You can add OLE objects and ActiveX controls to a window or user object. To do so, you use one of the PowerBuilder OLE controls, which acts as an OLE container. This section explains how you select the control you want by choosing whether it holds an OLE object (also called an insertable object) or an ActiveX control:
An insertable OLE object is a document associated with a server application. The object can be activated and the server provides commands and toolbars for modifying the object.
An ActiveX control or OLE custom control is itself a server that processes user actions according to scripts you program in PowerBuilder. You can write scripts for ActiveX control events and for events of the PowerBuilder container. Those scripts call functions and set properties that belong to the ActiveX control. When appropriate, the ActiveX control can present its own visual interface for user interaction.
ActiveX controls range from simple visual displays (such as a meter or a gauge) to single activities that are customizable (spellchecking words or phrases) to working environments (image acquisition with annotation and editing).
All OLE control containers support a set of required interfaces. PowerBuilder provides some additional support:
Extended control An OLE control can determine and modify its location at runtime using its extended control properties. PowerBuilder supports the X (Left), Y (Top), Width, and Height properties, all of which are measured in PowerBuilder units. The control writer can access these properties using the IDispatch-based interface returned from the GetExtendedControl method on the IOleControlSite interface.
Window as OLE container PowerBuilder implements the IOleContainer class at the window level, so that all OLE controls on a window are siblings and can obtain information about each other. The control writer can access this information using the OLE EnumObjects method. Information about siblings is useful when the controls are part of a suite of controls. Unlike other controls, the OLE controls on a window are stored in a flat hierarchy.
Message reflection If a control container does not support message reflection, a reflector window is created when an OLE control sends a message to its parent. The reflector window reflects the message back to the control so that the control can process the message itself. If the container supports message reflection, the need for a reflector window, and the associated runtime overhead, is eliminated. PowerBuilder OLE control containers perform message reflection for a specific set of messages.
This procedure describes how to create an OLE control and select its contents.
To place an OLE control in a window or user object:
Open the window or user object that will contain the OLE control.
Select Insert>Control>OLE from the menu bar.
PowerBuilder displays the Insert Object dialog box. There are three tabs to choose from.
Choose a server application or a specific object for the control (which embeds or links an object in the control), select a custom control, or leave the control empty for now:
To create and embed a new object, click the Create New tab. After you have chosen a server application, click OK.
To choose an existing object for the control, click the Create From File tab. After you have specified the file, click OK.
To insert a custom control (ActiveX control), click the Insert Control tab. After you have chosen an ActiveX control, click OK.
To leave the control empty, click Cancel.
If you click Cancel, the control becomes an OLE control rather than an OLE custom control, and you can choose to link or embed an OLE object in it at any time; you cannot insert an ActiveX control later.
Click where you want the control.
If you inserted an object, PowerBuilder opens the server application so you can view and edit the object. ActiveX controls cannot be opened.
If you want to insert an object that belongs to an OLE server application that is not in the list, see the server documentation to find out how to install it.
For more information about using the Insert Object dialog box, see the section on inserting OLE objects in DataWindow objects in the PowerBuilder Users Guide.
