Integration Action Plan

This section suggests a plan of action for integrating your application with drag and drop in Common Desktop Environment 1.3.

Review Drag-and-Drop API and Sample Code

Use the information provided in this chapter to familiarize yourself with the drag-and-drop API. Once you have a basic understanding of the API, review the source code for the drag-and-drop demo program, /usr/dt/examples/dtdnd. This code provides examples of how to use the API in various ways. The examples should give you an understanding of the character and amount of code you need to write to support drag and drop in your application. Understanding the actions and the data-typing API is useful as well.

Review Your Application for Possible Drop Zones

Identify the types of data your application might accept through a drag-and-drop transaction. If, for example, you are writing a bitmap editor, you want to support the drop of files. Once you have identified the data types you will allow to be dropped on your application, determine the widget or widgets that should be drop zones. For the bitmap editor example, you may decide the only place a file should be dropped on the application is the bitmap editing area. In this case, register the widget representing this area using DtDndDropRegister() and provide the appropriate callbacks.

Because it is easiest to handle the drop of file names, start by implementing them. Once you have mastered this technique, you will find it easier to move on to implementing the drop of text and buffers.

Review Your Application for Possible Drag Sources

Identify the types of data your application might permit as sources for a drag-and-drop transaction. In the example of the bitmap editor, you may want bitmap data containing the current bitmap selection to be a drag source as an accelerator for cut and paste. Once you have identified the data types you will allow to be dragged from your application, determine the widget or widgets that should be drag sources. In the bitmap editor example, you may decide the bitmap editing area containing the highlighted bitmap selection should serve as the drag source. In this case, enable the widget representing this area for sourcing drags.

Start by implementing the drag of buffers that are most appropriate or specific to your application. You will also want to add the ability to drop buffers on your application to enable easy data transfer between multiple invocations of your application.