[news.eclipse.tools.gef] Re: Dispatching Event from Figure to EditPart

[Pascal Gelinas <pascal.gelinas@xxxxxxxxxx>]

ngotme@xxxxxx wrote:
> Hello all,
>
> I want to react on a click on a label in a figure and pass it to the 
> corresponding editpart in order to create a request and change the model.
> What is the best practice to do so? How would I dispatch the mouseClick 
> event to the editpart?
> Thanks in advance

I'm guessing you want some custom behavior on a single click of the 
figure, so I'll start from there. First of all, you need to have a 
selection tool entry in your palette. You need to modify the tool it 
gives you for your own SelectionTool. The default one does not ask the 
edit part for a command, and that's what we want here. So, subclass 
SelectionTool, and extend the #mouseDown() method as follow:
        @Override
        public void mouseDown(MouseEvent e, EditPartViewer viewer)
        {
            // Let the superclass treat it before you, so its state 
updates.
            super.mouseDown(e, viewer);
            Command command = getCommand();
            getCommandStack().execute(command);
        }
note: you may which to extend something else, such has 
#handleButtonUp(), or #mouseUp(). The #mouseDown() approach was only for 
 quick testing. Also, I didn't do any error checking which you may or 
may not need.

Then, you need to tell the selection tool entry which tool to use. There 
is two way for that:
1- pass your own class to the #setToolClass() method (I had no luck with 
this tho)
2- subclass SelectionToolEntry and override #createTool as follow:
            @Override
            public Tool createTool()
            {
                Tool tool = new Test();
                tool.setProperties(getToolProperties());
                return tool;
            }

Then, all you need is an edit policy on your edit part which understand 
the REQ_SELECTION and gives you the command.

Hope this helps.
--
Pascal GÃlinas | Software Developer
*Nu Echo Inc.*
http://www.nuecho.com/ | http://blog.nuecho.com/

*Because performance matters.*