Class: Rfm::Metadata::Field

Inherits:
Object show all
Defined in:
lib/rfm/metadata/field.rb

Overview

The Field object represents a single FileMaker field. It *does not hold the data* in the field. Instead, it serves as a source of metadata about the field. For example, if your script is trying to be highly dynamic about its field access, it may need to determine the data type of a field at run time. Here’s how:

field_name = "Some Field Name"
case myRecord.fields[field_name].result
when "text"
  # it is a text field, so handle appropriately
when "number"
  # it is a number field, so handle appropriately
end

Attributes

The Field object has the following attributes:

  • name is the name of the field

  • result is the data type of the field; possible values include:

    • text

    • number

    • date

    • time

    • timestamp

    • container

  • type any of these:

    • normal (a normal data field)

    • calculation

    • summary

  • max_repeats is the number of repetitions (1 for a normal field, more for a repeating field)

  • global is true is this is a global field, false otherwise

Note: Field types match FileMaker’s own values, but the terminology differs. The result attribute tells you the data type of the field, regardless of whether it is a calculation, summary, or normal field. So a calculation field whose result type is timestamp would have these attributes:

  • result: timestamp

  • type: calculation

  • *control& is a FieldControl object representing the sytle and value list information associated with this field on the layout.

Note: Since a field can sometimes appear on a layout more than once, control may be an Array. If you don’t know ahead of time, you’ll need to deal with this. One easy way is:

controls = [myField.control].flatten
controls.each {|control|
  # do something with the control here
}

The code above makes sure the control is always an array. Typically, though, you’ll know up front if the control is an array or not, and you can code accordingly.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(attributes) ⇒ Field

Initializes a field object. You’ll never need to do this. Instead, get your Field objects from Resultset::field_meta



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# File 'lib/rfm/metadata/field.rb', line 69

def initialize(attributes)
	if attributes && attributes.size > 0
		_attach_as_instance_variables attributes
	end
	self
end

Instance Attribute Details

#global ⇒ Object (readonly)

Returns the value of attribute global.



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# File 'lib/rfm/metadata/field.rb', line 64

def global
  @global
end

#max_repeats ⇒ Object (readonly)

Returns the value of attribute max_repeats.



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# File 'lib/rfm/metadata/field.rb', line 64

def max_repeats
  @max_repeats
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/rfm/metadata/field.rb', line 64

def name
  @name
end

#result ⇒ Object (readonly)

Returns the value of attribute result.



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# File 'lib/rfm/metadata/field.rb', line 64

def result
  @result
end

#type ⇒ Object (readonly)

Returns the value of attribute type.



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# File 'lib/rfm/metadata/field.rb', line 64

def type
  @type
end

Instance Method Details

#coerce(value) ⇒ Object

Coerces the text value from an fmresultset document into proper Ruby types based on the type of the field. You’ll never need to do this: Rfm does it automatically for you when you access field data through the Record object.



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# File 'lib/rfm/metadata/field.rb', line 79

def coerce(value)
  case
  when (value.nil? or value.empty?); return nil
  when value.is_a?(Array); return value.collect {|v| coerce(v)}
  when value.is_a?(Hash); return coerce(value.values[0])
  end
  
  case result
  when "text"      then value
  when "number"    then BigDecimal.new(value.to_s)
  when "date"      then Date.strptime(value, resultset_meta.date_format)
  when "time"      then DateTime.strptime("1/1/-4712 #{value}", "%m/%d/%Y #{resultset_meta.time_format}")
  when "timestamp" then DateTime.strptime(value, resultset_meta.timestamp_format)
  when "container" then
  	#resultset_meta = resultset.instance_variable_get(:@meta)
  	if resultset_meta && resultset_meta['doctype'] && value.to_s[/\?/]
  		URI.parse(resultset_meta['doctype'].last.to_s).tap{|uri| uri.path, uri.query = value.split('?')}
  	else
  		value
  	end
  else nil
  end
rescue
  puts("ERROR in Field#coerce:", name, value, result, resultset_meta.timestamp_format, $!)
  nil
end

#field_definition_element_close_callback(cursor) ⇒ Object 



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# File 'lib/rfm/metadata/field.rb', line 111

def field_definition_element_close_callback(cursor)
	#self.resultset = cursor.top.object
	#resultset_meta = resultset.instance_variable_get(:@meta)
	self.resultset_meta = cursor.top.object.instance_variable_get(:@meta)
	#puts ["\nFIELD#field_definition_element_close_callback", resultset_meta]
	resultset_meta.field_meta[get_mapped_name.to_s.downcase] = self
end

#get_mapped_name ⇒ Object 



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# File 'lib/rfm/metadata/field.rb', line 106

def get_mapped_name
	#(resultset_meta && resultset_meta.layout && resultset_meta.layout.field_mapping[name]) || name
	layout_object.field_mapping[name] || name
end

#relatedset_field_definition_element_close_callback(cursor) ⇒ Object 



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# File 'lib/rfm/metadata/field.rb', line 119

def relatedset_field_definition_element_close_callback(cursor)
	#self.resultset = cursor.top.object
	self.resultset_meta = cursor.top.object.instance_variable_get(:@meta)
	cursor.parent.object[get_mapped_name.split('::').last.to_s.downcase] = self
	#puts ['FIELD_portal_callback', name, cursor.parent.object.object_id, cursor.parent.tag, cursor.parent.object[name.split('::').last.to_s.downcase]].join(', ')
end