Class: ObjectTableModel

Inherits:
Qt::AbstractTableModel
  • Object
show all
Includes:
Enumerable, QtFlags
Defined in:
lib/qtext/object_table_model.rb

Overview

A specialisation of Qt::TableModel that is given a collection of objects, and a collection of headers, which are methods to call on the objects to populate columns.

Given

Thing = Struct.new( :name, :value, :location, :price, :other, :ignored )

and

@data = method_to_create_lots_of_things

The following will display the four named attributes in 4 columns

ObjectTableModel.new :data => @data, :headers => [ :name, :value, :location, :price ]

and this will right-align the price column:

ObjectTableModel.new :data => @data, :headers => [ :name, :value, :location, Header.new( :attribute => :price, :alignment => Qt::AlignRight ) ]

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from QtFlags

#const_as_string, #item_boolean_flags, #qt_aligncenter, #qt_alignleft, #qt_alignright, #qt_background_role, #qt_checked, #qt_checkstate_role, #qt_decoration_role, #qt_display_role, #qt_edit_role, #qt_font_role, #qt_foreground_role, #qt_item_is_editable, #qt_paste_role, #qt_size_hint_role, #qt_text_alignment_role, #qt_tooltip_role, #qt_unchecked

Constructor Details

#initialize(args = {}) ⇒ ObjectTableModel

args can contain the following:

  • :parent => the Qt::Object that is the parent of this class.

  • :headers => array of either symbols representing the attribute on the elements of the data collection, or Header instances.

  • :data => array of objects, with attributes corresponding to the headers

  • :collection is an alias for :data



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# File 'lib/qtext/object_table_model.rb', line 81

def initialize( args = {} )
  super( args[:parent] )
  @parent = args[:parent]
  @collection = args[:data] || args[:collection] || []
  set_headers( args[:headers] )
end

Instance Attribute Details

#collection ⇒ Object

Returns the value of attribute collection.



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# File 'lib/qtext/object_table_model.rb', line 63

def collection
  @collection
end

#headers ⇒ Object

Returns the value of attribute headers.



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# File 'lib/qtext/object_table_model.rb', line 63

def headers
  @headers
end

Instance Method Details

#<<(obj) ⇒ Object

Insert a new object into the collection, and make sure the view is updated.



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# File 'lib/qtext/object_table_model.rb', line 238

def <<( obj )
  beginInsertRows( Qt::ModelIndex.invalid, collection.size, collection.size )
  collection << obj
  endInsertRows
end

#[](index) ⇒ Object 



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# File 'lib/qtext/object_table_model.rb', line 221

def []( index )
  collection[index]
end

#[]=(index, value) ⇒ Object

Set the value at the index, and make sure the view is updated.



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# File 'lib/qtext/object_table_model.rb', line 226

def []=( index, value )
  if index >= collection.size
    beginInsertRows( Qt::ModelIndex.invalid, collection.size, collection.size + ( index - collection.size ) )
    collection[index] = value
    endInsertRows
  else
    collection[index] = value
    emit dataChanged( create_index( index.row, 0 ), create_index( index.row, columnCount ) )
  end
end

#clear ⇒ Object 



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# File 'lib/qtext/object_table_model.rb', line 253

def clear
  collection.clear
  reset
end

#column_count(parent_index = Qt::ModelIndex.invalid) ⇒ Object

Rubyish method for columnCount



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# File 'lib/qtext/object_table_model.rb', line 71

def column_count( parent_index = Qt::ModelIndex.invalid )
  columnCount( parent_index )
end

#columnCount(parent_model_index = Qt::ModelIndex.invalid) ⇒ Object 



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# File 'lib/qtext/object_table_model.rb', line 97

def columnCount( parent_model_index = Qt::ModelIndex.invalid )
  if parent_model_index.valid?
    parent_model_index.entity.children.size == 0 ? 0 : headers.size
  else
    headers.size
  end
end

#data(index, role = qt_display_role) ⇒ Object

implementation of Qt:AbstractItemModel method



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# File 'lib/qtext/object_table_model.rb', line 146

def data( index, role = qt_display_role )
  return nil.to_variant unless index.valid?
  #~ puts "requesting data for index: #{index.inspect} and role: #{const_as_string role}"
  begin
    retval =
    case role
      when qt_display_role, qt_edit_role
        field_value_at( index )
       
      when qt_text_alignment_role
        headers[index.column].alignment
        
      when qt_checkstate_role
        #~ value = self[index.row].send( attribute_for_index( index.column ) )
        #~ value ? Qt::Checked : Qt::Unchecked
        
      # these are just here to make debug output quieter
      when qt_size_hint_role;
      when qt_background_role;
      when qt_font_role;
      when qt_foreground_role;
      when qt_decoration_role;
      
      when qt_tooltip_role;
        
      else
        puts "data index: #{index}, role: #{const_as_string(role)}" if $OPTIONS[:debug]
        nil
    end
      
    # return a variant
    retval.to_variant
  rescue Exception => e
    puts e.backtrace.join( "\n" )
    puts "#{index.inspect} #{e.message}"
    nil.to_variant
  end
end

#each(&block) ⇒ Object 



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# File 'lib/qtext/object_table_model.rb', line 245

def each( &block )
  collection.each( &block )
end

#flags(index) ⇒ Object

implementation of Qt:AbstractItemModel method – TODO make this editable



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# File 'lib/qtext/object_table_model.rb', line 216

def flags( index )
  return 0 unless index.valid?
  super
end

#headerData(section, orientation, role) ⇒ Object

implementation of Qt:AbstractItemModel method



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# File 'lib/qtext/object_table_model.rb', line 119

def headerData( section, orientation, role )
  value =
  case orientation 
    when Qt::Vertical
      case role
        when qt_display_role
          ( section + 1 ).to_s
        
        when qt_text_alignment_role
          Qt::AlignVCenter | Qt::AlignRight
        
      end
    
    when Qt::Horizontal
      case role
        when qt_display_role
          headers[section].title
        
        when qt_text_alignment_role
          Qt::AlignVCenter | Qt::AlignCenter
        
      end
  end
  value.to_variant
end

#parent(*args) ⇒ Object

TODO what exactly is this for again? Something to do with QWidget.parent() and Qt::AbstractTableModel.parent(…)



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# File 'lib/qtext/object_table_model.rb', line 107

def parent( *args )
  if args.size == 0
    retval = super()
    retval || @parent
  else
    if model_index.valid?
      collection.index( model_index.entity.parent )
    end
  end
end

#row_count(parent_index = Qt::ModelIndex.invalid) ⇒ Object

Rubyish method for rowCount



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# File 'lib/qtext/object_table_model.rb', line 66

def row_count( parent_index = Qt::ModelIndex.invalid )
  rowCount( parent_index )
end

#rowCount(parent_model_index = Qt::ModelIndex.invalid) ⇒ Object

implementation of Qt:AbstractItemModel method



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# File 'lib/qtext/object_table_model.rb', line 89

def rowCount( parent_model_index = Qt::ModelIndex.invalid )
  if parent_model_index.valid?
    parent_model_index.entity.children.size
  else
    collection.size
  end
end

#setData(index, variant, role = qt_edit_role) ⇒ Object

implementation of Qt:AbstractItemModel method



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# File 'lib/qtext/object_table_model.rb', line 186

def setData( index, variant, role = qt_edit_role )
  return false unless index.valid?
  begin
    item = self[index.row]
    method_name = attribute_for_index( index.column ).to_s
    value =
    case role
      when qt_edit_role
        variant.value
      when qt_checkstate_role
        case variant.value
          when Qt::Checked; true
          when Qt::Unchecked; false
          else; false
        end
    end
    
    # update UI
    emit dataChanged( index, index )
    
    # value conversion OK
    true
  rescue Exception => e
    puts e.message
    false
  end
end

#to_a ⇒ Object 



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# File 'lib/qtext/object_table_model.rb', line 249

def to_a
  collection.dup
end