Class: DataBindingCommandHandler

Inherits:
Object
  • Object
show all
Extended by:
Glimmer
Includes:
CommandHandler
Defined in:
lib/command_handlers/data_binding_command_handler.rb

Overview

Responsible for wiring two-way data-binding for text and selection properties on Text, Button, and Spinner widgets. Does so by using the output of the bind(model, property) command in the form of a ModelBinding, which is then connected to an anonymous widget observer (aka widget_data_binder as per widget_data_binders array)

Depends on BindCommandHandler

Constant Summary collapse

@@widget_data_binders = 
{
Java::OrgEclipseSwtWidgets::Text => {
  :text => Proc.new do |rwidget, model_binding|
    add_contents(rwidget) {
      on_modify_text { |modify_event|
        model_binding.update(rwidget.widget.getText)
      }
    }
    end,
  },
  Java::OrgEclipseSwtWidgets::Button => {
    :selection => Proc.new do |rwidget, model_binding|
      add_contents(rwidget) {
        on_widget_selected { |selection_event|
          model_binding.update(rwidget.widget.getSelection)
        }
      }
    end
  },
  Java::OrgEclipseSwtWidgets::Spinner => {
    :selection => Proc.new do |rwidget, model_binding|
      add_contents(rwidget) {
        on_widget_selected { |selection_event|
          model_binding.update(rwidget.widget.getSelection)
        }
      }
    end
  }
}

Instance Method Summary collapse

Methods included from Glimmer

add_contents, add_contents, dsl, dsl, extended, included, logger, method_missing, method_missing

Methods included from SwtPackages

included

Instance Method Details

#can_handle?(parent, command_symbol, *args, &block) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/command_handlers/data_binding_command_handler.rb', line 50

def can_handle?(parent, command_symbol, *args, &block)
  (parent.is_a?(RWidget) and
   args.size == 1 and
   args[0].is_a?(ModelBinding))
end

#do_handle(parent, command_symbol, *args, &block) ⇒ Object 



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# File 'lib/command_handlers/data_binding_command_handler.rb', line 56

def do_handle(parent, command_symbol, *args, &block)
  model_binding = args[0]
  widget_binding_parameters = [parent, command_symbol.to_s]
  widget_binding = WidgetBinding.new(*widget_binding_parameters)
  widget_binding.update(model_binding.evaluate_property)
  widget_binding.observe(model_binding)
  widget_data_binder_map = @@widget_data_binders[parent.widget.class]
  widget_data_binder = widget_data_binder_map[command_symbol.to_s.to_sym] if widget_data_binder_map
  widget_data_binder.call(parent, model_binding) if widget_data_binder
end