Module: Glimmer::LibUI::DataBindable

Included in:
AttributedString, ControlProxy, Shape
Defined in:
lib/glimmer/libui/data_bindable.rb

Overview

Parent controls and shapes who have children and add child post_initialize_child

Instance Method Summary collapse

Instance Method Details

#data_bind(property, model_binding) ⇒ Object

Sets up read/write (bidirectional) data-binding

classes are expected to implement ‘data_bind_write(property, model_binding)` to setup write data-binding by observing view property for changes and writing to model attribute via model binding accordingly

classes can override data_bind_read to disable read data-binding in rare scenarios that might need it

returns model attribute reading observer registration by default



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# File 'lib/glimmer/libui/data_bindable.rb', line 34

def data_bind(property, model_binding)
  data_bind_read(property, model_binding).tap do
    data_bind_write(property, model_binding) unless model_binding.binding_options[:read_only]
  end
end

#data_bind_read(property, model_binding) ⇒ Object

Sets up read data-binding (reading from model to update view)

Default implementation observes model attribute for changes via model binding and updates view property accordingly



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# File 'lib/glimmer/libui/data_bindable.rb', line 44

def data_bind_read(property, model_binding)
  model_attribute_observer = Glimmer::DataBinding::Observer.proc do
    new_value = model_binding.evaluate_property # TODO performance might be worse for not using block value instead (double double call on evaluate_property)
    send("#{property}=", new_value) unless send(property) == new_value
  end
  observer_registration = model_attribute_observer.observe(model_binding, attribute_writer_type: [:attribute=, :set_attribute])
  model_attribute_observer.call # initial update
  data_binding_model_attribute_observer_registrations << observer_registration
  observer_registration
end

#data_bind_write(property, model_binding) ⇒ Object

Sets up write data-binding (writing to model from view)

Has no implementation by default. Classes are expected to implement this method by observing view property for changes and writing them to model accordingly via model binding



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# File 'lib/glimmer/libui/data_bindable.rb', line 60

def data_bind_write(property, model_binding)
  # No Op by default
end

#data_binding_model_attribute_observer_registrations ⇒ Object 



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# File 'lib/glimmer/libui/data_bindable.rb', line 64

def data_binding_model_attribute_observer_registrations
  @data_binding_model_attribute_observer_registrations ||= []
end