Progress
External Program
Interfaces


Additional Control Functionality

A Progress control container often maintains information regarding the management of the controls it contains. This information is available as an extended control which essentially provides a wrapper around the base control. Even though the extended control maintains the extended properties, methods, and events, each of these appears as though it is part of the base control. As a result, accessing any extended feature is identical to accessing a feature on the base control itself. An example of an extended property is the property Tag, as its functionality is provided by the container. The base control does not even know the property Tag exists. It is the extended control that handles any access to the Tag property.

Properties

Table 9–2 lists the available extended properties.

Table 9–2: Extended Properties 
Property Name
Type
Access
HonorProKeys
logical
read/write at design time
read/write at runtime
Name
string
read/write at design time
read/write at runtime
Parent
COM-handle
read at runtime
Tag
string
read/write at design time
read/write at runtime
Visible
logical
read/write at design time
read/write at runtime

Table 9–3 defines each property and how it can be used.

Table 9–3: Property Definitions
Property
Definition
HonorProKeys
The default value of TRUE allows the Progress code to process the GO, ENDKEY, HELP, or TAB key stroke as each is defined. Setting the value to FALSE causes the control to process the key stroke without Progress code receiving notification that the key stroke occurred.
Name
The Name property contains the name of the control. The name is important because it identifies the control. You can use the control’s name to get a COM-HANDLE to the control
(for example, chCSSpin=chCFSpin:CSSpin, where CSSpin is the control’s name and chCFSpin is the control frame handle). The control name associates event handlers with a control.
Parent
The Parent property is the com-handle (a pointer to the IDispatch interface) of the container in which the control resides. This property is set internally by Progress.
Tag
The Tag property is a user property that allows the user to store an arbitrary string value and retrieve it later. Progress does not use this property internally, and it is intended to give the user a way of storing application specific information with the control. This property is initialized to an empty string.
Visible
The Visible property determines and indicates whether an ActiveX control is currently displayed. The Visible property is distinct from, but influenced by, the Visible and Hidden attributes of the Control-Frame widget. The Visible property will appear in the Property Editor and can be set at design time. It defaults to TRUE. The value set in the Property Editor determines whether the OCX is initially displayed when the program is run, but can be overriden by the value of the Control-Frame widget’s Hidden attribute.
Some ActiveX controls are never displayed at runtime (for example, a timer control.) For these controls, the Visible property will not appear in the Property Editor and attempts to set the property at runtime will have no effect.


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