[Eclipse] GEF Introduction Series (preface)

Due to the needs of the work, recently began to study the GEF (graphical Editor framework), which can be used to provide users with a graphical editing model to enhance the user experience, typical applications such as the graphical process designer, UML class diagram editor, and so on. In fact, for more than a year we have to do the project is related to it, but before I specifically responsible for the matter and it has no relationship. At that time also saw the yellow Old capital Code, EMF and GEF mixed together particularly dizzy, did not stick to see. This time I have to do it, just take the opportunity to understand it, feel that the things GEF do give people a very professional feeling, the function is also very strong, should be quite promising. In addition, GEF uses a lot of Classic mode, the most prominent such as a large number of application command mode, convenient implementation of Undo/redo functions, etc., by learning GEF, is equivalent to the practice of these patterns, than just to see how to write a few classes that way of learning the effect of a lot better.

Now the Internet on GEF articles and tutorials are not many (compared to a year ago or added a few), basically are eclipse.org on those, and a few of them have Chinese version, the original Chinese is rare, the market does not seem to have this book. Documents that are brought in the GEF SDK are more abstract and unsuitable for getting started. I think the best way to get started is to combine concrete examples, look at the code, control the document, and then do it yourself. Of course, this is a simple example to be good, like GEF's logic example is too complicated, even if the flow (see the diagram below) I feel a bit large; another example to be more normative, otherwise the study of the wrong way to spend time to change it is not worthwhile.

The process editor written with GEF

GEF's architecture determines the complexity of GEF applications, and even the simplest GEF program contains five or six packages and more than 10 classes, and it's normal to get dizzy when it comes to getting started. I found a good example, and of course it was simple, if you want to try it now. GEF, you can click here to download a Zip package (if you are unable to download please use this link), launched after six items (Pt1,pt2,..., pt6), each is based on the previous one to add some features to get, PT1 is the simplest one so you can see how the typical features (such as directedit, palette, etc.) should be implemented in GEF. For more information on this example, see the author's blog note: