Add API method to define placement for new toolbar buttons

[moniuch]

Please consider adding a new method to plugin/widget API to facilitate inserting toolbar buttons at a desired position by specifying an existing 'after' or 'before' member. The goal would be to avoid redefining the global toolbar in the config.

As an exercise I'm writing a simple plugin that allows user to insert a clearfix div. As developer I would expect to be able to easily specify that the button should be sitting next to the Insert Horizontal Line button, without need to redefine the whole toolbar through config.

I'm not sure at this point what kind of fallback should be supported should the target button not be available.

PS. For many reasons I'm close to think that config should be converted from a string into an object.

[moniuch]

A momentary lapse of reason > correction: I didn't mean the config is a string, rather I meant that we should not operate on strings, such as .removeButtons or .extraPlugins. Config should provide methods for such interactions.

[Piotrek Koszuliński]

One plugin shouldn't know about other plugins. Therefore setting 'after', 'before' would be incorrect. What if horizontalrule is not loaded? How would it work then.

That's why CKEditor supports toolbar group + priority setting - e.g. 'insert,10'. If you want to display your button next to horizontal rule, check its position (it's 'insert,40') and specify similar one.