Class: Canis::DefaultTableRowSorter

Inherits:
Object
  • Object
show all
Defined in:
lib/canis/core/widgets/table.rb

Overview

This is our default table row sorter. It does a multiple sort and allows for reverse sort also. It’s a pretty simple sorter and uses sort, not sort_by. Improvements welcome. Usage: provide model in constructor or using model method Call toggle_sort_order(column_index) Call sort. Currently, this sorts the provided model in-place. Future versions may maintain a copy, or use a table that provides a mapping of model to result. # TODO check if column_sortable

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(data_model = nil) ⇒ DefaultTableRowSorter

model is array of data



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# File 'lib/canis/core/widgets/table.rb', line 94

def initialize data_model=nil
  self.model = data_model
  @columns_sort = []
  @sort_keys = nil
end

Instance Attribute Details

#sort_keys ⇒ Object (readonly)

Returns the value of attribute sort_keys.



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# File 'lib/canis/core/widgets/table.rb', line 92

def sort_keys
  @sort_keys
end

Instance Method Details

#model=(model) ⇒ Object 



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# File 'lib/canis/core/widgets/table.rb', line 99

def model=(model)
  @model = model
  @sort_keys = nil
end

#set_sort_keys(list) ⇒ Object 



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# File 'lib/canis/core/widgets/table.rb', line 187

def set_sort_keys list
  @sort_keys = list
end

#sort ⇒ Object

sorts the model based on sort keys and reverse flags



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# File 'lib/canis/core/widgets/table.rb', line 117

def sort
  return unless @model
  return if @sort_keys.empty?
  $log.debug "TABULAR SORT KEYS #{sort_keys} "
  # first row is the header which should remain in place
  # We could have kept column headers separate, but then too much of mucking around
  # with textpad, this way we avoid touching it
  header = @model.delete_at 0
  begin
    # next line often can give error "array within array" - i think on date fields that 
    #  contain nils
  @model.sort!{|x,y| 
    res = 0
    @sort_keys.each { |ee| 
      e = ee.abs-1 # since we had offsetted by 1 earlier
      abse = e.abs
      if ee < 0
        xx = x[abse]
        yy = y[abse]
        # the following checks are since nil values cause an error to be raised
        if xx.nil? && yy.nil?
          res = 0
        elsif xx.nil?
          res = 1
        elsif yy.nil?
          res = -1
        else
        res = y[abse] <=> x[abse]
        end
      else
        xx = x[e]
        yy = y[e]
        # the following checks are since nil values cause an error to be raised
        # whereas we want a nil to be wither treated as a zero or a blank
        if xx.nil? && yy.nil?
          res = 0
        elsif xx.nil?
          res = -1
        elsif yy.nil?
          res = 1
        else
        res = x[e] <=> y[e]
        end
      end
      break if res != 0
    }
    res
  }
  ensure
    @model.insert 0, header if header
  end
end

#sortable(colindex, tf) ⇒ Object 



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# File 'lib/canis/core/widgets/table.rb', line 103

def sortable colindex, tf
  @columns_sort[colindex] = tf
end

#sortable?(colindex) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/canis/core/widgets/table.rb', line 106

def sortable? colindex
  return false if @columns_sort[colindex]==false
  return true
end

#toggle_sort_order(index) ⇒ Object

toggle the sort order if given column offset is primary sort key Otherwise, insert as primary sort key, ascending.



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# File 'lib/canis/core/widgets/table.rb', line 171

def toggle_sort_order index
  index += 1 # increase by 1, since 0 won't multiple by -1
  # internally, reverse sort is maintained by multiplying number by -1
  @sort_keys ||= []
  if @sort_keys.first && index == @sort_keys.first.abs
    @sort_keys[0] *= -1 
  else
    @sort_keys.delete index # in case its already there
    @sort_keys.delete(index*-1) # in case its already there
    @sort_keys.unshift index
    # don't let it go on increasing
    if @sort_keys.size > 3
      @sort_keys.pop
    end
  end
end

#use_to_s(colindex) ⇒ Object

should to_s be used for this column



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# File 'lib/canis/core/widgets/table.rb', line 111

def use_to_s colindex
  return true # TODO
end