text_margin.md
In rswipl: Embed 'SWI'-'Prolog'

class text_margin {#class-text_margin}

A text_margin object may be attached to an editor object using the editor ->margin_width method. The margin displays image objects for fragment objects defined on the text_buffer object associated with the editor and thus provides a way for annotating textual information.

Class text_margin is not generally usable; it's functionality is closely related to class editor. The user should not explicitly create instances of this class.

@see class style @see style-icon @see editor->margin_width @see editor-margin @see class fragment

text_margin<-editor: editor Editor I'm part of. Should be the same as <->device.

text_margin->initialise: editor=editor, width=int, height=int Create from editor and dimensions. The user should create and attach a text_margin object using editor ->margin_width.

text_margin<-fragment: event -> fragment Find a fragment (-icon) from an event object. This method may be used to attach event-handling to the icons displayed on the margin. For example, the following recogniser will select a fragment by clicking on the icon:
```
send(Editor?margin, recogniser,
     click_gesture(left, '', single,
                   message(Editor, selected_fragment,
                           ?(@event?receiver, fragment,
                             @event)))).
```