Release 10.1A: OpenEdge Getting Started:
Progress OpenEdge Studio

Drag and Drop module

The Progress 4GL can read the names of files that an end user drops onto certain widgets. With this functionality, the end user can populate widgets, like selection lists, with a list of files. The Progress 4GL can also use the filenames to retrieve the files and open them in appropriate widgets. Using these techniques, you could save your users time by allowing them to load data into your program by dragging a filename from the Windows Explorer or Desktop onto a widget in your application.

To launch this module, choose the Drag and Drop button on the SportsPro main window. The Drag and Drop dialog box appears:

Implementing this technique is simple. You set the DROP–TARGET attribute on the property sheet of a selection list or editor widget and code the trigger event. For images, the DROP–TARGET attribute is set on the frame that holds the image. When a file is dropped on an object with the DROP-TARGET attribute enabled, the DROP–FILE–NOTIFY event fires.

Note: If you cannot click on an object, it is probably behind another object in the window’s layout. Use the Layout menu to move the top object back, or use the List Objects dialog box to access the bottom object.

Table 2–5 describes the major objects used in the Drag and Drop module.

Table 2–5: Components of the Drag and Drop module 

Object or filename	Object type	Function
wdragdrop.w	SmartWindow	Serves as a container for the other objects in the module.
fMain	SmartFrame	Acts as the drop-target for image files. It reads the filename and then displays the image.
SELECT–1	Selection-list	Acts as the drop-target for filenames. It reads the filenames and then adds them to the list of selections.
EDITOR–1	Editor	Acts as the drop-target for text files. It reads the filename and then opens the file in the editor.

For more information on how drag and drop works, see the entries for the DROP–TARGET attribute, the END–FILE–DROP( ) method, the GET–DROPPED–FILE( ) method, the DROP–FILE–NOTIFY event, and the NUM–DROPPED–FILES attribute in the OpenEdge Development: Progress 4GL Reference .