Class: React::RenderingContext

Inherits:
Object
  • Object
show all
Defined in:
lib/react/rendering_context.rb

Class Attribute Summary collapse

Class Method Summary collapse

Class Attribute Details

.waiting_on_resources ⇒ Object

Returns the value of attribute waiting_on_resources.



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# File 'lib/react/rendering_context.rb', line 4

def waiting_on_resources
  @waiting_on_resources
end

Class Method Details

.as_node(element) ⇒ Object Also known as: delete 



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# File 'lib/react/rendering_context.rb', line 51

def as_node(element)
  @buffer.delete(element)
  element
end

.build ⇒ Object 



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# File 'lib/react/rendering_context.rb', line 43

def build
  current = @buffer
  @buffer = []
  return_val = yield @buffer
  @buffer = current
  return_val
end

.build_only(name, *args, &block) ⇒ Object 



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# File 'lib/react/rendering_context.rb', line 6

def build_only(name, *args, &block)
  React::Component.deprecation_warning(
    '..._as_node is deprecated.  Render component and then use the .node method instead'
  )
  React::RenderingContext.build { React::RenderingContext.render(name, *args, &block) }.to_n
end

.improper_render(message, solution) ⇒ Object 



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# File 'lib/react/rendering_context.rb', line 112

def improper_render(message, solution)
  raise "a component's render method must generate and return exactly 1 element or a string.\n"\
        "    #{message}  #{solution}"
end

.raise_render_error(result) ⇒ Object

heurestically raise a meaningful error based on the situation



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# File 'lib/react/rendering_context.rb', line 101

def raise_render_error(result)
  improper_render 'A different element was returned than was generated within the DSL.',
                  'Possibly improper use of Element#delete.' if @buffer.count == 1
  improper_render "Instead #{@buffer.count} elements were generated.",
                  'Do you want to wrap your elements in a div?' if @buffer.count > 1
  improper_render "Instead the component #{result} was returned.",
                  "Did you mean #{result}()?" if result.try :reactrb_component?
  improper_render "Instead the #{result.class} #{result} was returned.",
                  'You may need to convert this to a string.'
end

.remove_nodes_from_args(args) ⇒ Object 



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# File 'lib/react/rendering_context.rb', line 66

def remove_nodes_from_args(args)
  args[0].each do |key, value|
    value.as_node if value.is_a?(Element) rescue nil
  end if args[0] && args[0].is_a?(Hash)
end

.render(name, *args, &block) ⇒ Object 



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# File 'lib/react/rendering_context.rb', line 13

def render(name, *args, &block)
  remove_nodes_from_args(args)
  @buffer ||= [] unless @buffer
  if block
    element = build do
      saved_waiting_on_resources = waiting_on_resources
      self.waiting_on_resources = nil
      run_child_block(name.nil?, &block)
      if name
        buffer = @buffer.dup
        React.create_element(name, *args) { buffer }.tap do |element|
          element.waiting_on_resources = saved_waiting_on_resources || !!buffer.detect { |e| e.waiting_on_resources if e.respond_to?(:waiting_on_resources) }
        end
      elsif @buffer.last.is_a? React::Element
        @buffer.last.tap { |element| element.waiting_on_resources ||= saved_waiting_on_resources }
      else
        @buffer.last.to_s.span.tap { |element| element.waiting_on_resources = saved_waiting_on_resources }
      end
    end
  elsif name.is_a? React::Element
    element = name
  else
    element = React.create_element(name, *args)
    element.waiting_on_resources = waiting_on_resources
  end
  @buffer << element
  self.waiting_on_resources = nil
  element
end

.rendered?(element) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/react/rendering_context.rb', line 58

def rendered?(element)
  @buffer.include? element
end

.replace(e1, e2) ⇒ Object 



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# File 'lib/react/rendering_context.rb', line 62

def replace(e1, e2)
  @buffer[@buffer.index(e1)] = e2
end

.run_child_block(is_outer_scope) ⇒ Object

run_child_block gathers the element(s) generated by a child block. for example when rendering this div: div { “hello”.span; “goodby”.span } two child Elements will be generated.

the final value of the block should either be

1 an object that responds to :acts_as_string?
2 a string,
3 an element that is NOT yet pushed on the rendering buffer
4 or the last element pushed on the buffer

in case 1 we change the object to a string, and then it becomes case 2 in case 2 we automatically push the string onto the buffer in case 3 we also push the Element onto the buffer IF the buffer is empty case 4 requires no special processing

Once we have taken care of these special cases we do a check IF we are in an outer rendering scope. In this case react only allows us to generate 1 Element so we insure that is the case, and also check to make sure that element in the buffer is the element returned



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# File 'lib/react/rendering_context.rb', line 92

def run_child_block(is_outer_scope)
  result = yield
  result = result.to_s if result.try :acts_as_string?
  @buffer << result if result.is_a?(String) || (result.is_a?(Element) && @buffer.empty?)
  raise_render_error(result) if is_outer_scope && @buffer != [result]
end