Class: Glimmer::SWT::WidgetProxy

Inherits:
Object
  • Object
show all
Includes:
Glimmer, PropertyOwner
Defined in:
lib/glimmer/swt/widget_proxy.rb

Constant Summary collapse

DEFAULT_INITIALIZERS = 
{
  "composite" => lambda do |composite_proxy|
    if composite_proxy.layout.nil?
      layout = GridLayoutProxy.new(composite_proxy, [])
      composite_proxy.layout = layout
      layout.margin_width = 15
      layout.margin_height = 15
    end
  end,
#         "scrolled_composite" => lambda do |scrolled_composite|
#           scrolled_composite.expand_horizontal = true
#           scrolled_composite.expand_vertical = true
#         end,
#         "table" => lambda do |table|
#           table.setHeaderVisible(true)
#           table.setLinesVisible(true)
#         end,
  "table_column" => lambda do |table_column_proxy|
    table_column_proxy.width = 80
  end,
#         "group" => lambda do |group_proxy|
#           group_proxy.layout = GridLayoutProxy.new(group_proxy, []) if group.layout.nil?
#         end,
}

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from PropertyOwner

#attribute_getter, #attribute_setter, #get_attribute

Constructor Details

#initialize(parent, args, block) ⇒ WidgetProxy

Returns a new instance of WidgetProxy.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 103

def initialize(parent, args, block)
  @parent = parent
  @args = args
  @block = block
  @children = Set.new # TODO consider moving to composite
  @enabled = true
  @data = {}
  DEFAULT_INITIALIZERS[self.class.underscored_widget_name(self)]&.call(self)
  @parent.post_initialize_child(self) # TODO rename to post_initialize_child to be closer to glimmer-dsl-swt terminology
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method, *args, &block) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 411

def method_missing(method, *args, &block)
  if method.to_s.start_with?('on_')
    handle_observation_request(method, &block)
  else
    super(method, *args, &block)
  end
end

Instance Attribute Details

#args ⇒ Object (readonly)

Returns the value of attribute args.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def args
  @args
end

#background ⇒ Object

Returns the value of attribute background.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def background
  @background
end

#children ⇒ Object (readonly)

Returns the value of attribute children.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def children
  @children
end

#disposed? ⇒ Object (readonly) Also known as: isDisposed, is_disposed

Returns the value of attribute disposed?.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def disposed?
  @disposed?
end

#enabled ⇒ Object

Returns the value of attribute enabled.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def enabled
  @enabled
end

#focus ⇒ Object

Returns the value of attribute focus.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def focus
  @focus
end

#font ⇒ Object

Returns the value of attribute font.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def font
  @font
end

#foreground ⇒ Object

Returns the value of attribute foreground.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def foreground
  @foreground
end

#parent ⇒ Object (readonly)

Returns the value of attribute parent.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def parent
  @parent
end

#path ⇒ Object (readonly)

Returns the value of attribute path.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def path
  @path
end

#rendered ⇒ Object (readonly) Also known as: rendered?

Returns the value of attribute rendered.



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# File 'lib/glimmer/swt/widget_proxy.rb', line 32

def rendered
  @rendered
end

Class Method Details

.for(keyword, parent, args, block) ⇒ Object

Factory Method that translates a Glimmer DSL keyword into a WidgetProxy object



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# File 'lib/glimmer/swt/widget_proxy.rb', line 39

def for(keyword, parent, args, block)
  the_widget_class = widget_class(keyword)
  the_widget_class.respond_to?(:create) ? the_widget_class.create(keyword, parent, args, block) : the_widget_class.new(parent, args, block)
end

.max_id_number_for(name) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 61

def max_id_number_for(name)
  @max_id_numbers[name] = max_id_numbers[name] || 0
end

.max_id_numbers ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 65

def max_id_numbers
  @max_id_numbers ||= reset_max_id_numbers!
end

.next_id_number_for(name) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 57

def next_id_number_for(name)
  @max_id_numbers[name] = max_id_number_for(name) + 1
end

.reset_max_id_numbers! ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 69

def reset_max_id_numbers!
  @max_id_numbers = {}
end

.underscored_widget_name(widget_proxy) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 73

def underscored_widget_name(widget_proxy)
  widget_proxy.class.name.split(/::|\./).last.sub(/Proxy$/, '').underscore
end

.widget_class(keyword) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 44

def widget_class(keyword)
  class_name_alternative = keyword.camelcase(:upper)
  class_name_main = "#{class_name_alternative}Proxy"
  Glimmer::SWT.const_get(class_name_main.to_sym) rescue Glimmer::SWT.const_get(class_name_alternative.to_sym)
rescue => e
  puts "Widget #{keyword} was not found!"
  nil
end

.widget_exists?(keyword) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/glimmer/swt/widget_proxy.rb', line 53

def widget_exists?(keyword)
  !!widget_class(keyword)
end

Instance Method Details

#add_content_on_render(&content_block) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 246

def add_content_on_render(&content_block)
  if rendered?
    content_block.call
  else
    content_on_render_blocks << content_block
  end
end

#add_css_class(css_class) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 304

def add_css_class(css_class)
  dom_element.add_class(css_class)
end

#add_css_classes(css_classes_to_add) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 308

def add_css_classes(css_classes_to_add)
  css_classes_to_add.each {|css_class| add_css_class(css_class)}
end

#add_observer(observer, property_name) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 398

def add_observer(observer, property_name)
  property_listener_installers = self.class&.ancestors&.to_a.map {|ancestor| widget_property_listener_installers[ancestor]}.compact
  widget_listener_installers = property_listener_installers.map{|installer| installer[property_name.to_s.to_sym]}.compact if !property_listener_installers.empty?
  widget_listener_installers.to_a.each do |widget_listener_installer|
    widget_listener_installer.call(observer)
  end
end

#apply_property_type_converters(attribute_name, args) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 419

def apply_property_type_converters(attribute_name, args)
  if args.count == 1
    value = args.first
    converter = property_type_converters[attribute_name.to_sym]
    args[0] = converter.call(value) if converter
  end
#         if args.count == 1 && args.first.is_a?(ColorProxy)
#           g_color = args.first
#           args[0] = g_color.swt_color
#         end
end

#build_dom(layout = true) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 254

def build_dom(layout=true)
  # TODO consider passing parent element instead and having table item include a table cell widget only for opal
  @dom = nil
  @dom = dom
  @dom = @parent.layout.dom(@dom) if @parent.respond_to?(:layout) && @parent.layout
  @dom
end

#can_handle_observation_request?(observation_request) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/glimmer/swt/widget_proxy.rb', line 357

def can_handle_observation_request?(observation_request)
  # TODO sort this out for Opal
  observation_request = observation_request.to_s
  if observation_request.start_with?('on_swt_')
    constant_name = observation_request.sub(/^on_swt_/, '')
    SWTProxy.has_constant?(constant_name)
  elsif observation_request.start_with?('on_')
#           event = observation_request.sub(/^on_/, '')
#           can_add_listener?(event) || can_handle_drag_observation_request?(observation_request) || can_handle_drop_observation_request?(observation_request)
    true # TODO filter by valid listeners only in the future
  end
end

#clear_css_classes ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 320

def clear_css_classes
  css_classes.each {|css_class| remove_css_class(css_class)}
end

#content(&block) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 262

def content(&block)
  Glimmer::DSL::Engine.add_content(self, Glimmer::DSL::Opal::WidgetExpression.new, &block)
end

#content_on_render_blocks ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 242

def content_on_render_blocks
  @content_on_render_blocks ||= []
end

#css_classes ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 142

def css_classes
  dom_element.attr('class').to_s.split
end

#default_observation_request_to_event_mapping ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 275

def default_observation_request_to_event_mapping
  {
    'on_focus_gained' => {
      event: 'focus',
    },
    'on_focus_lost' => {
      event: 'blur',
    },
  }
end

#dispose ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 146

def dispose
  remove_all_listeners
  Document.find(path).remove
  parent&.post_dispose_child(self)
  # TODO fire on_widget_disposed listener
  @disposed = true
end

#dom_element ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 328

def dom_element
  # TODO consider making this pick an element in relation to its parent, allowing unhooked dom elements to be built if needed (unhooked to the visible page dom)
  Document.find(path)
end

#effective_observation_request_to_event_mapping ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 271

def effective_observation_request_to_event_mapping
  default_observation_request_to_event_mapping.merge(observation_request_to_event_mapping)
end

#element ⇒ Object

Root element representing widget. Must be overridden by subclasses if different from div



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# File 'lib/glimmer/swt/widget_proxy.rb', line 173

def element
  'div'
end

#get_data(key = nil) ⇒ Object Also known as: getData, data 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 136

def get_data(key=nil)
  @data[key]
end

#handle_observation_request(keyword, &event_listener) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 374

def handle_observation_request(keyword, &event_listener)
  return unless effective_observation_request_to_event_mapping.keys.include?(keyword)
  event = nil
  delegate = nil
  effective_observation_request_to_event_mapping[keyword].to_collection.each do |mapping|
    observation_requests[keyword] ||= Set.new
    observation_requests[keyword] << event_listener
    event = mapping[:event]
    event_handler = mapping[:event_handler]
    event_element_css_selector = mapping[:event_element_css_selector]
    potential_event_listener = event_handler&.call(event_listener)
    event_listener = potential_event_listener || event_listener
    async_event_listener = lambda do |event|
      Async::Task.new do
        event_listener.call(event)
      end
    end
    the_listener_dom_element = event_element_css_selector ? Element[event_element_css_selector] : listener_dom_element
    delegate = the_listener_dom_element.on(event, &async_event_listener)
  end
  # TODO update code below for new WidgetProxy API
  EventListenerProxy.new(element_proxy: self, event: event, selector: selector, delegate: delegate)
end

#has_style?(symbol) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/glimmer/swt/widget_proxy.rb', line 324

def has_style?(symbol)
  @args.include?(symbol) # not a very solid implementation. Bring SWT constants eventually
end

#id ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 290

def id
  @id ||= "#{name}-#{WidgetProxy.next_id_number_for(name)}"
end

#id=(value) ⇒ Object

Sets id explicitly. Useful in cases of wanting to maintain a stable id



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# File 'lib/glimmer/swt/widget_proxy.rb', line 295

def id=(value)
  @id = value
end

#listener_dom_element ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 353

def listener_dom_element
  Document.find(listener_path)
end

#listener_path ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 349

def listener_path
  path
end

#name ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 286

def name
  self.class.name.split('::').last.underscore.sub(/_proxy$/, '').gsub('_', '-')
end

#observation_request_to_event_mapping ⇒ Object

Subclasses must override with their own mappings



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# File 'lib/glimmer/swt/widget_proxy.rb', line 267

def observation_request_to_event_mapping
  {}
end

#observation_requests ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 370

def observation_requests
  @observation_requests ||= {}
end

#parent_dom_element ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 214

def parent_dom_element
  Document.find(parent_path)
end

#parent_path ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 210

def parent_path
  @parent.path
end

#post_add_content ⇒ Object

Executes at the closing of a parent widget curly braces after all children/properties have been added/set



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# File 'lib/glimmer/swt/widget_proxy.rb', line 126

def post_add_content
  # No Op by default
end

#post_dispose_child(child) ⇒ Object

Executes for the parent of a child that just got disposed



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# File 'lib/glimmer/swt/widget_proxy.rb', line 121

def post_dispose_child(child)
  @children&.delete(child)
end

#post_initialize_child(child) ⇒ Object

Executes for the parent of a child that just got added



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# File 'lib/glimmer/swt/widget_proxy.rb', line 115

def post_initialize_child(child)
  @children << child
  child.render
end

#property_type_converters ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 431

def property_type_converters
  color_converter = lambda do |value|
    if value.is_a?(Symbol) || value.is_a?(String)
      ColorProxy.new(value)
    else
      value
    end
  end
  @property_type_converters ||= {
    :background => color_converter,
#           :background_image => lambda do |value|
#             if value.is_a?(String)
#               if value.start_with?('uri:classloader')
#                 value = value.sub(/^uri\:classloader\:\//, '')
#                 object = java.lang.Object.new
#                 value = object.java_class.resource_as_stream(value)
#                 value = java.io.BufferedInputStream.new(value)
#               end
#               image_data = ImageData.new(value)
#               on_event_Resize do |resize_event|
#                 new_image_data = image_data.scaledTo(@swt_widget.getSize.x, @swt_widget.getSize.y)
#                 @swt_widget.getBackgroundImage&.dispose
#                 @swt_widget.setBackgroundImage(Image.new(@swt_widget.getDisplay, new_image_data))
#               end
#               Image.new(@swt_widget.getDisplay, image_data)
#             else
#               value
#             end
#           end,
    :foreground => color_converter,
#           :font => lambda do |value|
#             if value.is_a?(Hash)
#               font_properties = value
#               FontProxy.new(self, font_properties).swt_font
#             else
#               value
#             end
#           end,
    :text => lambda do |value|
#             if swt_widget.is_a?(Browser)
#               value.to_s
#             else
        value.to_s
#             end
    end,
#           :visible => lambda do |value|
#             !!value
#           end,
  }
end

#remove_all_listeners ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 154

def remove_all_listeners
  effective_observation_request_to_event_mapping.keys.each do |keyword|
    effective_observation_request_to_event_mapping[keyword].to_collection.each do |mapping|
      observation_requests[keyword].to_a.each do |event_listener|
        event = mapping[:event]
        event_handler = mapping[:event_handler]
        event_element_css_selector = mapping[:event_element_css_selector]
        the_listener_dom_element = event_element_css_selector ? Element[event_element_css_selector] : listener_dom_element
        the_listener_dom_element.off(event)
      end
    end
  end
end

#remove_css_class(css_class) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 312

def remove_css_class(css_class)
  dom_element.remove_class(css_class)
end

#remove_css_classes(css_classes_to_remove) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 316

def remove_css_classes(css_classes_to_remove)
  css_classes_to_remove.each {|css_class| remove_css_class(css_class)}
end

#render(custom_parent_dom_element = nil) ⇒ Object Also known as: redraw 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 218

def render(custom_parent_dom_element = nil)
  the_parent_dom_element = custom_parent_dom_element || parent_dom_element
  old_element = dom_element
  brand_new = @dom.nil? || old_element.empty?
  build_dom(!custom_parent_dom_element) # TODO handle custom parent layout by passing parent instead of parent dom element
  if brand_new
    the_parent_dom_element.append(@dom)
  else
    old_element.replace_with(@dom)
  end
  observation_requests&.clone&.each do |keyword, event_listener_set|
    event_listener_set.each do |event_listener|
      observation_requests[keyword].delete(event_listener) # TODO look into the implications of this and if it's needed.
      handle_observation_request(keyword, &event_listener)
    end
  end
  children.each do |child|
    child.render
  end
  @rendered = true
  content_on_render_blocks.each { |content_block| content(&content_block) }
end

#selector ⇒ Object

Subclasses can override with their own selector



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# File 'lib/glimmer/swt/widget_proxy.rb', line 300

def selector
  "#{name}##{id}"
end

#set_attribute(attribute_name, *args) ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 406

def set_attribute(attribute_name, *args)
  apply_property_type_converters(attribute_name, args)
  super(attribute_name, *args) # PropertyOwner
end

#set_data(key = nil, value) ⇒ Object Also known as: setData, data= 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 130

def set_data(key=nil, value)
  @data[key] = value
end

#set_focus ⇒ Object Also known as: setFocus 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 205

def set_focus
  self.focus = true
end

#style_element ⇒ Object

TODO consider adding a default #dom method implementation for the common case, automatically relying on #element and other methods to build the dom html



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# File 'lib/glimmer/swt/widget_proxy.rb', line 335

def style_element
  style_element_id = "#{id}-style"
  style_element_selector = "style##{style_element_id}"
  element = dom_element.find(style_element_selector)
  if element.empty?
    new_element = Element.new(:style)
    new_element.attr('id', style_element_id)
    new_element.attr('class', "#{name.gsub('_', '-')}-instance-style widget-instance-style")
    dom_element.prepend(new_element)
    element = dom_element.find(style_element_selector)
  end
  element
end

#widget_property_listener_installers ⇒ Object 



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# File 'lib/glimmer/swt/widget_proxy.rb', line 482

def widget_property_listener_installers
  @swt_widget_property_listener_installers ||= {
#           WidgetProxy => {
#             :focus => lambda do |observer|
#               on_focus_gained { |focus_event|
#                 observer.call(true)
#               }
#               on_focus_lost { |focus_event|
#                 observer.call(false)
#               }
#             end,
#           },
    TextProxy => {
      :text => lambda do |observer|
        on_modify_text { |modify_event|
          observer.call(text)
        }
      end,
#             :caret_position => lambda do |observer|
#               on_event_keydown { |event|
#                 observer.call(getCaretPosition)
#               }
#               on_event_keyup { |event|
#                 observer.call(getCaretPosition)
#               }
#               on_event_mousedown { |event|
#                 observer.call(getCaretPosition)
#               }
#               on_event_mouseup { |event|
#                 observer.call(getCaretPosition)
#               }
#             end,
#             :selection => lambda do |observer|
#               on_event_keydown { |event|
#                 observer.call(getSelection)
#               }
#               on_event_keyup { |event|
#                 observer.call(getSelection)
#               }
#               on_event_mousedown { |event|
#                 observer.call(getSelection)
#               }
#               on_event_mouseup { |event|
#                 observer.call(getSelection)
#               }
#             end,
#             :selection_count => lambda do |observer|
#               on_event_keydown { |event|
#                 observer.call(getSelectionCount)
#               }
#               on_event_keyup { |event|
#                 observer.call(getSelectionCount)
#               }
#               on_event_mousedown { |event|
#                 observer.call(getSelectionCount)
#               }
#               on_event_mouseup { |event|
#                 observer.call(getSelectionCount)
#               }
#             end,
#             :top_index => lambda do |observer|
#               @last_top_index = getTopIndex
#               on_paint_control { |event|
#                 if getTopIndex != @last_top_index
#                   @last_top_index = getTopIndex
#                   observer.call(@last_top_index)
#                 end
#               }
#             end,
    },
#           Java::OrgEclipseSwtCustom::StyledText => {
#             :text => lambda do |observer|
#               on_modify_text { |modify_event|
#                 observer.call(getText)
#               }
#             end,
#           },
    DateTimeProxy => {
      :date_time => lambda do |observer|
        on_widget_selected { |selection_event|
          observer.call(date_time)
        }
      end
    },
    RadioProxy => { #radio?
      :selection => lambda do |observer|
        on_widget_selected { |selection_event|
          observer.call(selection)
        }
      end
    },
    TableProxy => {
      :selection => lambda do |observer|
        on_widget_selected { |selection_event|
          observer.call(selection_event.table_item.get_data)  # TODO ensure selection doesn't conflict with editing
        }
      end,
    },
#           Java::OrgEclipseSwtWidgets::MenuItem => {
#             :selection => lambda do |observer|
#               on_widget_selected { |selection_event|
#                 observer.call(getSelection)
#               }
#             end
#           },
#           Java::OrgEclipseSwtWidgets::Spinner => {
#             :selection => lambda do |observer|
#               on_widget_selected { |selection_event|
#                 observer.call(getSelection)
#               }
#             end
#           },
  }
end