding code. That means the members described by the Chora code existed inside the member specified in $scope. In case of a method, $scope would specify the name of the class the method belongs to.